Pause (?)

by Judith Curry

Question of the week:

Has the rate of warming continued unabated, or has there been a  pause in the warming?

Actually, four different questions seem to be floating around in terms of the BEST media coverage:

  1. Has the earth been warming? Addressing this question in a sensible way requires that a specific period be specified, presumably in the context of the increase in atmospheric CO2 concentrations.
  2. Is global warming over?  Addressing this question requires a prediction of future temperatures, and we can’t really answer that with the data.
  3. Has global warming stopped?  Addressing this questions requires clarifying whether it is only the actual global temperature under discussion, or whether it is the attribution to humans that has stopped (i.e. beyond the expected range of natural variability)?
  4. Has there been a pause in the global warming?  Addressing this question requires a clarification of of the specific period of interest, and whether the “pause” indicates zero temperature change, or a rate of warming that is less than the expected temperature change.

What does the BEST land temperature data have to say about global warming?  Not much, since the BEST data only covers the land (~30% of the global area).  The BEST land data should not be used to infer anything quantitative about GLOBAL warming.

IMO, the significance of the BEST data in terms of the temperature record of the past 50 years or so is that it puts to rest the concern that Phil Jones and Jim Hansen have “cooked” the land surface temperature data.  This has not been a serious concern among the people paying close attention to this issue and who actually read the journal publications and look at the actual data; but it is a concern in certain circles, and in the U.S. this concern has been raised by at least one Republican presidential candidate.  The relatively small discrepancies between the BEST and the GISS and CRU data sets are of some interest; the apparent discrepancy with GISS has been resolved.  Note:  the CRU data set shows less warming than BEST over the past 15 years.

Back to the 4 questions, which require consideration of the GLOBAL surface temperature data.  In terms of simple yes or no answers,  there may be different answers to each of these 4 questions.  Addressing each of these questions in a sensible way requires analyzing different periods of the data record.  But most importantly, they require analysis of the global data, particularly the ocean data.

Further, addressing these questions requires an unambiguous definition of ‘warming’, ‘stopped’, and ‘paused’.  ‘Warming’  means a rate of change of temperature that is greater than zero.  Here I  define “stopped” to mean a rate of change of temperature that is less than or equal to zero.  Here I define “pause” to mean a rate of increase of temperature that is less than 0.17 – 0.2 C/decade.  Why 0.17 -0.2 C/decade as a threshold?  From the IPCC AR4 re global temperature trends:

  • Observed temperature trends (C/decade) for the period 1979-2004:   CRU 0.163;  NCDC 0.174;  GISS 0.170  (Chapter 3)
  • Observed temperature trend (C/decade) 1981-2005:  0.177 (FAQ 3.1)
  • “For the next two decades, a warming of about 0.2°C per decade is projected for a range of SRES emission scenarios.”  (Summary for Policy Makers)

So what is the evidence for suggesting a ‘pause’ or even a ‘stop’ during the past decade or so?

  • HadCRUT3 global temperatures (1998-2010) [link]
  • 0-700 m global ocean heat content (2002-present) [link]
  • ERSSTv2 global sea surface temperatures (1998-2010) [link]

Note: for reference, the global ocean SST temperature trend (C per decade) for 1979-2005 was reported by the IPCC to be 0.134.

A key issue in identifying and interpreting the pause is the start date chosen to evaluate a pause.  If one is seeking to identify an anthropogenic signal, one should choose years at each end point that are neutral in terms of ENSO and also the 9.1 year AMO signal discussed by Muller et al.   For a short temperature record (i.e. of relevance to assessing whether there has been a pause over the past decade), this isn’t feasible.  In any event, identifying an AGW signal on this short timescale isn’t useful.  What is of interest on this timescale is whether natural variability (forced and unforced) can dominate the AGW signal on decadal timescales and produce a ‘pause’ or a ‘stop’.  This is the issue addressed by Santer et al., searching for the AGW signal amidst the natural variability noise.  Santer et al. argue that “Our results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature.”

So in this context, starting the analysis in 1998 is not unreasonable.  I have also become intrigued by the varying magnitudes of the 1998 anomaly spike among the different datasets.  Among the GISS, HADCRUT, BEST, NCDC, ERSST, and NODC datasets, it is only HADCRUT that has a large 1998 spike.  The magnitude of the spike is larger over land than ocean, and also largest in the Southern Hemisphere.  Understanding the large discrepancy in the 1998 anomaly among the different datasets (also land/ocean and regional)  seems to me like an important thing to pursue.

Another rationale for a starting point is the analysis of Tsonis, who argues for a climate shift ca. 2001/2002, based upon synchronized chaos in the context of the major ocean oscillations.  This latest climate shift is characterized by increased frequency of La Nina events and a break in the global mean temperature trend.

This concept of a recent pause in the warming seems to be fairly widely accepted by many mainstream consensus scientists (e.g. the recent Greenwire article),with explanations ranging from aerosols, to solar, to oceans. The duration and magnitude of a pause that is significant in the context of the AGW debate is debatable, but I have made some suggestions.  Note that the short time scales considered here preclude determination of a statistically significant trend at the 95% confidence level, although lack of statistical signficance does not negate the existence of a pause as defined here.

This issue of ‘pause’ has generated a plethora of blogoshperic analyses of the recent record  in the Berkeley Earth and other data sets (much traffic for woodfortrees).  Statistical analyses of various data sets over various periods aren’t all that interesting in the absence of an hypothesis that is related to a physical mechanism.  I hope that this post stimulates more meaningful analyses of the recent data record.

801 responses to “Pause (?)

  1. Or plateaued–>

    • Roy Spenser’s UAH global temperature anomaly starts of with a 17-year pause. Look at the UAH OLS line for 1979-95 in the linked chart. It’s flat as pancake. So pauses in rising global temperature aren’t anything new.

      http://www.woodfortrees.org/plot/uah/from:1979/to:1995/plot/uah/from:1979/to:1995/trend

      • Hence by Santer’s rule there is no AGW signal whatsoever. Moreover, this is precisely the time period when the surface statistical models show the spurt of warming that is supposed to be the evidence for AGW. That is, the surface models show no warming for the preceding 30 to 40 years, just during this period.

        In any normal science this protracted lack of atmospheric warming would be sufficient to falsify AGW, but not in climate science. That it does not may be a measure of how politicized climate science has become.

        On the other hand, the Copernican, sun-centered system was not adopted for 100 years or so. Scientists can be stubborn.

      • Really you think that piece of data tells us that rising CO2 levels aren’t having a warming effect on the planet? pull the other one

      • lolwat: That is just what it tells me. What does it tell you?

      • Vince whirlwind

        It’s not telling him that, what it’s doing is confirming his bias. For the unbiased, there is clearly no “protracted lack of warming”.

      • There’s a very nice irony here. For the true believers in CAGW this last decade of no warming has been agonizingly protracted, but they have to pretend it isn’t very long at all.
        ================

      • Vince whirlwind

        Kim, as any competent statistician will tell you, ten years is not long enough for statistical significance. The statistically significant trend, right now, is upward. Whatever it is you are telling yourself is appearing in the last ten-years’ record is simply not there.

      • Politicized science and exponentially improving abilities to compute and extrapolate scientific models to predict the future seem to have almost completely destroyed the reliability of:

        1. The UN’s global climate model and
        2. The Bilderberg SSM solar model [Solar Physics 3, 5-25 (1968)]

        http://adsabs.harvard.edu/full/1968SoPh….3….5G

        Moral: The reliability of computer model projections are inversely proportional to a.) political pressure and b.) number of adjustable variables.

      • When the history of this AGW fiasco is finally written one of the most interesting questions will be why the community chose the surface statistical model results over the satellite measurements, as the thing to be explained?

      • Easy answer, David, but a cynical one. There is more uncertainty in the surface model stuff with which to manipulate one’s own beliefs.
        ==========

      • “…manipulate one’s own beliefs…”? Where did I put my bag of medicinal peyote buttons? Or as Alice would say, the question is can you do that?

      • Choose wisely, my friend; choose the one that ‘does nothing at all’.
        ==============

      • Ooh, heck. Choose the one that ‘doesn’t do anything at all’.
        ===================

      • “When the history of this AGW fiasco is finally written, . . .”
        remarkable parallels will be found between:

        1. The UN’s global climate model [1],
        2. The Bilderberg SSM solar model [2], and
        3. The Greenspan/Bernanke economic model for the Federal Reserve [3]

        If writers of history are less prejudiced by political pressure than writers of AGW, SSM and Economics. However, the hero in “1984″ finally conceded to the power of Big Brother [4].

        [1] The UN’s IPCC Reports on Climate Change

        http://www.ipcc.ch/

        [2] Solar Physics 3, 5-25 (1968)

        http://adsabs.harvard.edu/full/1968SoPh….3….5G

        [3] The Federal Reserve

        http://www.save-a-patriot.org/files/view/whofed.html

        [4] George Orwell, “1984″

        http://www.online-literature.com/orwell/1984/

      • David, the 1979-95 period is sort of a denier’s sweet spot. Move up three years to the 1982-98 period and the sweet spot turns sour.

        http://www.woodfortrees.org/plot/uah/from:1982/to:1998/plot/uah/from:1982/to:1998/trend

      • Not at all M. You just need to back out the ENSO. And take the whole record. No reason to start in 1982. In fact the only warming is during the ENSO, as it is all flat before and after.

      • David, there was no reason to start in 1979 either, except for the fact there’s no UAH data before then.

        ENSO is supposed to be cyclical. Cycles don’t drive long-term trends. Do you think ENSO has been mislabeled and is something other than a cycle?

      • M. carey, oceanic/atmospheric cycles do have long-term trends. Solar cycles have long-term trends. Of course there are also time scales with no trends. Regarding the late 20th century and ENSO, there is certainly a positive trend.

      • Edim, are you saying the late 20th Century warming was just a result of ENSO?

      • M. carey, no I’m clearly not saying that. Positive ENSO trend is, just like the various global temperature time series, a representation of climate change.

        My take is that the cause of the change is mostly solar/orbital and oceanic oscillations. I don’t know what exact physical mechanism is at play. TSI variation seems to be too small. But even that is not settled.

      • Oceanic oscillations suffice to explain late 20th Century warming. Whether or not they are causal is not yet known.

        Show me the CO2 signal.
        ============

      • Edim, the ENSO index does show more red, lots of which is in that 1979-95 period when the OLS for UAH temperature anomalies is flat.

        http://www.esrl.noaa.gov/psd/enso/mei/

      • M: I have no theory as to why the ENSO coincides with the step up in temperatures. That is for the climate science community to figure out, if they ever get round to it. All I know is that there is no apparent GHG warming in this pattern:

        http://www.mediafire.com/file/a9tv9tad9e6216p/UAH_2011_06_19_two_regressions.pdf

        No warming until the big ENSO and none afterward, but the later flat line is higher than the former flatline. Science is suppose to explain stuff like this, what we see, not run off chasing preconceived theories. Climate science is standing on its head.

      • Dear M. Cary:
        Dr. Spencer is showing on his website a warming of 0.21 degrees centigrades in 31 years. That is 0.07 degrees per decade. Global warming is right on track, it is not as flat as a pancake. For more, please see the projection in my book posted on http://www.global-heat.net, Table-1, page 58, or Table-5A of Article-12, Earth’s Magic.

      • Nabil, the point is that that 0.21 degree warming all happens as a single event, during the big ENSO. There is basically zero warming from 1978-1997, and also from 2001 to today, but the second flat line is warmer than the first. Calculating a decadal warming rate across this big step is true, but very misleading. Science is about explaining the specifics of what we see, which in this case is a step function. I see no way for the slow buildup of GHGs to cause this single step in 31 years. Hence I see no evidence of GHG warming in this observed pattern. None.

      • Dear David,
        Among the things that I have learned in my engineering career is that mathematics that is based on the good and validated work of our forefathers does not lie. When the mathematics is supported by observation, then there is no way in the world it can be wrong. Consequently, there is global warming that is caused by us, no other. It will, however, end naturally without human intervention. We have to assess the option of doing nothing about global warming.

      • David, the 17-year minimum for winnowing out a statistically signficant signal is based on the surface records. The satellite data have more variance (much bigger swings during peak el Nino/Nina), and therefore require longer time periods to winnow out a long-term forcing signal.

      • Dr. Spencer is showing on his website a warming of 0.21 degrees centigrades in 31 years. That is 0.07 degrees per decade

        UAH global trend is 0.14C per decade. Visit the data page and scroll to the bottom under the ‘Globe’ column to get the latest decadal trend – also listed are trends for each hemisphere, land, ocean, poles, tropics etc.

    • Down thread, Tempterrain brings attention to a neat graphic on the way some see the global temperature trend.

      • Somebody colored outside the boxes with the blue crayon, but what about the red line makes you blame CO2? Twice previously in the preceding century and a half the temperature rose at that rate and CO2 was not rising.
        ==========

      • Kim, I wouldn’t expect the temperature to rise in lockstep with rises in CO2. If I did, I would have to believe temperature changes are entirely a function of changes in CO2. I’m may be dumb, but I ain’t that dumb.

      • Well, how much is temperature change a function of CO2 change? The evidence of three temperature rises in the last century and a half with the same slope certainly argues for a small relationship, if any, between the two.
        ================

      • “lag”

        Scientized term for “magic.”

        Andrew

      • Lag confounds the cause.
        Is the post a propter hoc?
        Moshe knows not that.
        ============

      • “Lag” means nothing without an identified mechanism for storing the energy and evidence and viable explanation for why the time element exists at all. Otherwise, Bad Andrew is correct.

        Off-the-cuff “nature can do anything, given time” isn’t science. It is just speculation.

      • I hit the “”post” button one sentence too early.

        I meant to add that saying nature can do anything is like saying God can do anything, because he is all-powerful – kind of non-falsifiable, don’tcha think?

      • “Lag” means nothing without an identified mechanism for storing the energy and evidence and viable explanation for why the time element exists at all. Otherwise, Bad Andrew is correct.

        I suppose you also don’t believe in capacitors, springs, and styrofoam.

      • Figure 4 shows changes in CO2 and global temperature over the 20th Century. After seeing that these two follow the same path, some AGW skeptics have turned red faced and some AGW deniers have been reduced to gibberish.

        http://www.skepticalscience.com/co2-temperature-correlation.htm

      • shouldn’t CO2 correlations be done using log? temperature has a better correlation with population than with log(CO2). Also, both CO2 and temperature lag population. Temperature does not lag CO2

        This indicates that the real driver of AGW is population. Realistically the only politically acceptable solution is to drive up the price of food through biofuels and REDD, thereby capping population through food supply.

      • M.carey, warmth increases atmospheric CO2.

        http://www.esrl.noaa.gov/gmd/webdata/ccgg/trends/co2_data_mlo_anngr.pdf

        We just had 6% increase in human CO2 emissions. How much it will be for 2011? I think 35 – 40 GtCO2. Let’s say it’s ~4.5 ppm. The annual growth rate of atmospheric CO2 will decline in the next years/decades, because of cooling and in spite of increased human emissions.

      • “I suppose you also don’t believe in capacitors, springs, and styrofoam.”

        Web, are you suggesting these things are in the atmosphere? lol

        Otherwise, irrelevant.

        Andrew

      • Bad Andrew,

        By questioning WebT’s example of springs, capacitors etc in illustrating time lags you are showing your ignorance I’m afraid.

        Perhap’s I can give you a simpler example. If you switch on your central heating on a cold winter’s day, you do have to wait for a time before the house feels warm. It doesn’t happen instantaneously.

      • lag and log.

        Before you can claim NO correlation you have to test the real theory. the real theory includes
        1. a log response
        2. multiple forcings
        3. lagged effects, like in every system with inertia

        you burned down a straw man kim.

        hint: the observations are not long enough to test the theory in the way you want to test it.

      • A log response of forcing to CO2 increase is a very important element to potential warming. We know that fossil fuel CO2 emissions are not increasing exponentially, which means that the exponential cannot cancel the log and the forcing can’t continue at a linear rate.
        ln(exp(kt)) = kt
        which isn’t happening
        ln(ct^N) = N*ln(ct)
        which will show an eventual leveling off.

        The uncertainty is whether some catastrophic effects come into play and of course the underlying concern is the large adjustment time of CO2 which does not allow us to do course corrections should the behavior change for the worse.

      • WebHubTelescope -

        I suppose you also don’t believe in capacitors, springs, and styrofoam.

        Which of the “capacitors, springs, and styrofoam” do I not see the mechanism for storing energy in? None of them. They are all very clear how the energy is stored. What is your point? If those are your answer, you have no point.

      • Which of the “capacitors, springs, and styrofoam” do I not see the mechanism for storing energy in? None of them. They are all very clear how the energy is stored. What is your point? If those are your answer, you have no point.

        All these capacitive models are simply modeled by first-order rate laws
        τ*dy/dt + y(t) = f(t)
        where f(t) is the forcing function and τ is a time-constant. y(t) is temperature in this case. The solution gives a lagged response for temperature. We can make it more sophisticated by putting in a diffusive spatial term to take into account the depth of the buffer.

        I made note to those analogies because this kind of solution is quite common among different disciplines.

      • “lag”

        Scientized term for “magic.”

        To a sufficiently ignorant climate denier real science is indistinguishable from magic. ;)

      • Re: “lag”

        FYI for you Warmers, flawed analogies and unsupported assertions may sound good to you, but scientifically they don’t demonstrate anything.

        Andrew

      • Re: “lag”

        FYI for you Warmers, flawed analogies and unsupported assertions may sound good to you, but scientifically they don’t demonstrate anything.

        Andrew

        What a load. The ocean is a heat-sink for crying out loud. The thing that you are typing on is attached to a box which has got this chip inside which has this thing with fins that acts to cool the chip by providing a sink for the heat that the chip is generating. There is also a fan that helps to cool the fins down.

        Are you crazy that this doesn’t show anything scientifically? Engineers do it every day. It’s just that the people that have done this math specifically for the global climate haven’t delivered it to your doorstep with a ribbon tied around it. Lift a finger and do some research.

      • M: But when temperature does not rise, in lockstep or otherwise, what then? As you pointed out, according to UAH between 1978 and 1997 there was NO RISE. Nor has there been any rise since 2001. Lag is not the issue. Jump is the issue. Just one jump in 30+ years? How does AGW explain that? It can’t.

      • I don’t know where you get the idea there has been just one jump in 30 years:

      • Temp: I get the idea here:

        http://www.mediafire.com/file/a9tv9tad9e6216p/UAH_2011_06_19_two_regressions.pdf

        No warming before the big ENSO and no warming after. Painfully simple.

      • David,
        David Wojick,

        Ok I see. You’ve got an idea. Its probably the wrong idea though. At least you need to air your idea and try to garner some support. You can’t just declare it all to be “painfully simple” and leave it at that. UAH is just one temperature record. There are others. RSS is also based on satellite measurements. Then there are the ground station measurements. Why doesn’t it show up in them if its real?

      • Temp, I am airing my idea here. I am not in the climate debate business anymore so it is all I have time to do. I have posted this argument on previous threads and will continue to do so. That should be sufficient.

        I do not accept that UAH is just one of many data sets. The surface statistical models are poor compared to real instruments, designed to measure the parameter of interest. I prefer real instruments to goofy statistical models using bad data (at least for the period when such instruments are available).

        As for RSS, it was cooked up by people who did not like the UAH results. I have no use for it. But it has been many years since I studied RSS. Don’t they use a climate model to adjust the data, or something?

        But if you want to claim that all data is equal then we don’t know if it is warming or not, or not much. It would be interesting to construct an uncertainty envelop, as defined by all the data sets.

      • Temp, I am airing my idea here.

        Your “idea” is not only wrong, it’s so embarrassingly stupid it bespeaks your nigh-total ignorance of basic science as well as basic statistics. That’s the fact of the matter.

        Since we’re both busy, we’ll leave it at that.

      • David, Robert and TT

        The RSS satellite lower troposphere record shows a warming trend from 1979 to today of 0.142C per decade.

        The UAH satellite record shows a warming trend of 0.139C per decade, so the two are almost identical.

        At first RSS showed a steeper trend than UAH, but it has been adjusted downward since then.

        RSS shows a middle tropospheric warming of only 0.087C per decade.

        The key point is that the troposphere has warmed more slowly than the surface over the same period (despite claims to the contrary by IPCC):

        0.170C/decade GISS
        0.163C/decade NCDC
        0.153C/decade HadCRUT3

        BEST is not directly comparable, since it only covers the land portion, while the other records are global (land and sea).

        Max

      • The surface statistical models are poor compared to real instruments, designed to measure the parameter of interest.

        It is obviously more due to the nature of experimental science and the problem space we are dealing with. The issue is and has always been that we are picking up delta deviations against a temperature record that can show rather large seasonal fluctuations. These are all real instruments, it is just that the occurrence of 30 to 40 degree seasonal shifts can make it hard to demodulate the changes in the average. And then on top of that, put in some multi-decadal periodicities and the problem gets more challenging. This is all due to disorder in the environment that we are trying to filter out to detect the absolute change.

        In more controlled situations, we can do things like demodulate a carrier off of a broadcast signal easily — in this case we have a fixed reference frequency and can encode the informational signal with error-correcting codes. This is a good analogy because the climate problem turns the reference frequency into a murky, mutating blob and the real signal has no internal codes that we can attach to.

        On top of that, the murky signal is also apparently compensated to a substantial degree by the aerosols that we are creating. The bane of all experimental science and all engineering development for that matter is having compensating errors. These are difficult to chase down (ever debug a software problem consisting of two or more bugs?) and demodulate the real signal of interest.

      • Ahh! I just noticed “perhap’s” !

      • That is just an anonymous surface statistical model, with a stupid animation superimposed, as per SkepticalScience nonsense. The UAH record DOES NOT SHOW THIS STEADY WARMING. What don’t you understand?

      • And for this graph using Hadcrut data why is the the warming trend for the thirty year period from 1970 to 2000 the same as from the pre Anthropological CO2 period of 1910 to 1940. Is not something unique supposed to be happening post 1950, when AGW is supposed to have kicked in. Should we not have seen a steeper rise in temperature were new forcings evident. This of course agrees with both skeptics and believers that there has been a general non anthropogenic warming since the LIA.

        http://www.woodfortrees.org/plot/hadcrut3vgl/from:1910/to:1940/trend/plot/hadcrut3vgl/from:1970/to:2000/trend/plot/hadcrut3vgl/from:1910/to:1940/plot/hadcrut3vgl/from:1970/to:2000

        And for trends only

        http://www.woodfortrees.org/plot/hadcrut3vgl/from:1910/to:1940/trend/plot/hadcrut3vgl/from:1970/to:2000/trend

      • We should have seen a steeper rise due to CO2 is if other forcings were exactly the same for both periods. Have you investigated to see if that is the case?

      • CMS

        http://www.woodfortrees.org/plot/best/from:1910/to:1940/trend/plot/best/from:1970/to:2000/trend/plot/best/mean:11/mean:13/from:1910/to:1940/plot/best/mean:11/mean:13/from:1970/to:2000/plot/best/from:1910/to:2000/trend/plot/esrl-co2/offset:-326/scale:0.016/mean:7/mean:11/to:2000

        To answer barry’s point, put in the part of the CO2 record WFT includes, scaled to emphasize correlation to temperature rise.

        As the 1970-2000 period is warmer than the 1910-1940 period, there may be some logarithmic relationship of CO2 involved.

    • Dr. Spencer’s temperature anomaly shows a warming of 0.21 degrees centigrades in 31 years. That is 0.07 degrees per decade. Global warming is right on track.

      • UAH global temperatures have been rising at 0.14C/decade. You can get that from the bottom of this data page from UAH.

        http://vortex.nsstc.uah.edu/public/msu/t2lt/uahncdc.lt

      • Nabil and Barry, the point is that that UAH warming all happens as a single event, during the big ENSO. There is basically zero warming from 1978-1997, and also from 2001 to today, but the second flat line is warmer than the first. Calculating a decadal warming rate across this big step is true, but very misleading. Science is about explaining the specifics of what we see, which in this case is a step function. I see no way for the slow buildup of GHGs to cause this single step in 31 years. Hence I see no evidence of GHG warming in this observed pattern.

      • The 17-year minimum to extract a long-term (anthropogenic) signal from temperature data applies to the surface records. There is more variability, particularly in satellite data, so you need longer periods. I wouldn’t use any less than 20 years. What you are looking at, David, is more function of stochastic noise than underlying trend.

        ENSO is not a forcing. Something else is responsible for the rise in temps, whether you characterise them as a jump or a trend.

      • Dr. John Cristy’s last paper shows 0.07 degree centigrades/deacade.

      • What really counts for global warming energy balance is surface water temperature rise, or Sea Surface Temperature SST rise. Because surface air has negligible thermal capacity.

      • Nabil, would you kindly provide a link to the paper you mean?

      • 0.07 degree C per decade. HORRORS!

        That is nearly 0.7 degree C per century. MY GAWD WE ARE ALL GOING TO DIE!

        Which “track” is it that you figure “global warming” is right on? Certainly not the IPCC track, which wildly speculates an order of magnitude greater rate of warming that that. Even the low ball IPCC estimate, the one that certain groups have taken as their proverbial line in the sand on temp change, is three times that rate.

      • Dear JJ,
        Based on mathematics and observations, presently global warming is 0.07 degrees C/decade. It will accelerate with time. At this rate of CO2 emissions, in 2050, global warming will be in the order of 0.14 degrees C/decade. Global warming will end naturally and without human intervention. Maximum sea level rise may not exceed 1.6 meters from today’s level and surface temperature rise may not exceed 3.2 degrees from today’s temperature. See the Antarctic Ice Core Data. Surface temperature never exceeded 17.5 degrees C in the last 600,000 years, and there is no reason why it would in the future. Mathematics is in agreement. Based on these, the option of doing nothing to global warming merits consideration.

  2. The real key here is not temperature but what is claimed to be driving it the levels of CO2, which has increased over the last ten years , and no one seems to dispute that . So its would appear according the AGW theory temperatures must have increased and that is were this argument comes in , for if they have not the AGW theory has some real problems .

    • Marcel Kincaid

      That would only be the case if there were no other factors that might temporarily reduce temperature … but there are.

      • So, the AGW meme is that when temps go up it is because of HUMAN-SOURCE CO2 and only because of human source CO2, but when it does not go up, it is because of some “other factor” – anything else, some unnamed “something else” – any “other factor” but human source CO2.

        Do I have that right? Sounds like a kangaroo court to me. It couldn’t possibly be that human source CO2 and the warming were not related in the first place, could it?

      • No, that is not the meme. Attribution is complex, but not too difficult for us lay people to understand considering the amount written on it in the semi-popular literature.

        Repeat after me: anything shorter than 17 years of global surface temperature data is not enough to determine anything about climate trends.

        That is, and will always be, consistent. If you’re talking about a decade, you’re talking about weather variability more than underlying signal. This is the case whether the putative trend shows warming, flatness or cooling.

      • barry

        You’d better be careful with that “magic 17 years” demarkation as proclaimed by the “wizards of climatology”.

        If the current temperature continues for another 6 months or so, HadCRUT3 will show a “no warming” trend since January 1998, or over 14 years (with only 3 years left to go).

        Will it be time to move the “magic 17 year” goalpost then?

        Max

      • Joachim Seifert

        Max, lets find out the statistical details about the “MAGIC 17 Years”, which Trenberth proposed, when the CO2fingerprint wil not be detected anymore!
        Lets celebrate in advance, the time left is 6 more years, and taken 1998 into account, even less……,,then 2015 is the year we shake off the burden of AGW….. The temp plateau remains the plateau, the hockeystick will give us a comfortable warmth throwing it into the fire……

      • It’s maths, not magic. Ignorance is no basis for opinion.

    • AGW theory is not practiced. never has. Soon as they claim “the science is settled” it stopped being a theory, and became dogma. Hence it was in trouble from that day forward. Temporary pause? Someone clairvoyant?

      • Richard –

        AGW theory is not practiced. never has. Soon as they claim “the science is settled” it stopped being a theory, and became dogma.

        You put that phrase in quotation marks Who were you quoting? You said “they,” Who are “they?”

        How many of them are there?

      • Every AGW faithful, including people like Gore, Suzuki, et al. One only has to google the phrase to get a multitude of hits. Are you now saying the science isn’t settled? Progress!!

      • Richard –

        Every AGW faithful, including people like Gore, Suzuki, et al. One only has to google the phrase to get a multitude of hits.

        Really?

        I’m sure, then, it won’t be difficult for you to link to a few quotes of when people actually said that? In particular, climate scientists?

        Here’s a source that says your wrong.

        http://en.wikipedia.org/wiki/User:William_M._Connolley/The_science_is_settled

        Do you have evidence to prove that your statements aren’t completely false?

      • That link is to the rabid propagandist William Connelly, and can therefore be ignored.

      • ‘The Man Who Corrupted Wikiburg’.
        ================

      • I saw and heard, with my own eyes and ears, John Prescott (no sceptic) utter those exact words on BBC TV (not a sceptic organisation)
        However, I can’t seem to find any web references to it – perhaps someone else can?

      • Suzuki is often heard stating “The debate is over about whether or not climate change is real.” He’s in a new video going around highschools where he says this. So the term “the science is settled” is any variation there of.

      • No before you go off on a tangent that Susuki is right the climate changes, Suzuki is making the common AGW error of assuming ALL climate change is because of our CO2 emissions. So to him climate change is AGW, no room for natural mechanisms.

      • Richard –

        You are on record as putting the comments in quotes. You are further on record as saying that “every AGW faithful” has made that comment.

        If you want to dismiss Connelly as a partisan, and thus unreliable, then you need to provide evidence for your claims.Should I consider it constructive that you’ve been unable to do so?

        You’ve said all one needs to do is use the Google to find multiple examples. Is it possible that you have over-stated the reality? If so, by how much is what you said an over-statement?

        I’ll ask you again:

        You put that phrase in quotation marks Who were you quoting? You said “they,” Who are “they?”

        How many of them are there?

      • Vince whirlwind

        ……

      • Connolley partisan? Perish the thought.
        ============

      • Joshua,

        I found where Al Gore supposedly says that exact line. Not sure what’s actually being discussed in this thread right now, but are these what you’re looking for, where people said “the science is settled”?

        http://www.npr.org/templates/story/story.php?storyId=9047642 (Al Gore says it before Congress, with accompanying audio)

        http://www.theatlantic.com/politics/archive/2009/12/copenhagen-the-science-is-settled-the-policy-and-politics-arent/31350/ (Marc Ambinder, assigning it to Copenhagen in general?)

        One thing I don’t see is actual scientists saying it. But a lot of talk to pundits have been done (Gavin on Fox for instance) where it could have been said, and would not be recorded (certainly can’t find transcripts for any of those pundit shows), and that might be where people are hearing this: pundits on TV and off hand comments?

      • Ged,

        the line is in the editorial, not a direct quote, and Gore doesn’t say it on the audio.

        If he did use the line, we don’t know the context. And as you point out, he’s a politician not a scientist. This is not corroboration for this alleged quote attributed to scientists.

        The other quote is from a media pundit, as you point out.

        I’m sure I have heard the phrase used once, maybe twice by a scientist somewhere, but it was in relation to something specific and uncontroversial (to the reality-based world), like that human industry has increased the amount of CO2 in the atmosphere, or that increasing the amount of CO2 in the atmosphere over the long term will cause temperatures to rise at the surface.

        That is settled science, and the phrase can be appended. i’ve never seen the phrase attached to concepts that are less certain, like the magnitude of warming from CO2 or regional effects.

        What will it take to get skeptics to lay off the rhetoric?

      • Ahh, here it is.

        “The science of climate change is settled to the extent that we know that the climate is changing and humans are the main cause, with potential disastrous outcomes in the future,” said Kevin Trenberth, head of the Climate Analysis Section at the National Center for Atmospheric Research. “But the science is far from settled in all of the important details about just how much, and where and when (all the regional manifestations, etc.).”

        http://www.livescience.com/16462-cern-neutrinos-climate-change-doubts.html

        The science is settled that the main cause of current climate change is human activity, according to Kevin Trenberth. Uncertainties lie in how much the climate will change and what will happen regionally, he also says.

        I guess the most reasonable quibble might be over the word ‘main.’

        But Richard Wakefleld is shooting blindfolded.

    • “The real key here is not temperature but what is claimed to be driving it the levels of CO2″

      I agree but we get ever distracted by “skeptics” denying the warming itself.

      • If by that you mean people asking for valid data that proves there has actual been warming they your right , but I have a feeling you don’t and that the real problem for you is that people just don’t ‘believe’ no matter what the data says .

      • When are you people going to get it. We do not deny what the evidence shows. Distinct “warming” phases occured. We challenge the assumption that that warming is only because of our CO2 emissions. Climate science has NEVER made that connection, only infered it. Hence Trenberth’s attempt to redefine the null hypothesis.

      • “We do not deny what the evidence shows.”

        A lot of you do

        “We challenge the assumption that that warming is only because of our CO2 emissions”

        There is no such assumption.

      • It is very unlikely that the 20th-century warming can be explained by natural causes. The late 20th century has been unusually warm. Palaeoclimatic reconstructions show that the second half of the 20th century was likely the warmest 50-year period in the Northern Hemisphere in the last 1300 years. This rapid warming is consistent with the scientific understanding of how the climate should respond to a rapid increase in greenhouse gases like that which has occurred over the past century, and the warming is inconsistent with the scientific understanding of how the climate should respond to natural external factors such as variability in solar output and volcanic activity. Climate models provide a suitable tool to study the various influences on the Earth’s climate. When the effects of increasing levels of greenhouse gases are included in the models, as well as natural external factors, the models produce good simulations of the warming that has occurred over the past century. The models fail to reproduce the observed warming when run using only natural factors. When human factors are included, the models also simulate a geographic pattern of temperature change around the globe similar to that which has occurred in recent decades. This spatial pattern, which has features such as a greater warming at high northern latitudes, differs from the most important patterns of natural climate variability that are associated with internal climate processes, such as El Niño.

        - IPCC AR4

      • “It is very unlikely that the 20th-century warming can be explained by natural causes. The late 20th century has been unusually warm. Palaeoclimatic reconstructions show that the second half of the 20th century was likely the warmest 50-year period in the Northern Hemisphere in the last 1300 years.”
        Unlikely.
        One aspect which inescapable, glacier ice is at most couple million years old. And most permafrost is few thousand years old- some are tens of thousands of years old.

      • “We do not deny what the evidence shows.”

        A lot of you do

        Not true. VERY few of us deny that warming has occurred. It was, in fact, occurrign since 1800 and the end of the Littel Ice Age. From the little logic I have at my humble disposal, I have always understood that when ice ages end the temps rise. Please correct me if I am wrong on that.

        Once in a while that thought crosses my mind that warming has not occurred, but only because of the massaged data and the Climategate emails that show IN THE CODE that upward adjustments in recent decades were made – and downward adjustments were made in previous decades. I don’t trust the data. I don’t coice that doubt out loud, because I know that even in the skeptical camp it is not really accepted, and I don’t want to put it out there – because some AGW person might point at me and say, “SEE? A skeptic who doubts warming even exists!” and then ALL the skeptics would have to answer for my doubts (which is really about the fudging of the data, not warming itself).

        Dr Muller has (even since the BEST report came out) a terribly scathing opinion of the CRU/Mann behavior shown in the emails. I don’t think he has said so specifically, but it seems pretty obvious that the reason that BEST was undertaken in the first place was to get the data straight, once and for all. He has said he doesn’t trust the science by CRU and Mann. He had the means and the people, and he vetted the data. If it had turned out differently, you’d be hearing an earful from more than just skeptics!

        But PLEASE, if you have a name of someone on the skeptical side who has denied that warming (from SOME source) has occurred, please let us have it.

      • “VERY few of us deny that warming has occurred.”

        “Once in a while that thought crosses my mind that warming has not occurred, but only because of the massaged data and the Climategate emails that show IN THE CODE that upward adjustments in recent decades were made – and downward adjustments were made in previous decades.”

        None of that was ever true. You’ve been fed lies by those who deny the evidence. If it was true that Jones and Hansen had adjusted recent data upwards and past data downwards then BEST would have found less warming in recent decades and more warming in previous decades.

        “it seems pretty obvious that the reason that BEST was undertaken in the first place was to get the data straight, once and for all.”

        The data was already straight. Muller was taken in by the lies of those who deny the evidence. Remember he stated he was “surprised” that the BEST results matched GISTEMP and HadCRUT. That’s because the lies had made him expect his result would be different.

        “But PLEASE, if you have a name of someone on the skeptical side who has denied that warming (from SOME source) has occurred, please let us have it.”

        Joseph D’Aleo and Anthony Watt’s:
        “Instrumental temperature data for the pre-satellite era (1850-1980) have been so widely, systematically, and uni-directionally tampered with that it cannot be credibly asserted there has been any significant “global warming” in the 20th century.”

        That was the first point made in their “SUMMARY FOR POLICY MAKERS” in their 2010 “SURFACE TEMPERATURE RECORDS: POLICY-DRIVEN DECEPTION?” SPPI report.

        And now these same guys want to pretend they weren’t denying the warming. The thing is Muller remembers what he was being told by them. He remembers that “skeptics” were denying the warming. THat’s why he came out with his “end of skepticism” thing. Because once he found out through BEST that the data did show warming over the 20th century he simply applied that to what skeptics had been claiming.

        By “skeptics” didn’t like being publicly shown to be wrong so they complained that none of them had denied the warming in the first place, or as you have done claim that very few argued it.

        The fact is none of you know what you believe. You are just being contrary in order to deny AGW at all costs. Hence skeptics are extremely adamant there was a very cold and global little ice age, but from the other side of their mouth they will rubbish all lines of evidence like tree ring reconstructions and the instrumental record that are needed to make such an adamant claim about the little ice age.

      • Re: lolwot | November 6, 2011 at 6:42 am |

        Please explain how our emissions of CO2 have made summers cooler since the 1930′s. The vast majority of record highs in Canada are before the 1950s. The number of heat wave days has been systematically falling since the 1930s. Explain that. Second, there is no physical evidence that CO2 emissions are the cause of this warming. It is physically impossible for our CO2 emissions to have caused the rise in temps from 1850 to 1945. The ONLY period you can have any potential claim to AGW is that short period from 1975-1988.

      • lolwot:

        Instrumental temperature data for the pre-satellite era (1850-1980) have been so widely, systematically, and uni-directionally tampered with that it cannot be credibly asserted there has been any significant “global warming” in the 20th century

        How exactly do you interpret this to mean, “there has been no warming”?
        Methinks you need some extra lessons in English comprehension.

      • Lolwot -

        None of that was ever true. You’ve been fed lies by those who deny the evidence.

        I have seen the code myself. For example:

        yrloc=[1400,findgen(19)*5.+190 4]
        valadj=[0.,0.,0.,0.,0.,-0.1,-0.25,-0.3,0.,-0.1,0.3,0.8,1.2,1.7,2.5,2.6,2.6,2.6,2.6,2.6]*0.75 ; fudge factor…

        That is from Climategate file _____. It adjusted temps not at all in the early periods in question, then by small amounts down and up, and then in the last 9 periods adjusted the data upward by more than the warming since 1900. This is them condemning themselves with their own work.

        Joe d’Aleo and Anthony Watts in their paper?

        …Your confirmation bias is showing. You hold skeptics up to a different standard than those on your side of the aisle. And in this case you don’t seem to be able to understand the difference between believing that warming exists and the assertions that there was evidence that the researchers were playing fast and loose with the data. The two are not the same thing (although you conflate them to be).

        The data was already straight. Muller was taken in by the lies of those who deny the evidence.

        No. At some point someone had to vet the data and methodology, and look at more than 20% of the data available. You are confusing vetting with being taken in. Your confirmation bias is overwhelming. You wouldn’t accept objective points of view under any circumstances.

      • (Again to Lolwot): I couldn’t find the file name and had “______” as a filler till I did. It is there, and I failed to find it before I sent and don’t have any interest in talking to someone who has no interest in objective discussions. You are convinced and nothing will get through to you.

      • Hence skeptics are extremely adamant there was a very cold and global little ice age, but from the other side of their mouth they will rubbish all lines of evidence like tree ring reconstructions and the instrumental record that are needed to make such an adamant claim about the little ice age.

        That’s what bothers me as well. All the evidence that skeptics use about colder climates in history are based on records kept by people in populated areas, which are spatially spotty in terms of the entire globe. Yet, the skeptics turn around and complain about current day temperature records where scientists actually made an attempt to geospatially distribute measurement stations.

        And the proxy measurements such as tree ring data try to do the same thing in looking at geospatial data yet they are met with lots of rubbish that you have observed.

      • The little ice age was real, there are more than enough references in here: http://www.co2science.org/subject/l/subject_l.php AGW faithfull are now the deniers of the scientific evidence for a Little Ice Age.

      • Richard,

        Thanks for the laugh. Got any scientific sources for your assertion?

    • KnR,

      To help you answer your own question I would suggest you consider the scenario that temperatures in the 19th Century were rising at 0.2 degC per decade.

      If you add that warming to the above graph, what would it look like? How many periods would there have been when our forebears could have fooled themselves into thinking that temperatures were flat, or even cooling, and there was nothing happening to the climate?

  3. We are cooling, folks; for how long even kim doesn’t know.
    ================

    • The top was ’05-’06, and it’s the sun wot dunnit, Son.
      =============

    • Marcel Kincaid

      Solar activity has been at a minimum, so it can’t be “the sun wot dunnit”. Of course, as we come out of the solar minimum and “We are cooling” becomes obviously false, you will happily abandon that but stick with “the sun wot dunnit”. That sort of selective attention to evidence is what we get from “skeptics”.

      • I’m guessing you’re slightly unfamiliar with Kim’s comments. Leaping to interpretative conclusions can lead you astray.

      • TNX, A. It’s the Oceanic Oscillations and the Cheshire Cat Sunspots, HoneyBunch.
        ========

      • Marcel, “sunSPOT” activity has been at a minimum. “Solar activity” is comprised of a lot more than sunspots. Solar irradiance, for example, has neither been significantly up nor down, and most climate scientists argue that solar irradiance is not a factor at all in the climate (to which I disagree, as a conclusion, since I think they define it too narrowly).

        I don’t see so far any comments about the CERN cosmic ray-cloud formation evidence/confirmation and the effect of lower clouds and their cooling effect.

        As usual, climate scientists and their fellow alarmists want to look at things in the most simplistic way possible, re an extremely complex and chaotic phenomenon called climate. It isn’t just (pick one) CO2, nor “solar activity,” nor ENSO, nor PDO, nor AMO, nor oceanic sequestering, nor human activity, nor natural cycles, nor still coming out of the Little Ice Age (talk about “lag”! – a ref to upthread comments).

        Models and their output? In 1990 we were being told that they had covered all the bases in the models – then in 1997 the PDO was discovered, then later the AMO, then the CERN experiments, so the 1990 models couldn’t possibly have been correct (lacking the future knowledge of those and more), so the models then were wrong. In the future other factors (I won’t call them forcings) will come along, and today’s models will be wrong, too. But will climate modelers admit it?

        For a one-off simple-minded idea, to me the inclined sine-wave oscillation theories (I’ve seen several) seems to explain it all the best. It is right there in every graph we see. It argues that the incline is from coming from the ending of the LIA (that is what happens after ice ages, after all), and that we have natural oscillations over approximately 20-30 years since its end about 1800 – the very start (and low point) of the BEST land graph. Why the oscillations exist seems like a reasonable direction for research, but they are there, with their steep upslopes and their ‘pausing’ downslopes. It may or may not be correct, but it is falsifiable I think. But what it DOES do is explain (agree with) there being a current pause – which no other meme seems to do. The pause caught the CRU/Mann/IPCC side completely by surprise, and the skeptics didn’t see it coming either (though they prayed for it).

      • We know that the sun has a relatively constant intensity with a large variation in frequency. The climate science “energy budget” assumes that climate is only sensitive to intensity, not to frequency.

        This in itself is likely a wrong assumption, because it ignores ionization rates and the effects on the atmosphere.

      • “most climate scientists argue that solar irradiance is not a factor at all in the climate”

        From whence comes this delusion? Can you support this “fact” with proof? Would you agree that if you can’t, it’s reasonable to assume that all of your claims are similarly baseless?

      • Clearly most climate scientists discount solar iradiance as a significant factor, since they – the ‘consensus’ – steadfastly adhere to CO2 as the control knob.
        This being common knowledge, it seems resonable to assume all of Robert’s outbursts are similarly baseless.

      • You’ve a poor memory for Lacis’s recent statement that the solar contribution was cyclical and small.

        Who’s the President, Robert?
        =============

      • Get some rest, Robert. Your reading comprehension, your knowledge, and your logic are not up to your usual standard today. Mood, yes.

        Need a note?
        =====

    • I mention this downthread, but I was so surprised I thought I’d include it up here. I’m guessing it is what led Tsonis to his observations –

      http://www.woodfortrees.org/graph/hadcrut3vgl/from:1950/plot/hadcrut3vgl/from:1997.5/trend/plot/hadcrut3vgl/from:1950/to:1997.5/trend/plot/hadcrut3vgl/from:1950/trend

      We can say, quite meaningfully -

      a) There has been cooling for 14 years
      b) There has been warming for (more than) 60 years
      c) The rate of warming has INCREASED in the last 14 years.

      • Tsonis, the Famous,
        The discontinuous jump.
        Tell me what’s up, Doc.
        =============

      • Anteros

        When you say “quite meaningfully” do you mean ~55% meaningfully, or ~45% meaningfully?

        http://www.woodfortrees.org/plot/best/mean:13/mean:11/from:1976.5/plot/best/from:1976.5/trend/plot/best-lower/from:1976.5/trend/plot/best-upper/from:1976.5/trend/plot/best/from:1998/trend/plot/best-upper/from:1998/trend/plot/hadsst2gl/from:1976.5/trend/plot/best-lower/from:1998/trend/plot/hadsst2gl/mean:13/mean:11/from:1976.5

        Your (b) is meaningful at a really high level of confidence; however, confidence in your (a) is rock bottom, and (c) is debatable).

        a) HadCRUT is not very competent to provide a meaningfully confident trend on data less than 17 years. BEST is much better on such a short timeframe, and even though it’s only land temperatures, BEST both shows no evidence of having a significantly different trend since 1998 from the trend for the previous half century and also is generally consistent with rising (but slightly lower, though with significantly greater uncertainty) sea surface temperatures.

        But let’s look at kim’s solipsisms. Her tagline, “We are cooling, folks; for how long even kim doesn’t know.” As kim doesn’t know how long, there’s zero point to her tagline, since cooling, or almost any -ing, is dependent on period of time. (Here you go, kim, a link to a lesson in English usage to explain all about that: http://www.englishpage.com/verbpage/presentcontinuous.html with my compliments. :) )

        The top was ’05-’06, and it’s the sun wot dunnit, Son.

        NASA says you’re wrong about that, kim.

        There’s no evidence solar variability is the sole cause of warming in the past century, and certainly not since satellite measures above TOA began to be compared to global temperatures. Does kim have evidence NASA does not? It must be extraordinary evidence indeed.

        Is it some other solar effect that doesn’t work through the ordinary chain of Sun->radiation->Earth, somehow involving sunspots and spooky motion at a distance? Well, that’d involve undiscovered forces that work in ways we’re entirely unaware of, akin to magic or psychic Cheshire Cat powers, which Occam’s Razor tells us to ignore until we have some evidence that such is in play, since we have a simpler explanation that doesn’t require us to assume such wildly speculative causes. So, that’s a big ‘NO’ too.

        Is it ocean oscillations? Certainly, there are ocean oscillations. Those are real things. (Which is surprising, given kim’s track record.) However, the patterns associated with ocean oscillations for all the time we have record keeping indicate the order of magnitude of the amplitude of their size is pretty small compared to the century of rising temperature we have experienced, and also that the ocean oscillations last 2-15 years, not over a century.

        How many major ocean oscillations would we need to all converge to add up to a century and a half of rise end to end?

        That’s a trick question, as the oscillations are epicyclic, and so must return a drop for every rise, and even in complex ergodic patterns won’t lead to a trend more than double their natural length. (You can check out the fractal dimensionality of multiple interacting dynamic systems if you like, kim. It’ll always be less than two, so that’s at most under ~4-30 years.)

        That’s the oceans. They’re off the list, too.

        And no, kim’s poetry is not making the thermometers rise, either.

      • Kyle Swanson, of Tsonis-Swanson, says AGW stays alive and well.

      • Occam suffices,
        Defers to God Apollo.
        Magic ignorance.
        ========

      • Albert make kim as simple as possible, but please no simpler!

      • Whet the razor sharp.
        Simply, kim is curious.
        Questions unanswered.
        =============

      • kim

        Here you go, I give you the gift of questioning, the mark that sets a questioner apart from a fibber. It looks like this: “?”

        Put it after the question you ask, to avoid soundling like just more Knowledge Intentionally Made-up?

        Yes.

        Do you see the difference?

      • Bart R.
        You make a fair point that I use ‘meaningfully’ quite indiscriminately. I gave the wrong impression. I don’t believe the three points I made are equally meaningful – far from it. Perhaps I could have said ‘we can just about get away with saying..’

        I cherry-picked the dates and the dataset just to make the point, which in fact is a ‘warming one’ hence my admission of surprise, and shock [I've not heard of this way of looking at the data before - perhaps I haven't been listening very well]

        My point was that even though it is (with a bit of torturing) not untrue to say ‘there has been cooling for quite a while’ it still allows for the upward trend to continue (obviously) but also that over the cooling period, the longer term rate of warming MAY BE INCREASING.

        It is an analytical point I had overlooked because I had never taken cognisance of the impact of an (apparent) discontinuity around 1998. I think it creates something of an illusion – for people like me.

        I am ‘sceptical’. I also have no doubt about the radiative consequences of increasing CO2 concentrations. I fully expect global temperatures in 20,30,40 years to be somewhat higher than they are now. The only meaning in a genuine change in the rate of warming is that the longer term trend provides a slight change in evidence for equilibrium climate sensitivity – perhaps there was more ‘internal variability’ associated with some of the late C20 temperature rise…

        I talked up the recent ‘cooling’ merely to make a point, which I admit, still surprises me.

        If there was only discussions of trends longer than, say, 30 years, there would only be point (b). However, we’re not like that and so are led astray.

      • Anteros

        Respectfully, yes.

        You’ve presented the key problem, a version of Yule-Simpson, with allowing very small samples to color one’s interpretation of larger datasets.

        The resolution of climate questions has a minimum, in the case of surface temperature somewhere below 17 years but certainly over 8.5 years, below which any shorter span is truly meaningless on its own.

        (These subclimatic timespans are not unlike subatomic distances applied to measuring the length of a coastline.)

        I doubt we’ll see in our lifetime enough resolution in the monitoring of temperature to get to that (whatever it is) theoretical minimum timespan for climate questions; however, I think going forward we are already at least for the land records below 17 years by a bit, though of course where the limits of resolution are not necessary, longer timespans up to the length of the effect are often going to produce greater confidence or a better context for discussion, if we want to avoid being led astray.

        And temperature is not the only game in town.

        Wind in all its forms is under-studied, ocean currents, solar tide and all the carbon cycle components, and ice and groundwater and soil microbes and clouds and deep water and each with its own resolution on the global scale.

        Our scepticisms are differently formed; I come at this from what Chaos Theory tells me to expect of components and perturbations in complex systems, and count temperature as only one small part of the whole, and that only recently made very useful by BEST.

        Compared to the almost inescapable Chaos implications, temperature is just small change from my point of view. Slightly larger since BEST was completed, but still not the whole picture.

    • “…..even kim doesn’t know.” ??

      I’m not sure that Kim even knows which side of a graph is up !

    • Judith
      Re Pause?
      Anthony Watts posted:
      NCDC data shows that the contiguous USA has not warmed in the past decade, summers are cooler, winters are getting colder Burt Rutan sent Watts “Winter Trends in the United States in the Last Decade” showing the winter decadal trend from 2001/02 to 2011/10.

      ALL regions showed cooling, ranging from -1.34F/decade to -8.74F/decade. See Cooling Trend Figure

      Summer temperatures and trends °F, 2001-2011. Note that every 5 of 9 regions have a negative summertime trend.

      Only 1 of 9 regions has a positive decadal trend for the Annual mean temperature, the Northeast.

      “But most importantly, the trend for the CONUS for the past 10 years is not flat, but cooling. . . . So according the the National Climatic Data Center, it seems clear that for at least the last 10 years, there has been a cooling trend in the Annual mean temperature of the contiguous United States. . . . Given the NCDC data for CONUS, it certainly seems to me that warming has stalled for the United States in the last decade.”

      That appears to be a “Pause” for the last decade.

      • Global/regional, apples/oranges

      • barry
        The US has the most records and it shows flat to cooling.
        What evidence do you provide that the rest of the world was not similar within the range of uncertainties?

      • It’s possible that every region was ‘similar within the range of uncertainties’, but that wouldn’t change the point. Regional temperature trends are not a good proxy for global.

        Eg, even over a 30-year period (statistically significant WRT climate change), the range of decadal trends starts at -0.05C for the South pole, and is greatest at 0.45C at the North pole. The tropics are at 0.07C, the globe at 0.14C, and the US is 0.20C. (See bottom of page (here). The more localised the temp record, the more variability.

        Over the period of a single decade, not only is the trend even more susceptible to regional variability, the trend itself is not statistically significant.

        The apparent ‘pause’ or ‘slowdown’ in temperatures is a measure of internal variability over periods of less than 20 years. This is not to be confused with the long-term trend, which needs longer term data to establish. Judith and Richard Muller make that clear(ish) in their joint statement recently.

        If you’re talking about a change in the rate, trend of warming, or even just say that ‘warming has slowed’ in the context of the general discussion about global temperature records, you are implying something about a change in trend. This is a property then of statistics, and rigorous statistics must be applied. No statistical test can determine a change in the pace of global warming from 10, 13 or even 15 years of data. 30 is the classic period, but 20 will do. Regional data of short duration are even less informative.

  4. I agree that the last thing you should do with such a question (e.g. your original one) is to attempt to answer it. Immediately, you grant it a validity and meaningfulness that it doesn’t necessarily deserve.

    You go further – to break down the question a little and to tease out some hidden assumptions, but I think it is necessary to go further – if you spend 90% of your time getting the question right, the answer will usually fall into your lap. What the right question is may depend on our perspective (or, shock horror, our agenda…)

    I notice that you don’t mention the satellite datasets. Is there a reason for this? I vaguely assumed they at least could be useful in talking to the differences between the other records.

    I also think looking too hard at data such as the temperature record leads to trying to find discreet and dichotomous meaning in a messy analogue picture. I don’t doubt that we have strong motivations to stand and stare, but that shouldn’t convince us there is necessarily anything definitive to be seen.

    In contrast to the above, I do feel that those decrying the relevance of a 15 year period of measurement forget one thing. It is only what it is – 15 years is 15 years. Undoubtedly though, it is the MOST MEANINGFUL 15 years that we have.

    And finally, because I don’t wish to be so serious all the time, it is true that the IPPC-speak for the recent decade and a half {nearly..} is -

    “Although obviously we cannot derive significance from short periods of data, it is true that a cessation of warming for 15 years is what we would expect if Girma’s theory [see at various places on this blog] is correct”

    • Nicely reasoned, structured and well said Anterous!

    • But where have you got this idea that warming has stopped for 15 years? It’s completely false

      • relevant – not a single scientific paper that I can find that predicted “the pause” indicates warming would stop. If they had, we would be talking about a bunch of dead physics.

        Tsonis-Swanson – AGW cooks along while being suppressed and resumes dominance.

        Smith et al – in initial years natural variation clobbers AGW, and then half of the years after 2009 will exceed the 1998 record.

        Keenlyside et al – ditto

      • Is there any evidence of warming dangerous to humans? What?

      • I thinks it’s fairer to say it’s ‘mostly false’.

        For those that are so motivated, a couple of datasets already show more than 14 years cooling. I am certainly willing to bet that both those (RSS and HADCRUT3) will show 15 years of cooling next summer. Don’t assume, though, that I see those facts as being particularly meaningful. I don’t. Far from it.

        This graphic makes my point which I’ve been arguing up and down this thread.

        http://www.woodfortrees.org/graph/hadcrut3vgl/from:1950/plot/hadcrut3vgl/from:1997.5/trend/plot/hadcrut3vgl/from:1950/to:1997.5/trend/plot/hadcrut3vgl/from:1950/trend

        In this cherry-picked data -

        a) there has been cooling for 14 years
        b) there has been warming for 60 years
        c) the rate of warming HAS INCREASED in the last 14 years.

        It is counter-intuitive but true.

      • UAH shows 14 years of cooling from Jan 1980 to Dec 1994. Did it mean the global climate was cooling? Hindsight solves that one. Then there is 14 years of warming from Jan 1998 to Dec 2010 (12-month periods, people, not partial). Does that by itself tell us the globe is warming? No.

        http://www.woodfortrees.org/plot/uah/from:1980/to:1995/trend/plot/uah/plot/uah/from:1998/to:2011/trend

        Neither of these trends are statistically significant. Statistical significance is the elephant in the room in this discussion, and bandying words like ‘meaningful’ and ‘significant’ only muddies the waters. Those terms are rhetorical; statistical significance is mathematical.

        For us lay people, we can be simple about this – less than 17 years of global surface temperature data means the result is not going to be statistically significant – you can’t say anything about trend or trend changes with too-short time frames. If you do, you will be emphasising the noise in the data over the signal, whether you mean to or not.

        (Satellite data may need more than 17 years, as it is ‘noisier’ than the surface records)

        Judith’s observations on post-1998 temperature ‘trends’ are not statistically significant. This much is so (until such time as Judith produces some original work to explain how).

      • Barry, there is nothing in the math of statistical significance regarding time frames. The 17 year number is an hypothesis cooked up by Santer, based on the assumption that the variability in the long term surface statistical models is random. This is a strong empirical claim and no reason to accept it. As with much of AGW, it is just a conjecture, nor does it apply to the UAH data, because these contradict the surface data.

        More deeply, statistical significance is not a well defined mathematical concept, but there are certain conventional definitions. Under the proper experimental circumstances a nanosecond trend may be significant.

        Part of the confusion here is that normally the result of “no change” cannot be statistically significant, as it is the null hypothesis. Thus the lack of warming in UAH prior to 1998, as well as after 2001, is not statistically significant, but it is extremely significant physically. I believe it is sufficient to falsify AGW.

  5. Has anyone read this?
    I Mahlstein1,3, R Knutti1, S Solomon2 and R W Portmann2

    Abstract. The Earth is warming on average, and most of the global warming of the past half-century can very likely be attributed to human influence. But the climate in particular locations is much more variable, raising the question of where and when local changes could become perceptible enough to be obvious to people in the form of local warming that exceeds interannual variability; indeed only a few studies have addressed the significance of local signals relative to variability. It is well known that the largest total warming is expected to occur in high latitudes, but high latitudes are also subject to the largest variability, delaying the emergence of significant changes there. Here we show that due to the small temperature variability from one year to another, the earliest emergence of significant warming occurs in the summer season in low latitude countries ( ≈ 25°S–25°N). We also show that a local warming signal that exceeds past variability is emerging at present, or will likely emerge in the next two decades, in many tropical countries. Further, for most countries worldwide, a mean global warming of 1 °C is sufficient for a significant temperature change, which is less than the total warming projected for any economically plausible emission scenario. The most strongly affected countries emit small amounts of CO2 per capita and have therefore contributed little to the changes in climate that they are beginning to experience

    • This is just unsubstantiated speculation. It is irrelevant to the topic.

      • Harsh but fair

      • Marcel Kincaid

        Dishonest and unfair, as usual.

      • Meh, since he said ‘We also show that a local warming signal that exceeds past natural variability is emerging at present, or will likely emerge in the next two decades, in many tropical countries’, he has honestly said nothing. Heh.
        ================

    • Sounds like a paper sure to get Michael Mann’s approval to get another grant. It is all about the grant money – “how can we keep the gravy train going till we retire?”

  6. I would really like to see an analysis of how CO2 was supposed to have continued the warming against the break in the general trend from the 80s to 1998. If, as the IPCC suggest, the warming during the late 20th century was mostly due to CO2, and breaks in trends up to 1998 could be attributed to the 2 major volcanic eruptions, then the break in trend (however statically insignificant) ought to be accounted for.

    Also, I note that human emissions have been increasing, but atmospheric Co2 has not been accelerating. It’s almost as if we have been trying to help a truck pull it’s load by pushing. Since CO2 has been increasing, then surely combined with positive feedbacks, there should not be a question of temperatures slowing their increase?

    But I have another question – I note that despite what appears to be a slowing temperature trend, atmospheric CO2 does not seem to have stopped increasing. In fact looking at the muna loa charts, the linear trend seems to be very resistant to any annual fluctuations of global temperature. Or am I missing something?

    • atmospheric CO2 rise is accelerating and it is expected to continue as long as human CO2 emissions continue rising.

      http://www.woodfortrees.org/plot/esrl-co2/compress:12/derivative

      • And CO2 has a huge inertia and associated latency because of its long adjustment time, and even if the anthropogenic CO2 forcing was stopped it would only slowly decrease due to the diffusive lag on the excess CO2 left in the atmosphere.
        What I find laughable about the skeptics arguments via cherry-picked pauses and questionable trendology is that everyone realizes that lags and latencies exist in the carbon cycle. You can’t see those via data alone and that is why climate models are so important.

      • WHT, thanks for your reply. I am quite interested in ‘lags and latencies’ in the carbon cycle, but I did not find your reply quite informative enough. How long are those lags and latencies? How certain can we be that they are accounted accurately in models? I have spent some time reading up on this (just scratched the surface) but I can’t find anything that resembles a definitive answer – yet. To be honest it looks like guess work so far. Mostly it is inference based on assumption, which always makes me feel skeptical. FYI I started with AR4 and followed the refs.

      • lolwot, that is a very strange looking graph. Instead of fiddling with it just look at a normal plot:

        http://www.woodfortrees.org/plot/esrl-co2/from:1950

        It’s very linear and monotonic. There is no acceleration and no decceleration. I find this curious from an agnostic point of view. If the climate was as sensitive to co2 as has been suggested, then shouldn’t natural variability be better constrained by co2? And if global temps were driving co2 increases shouldn’t co2 increase show at least some correlation with temps, with a slight reduction in trend now?
        The gross co2 flux dwarfs human emissions which is why the co2 increase is linear – humans merely contribute. So it doesn’t satisfactorily explain the lack of temp signal in co2 in the atmosphere. It would be pretty unlikely that a slowing of the temp trend would be exactly matched by an increase in human emissions such that it would keep the rise so linear.

      • The accumulated fossil CO2 emissions are twice the gradient you see in your graph. This is an important thing to consider in attribution.

      • Well I can see the acceleration in that graph. It’s not linear at all. Go get the edge of a book or something else that’s straight and try to fit it.

        The graph I posted was the annual change. It’s increased over time, which means it has accelerated.

      • It’s a very slight increase. More remarkable for it’s linearity.

      • Or how about a more accurate representation:

        http://www.woodfortrees.org/plot/esrl-co2/mean:12/derivative

      • Why is this more accurate? What is ‘derivative’ doing? What is wrong with the interpolated mean?

        Am I to assume that ‘derivative’ is showing the raw data plotted as opposed to the mean? If it is the case that the diffusion co2 is slow, then surely the mean is more adequate/informative?

        When you talk about temperature response to co2 then you really mean 2 things; the co2 itself plus the feedbacks. I don’t see why the co2 would not have an immediate effect in reducing outward LW radiation, and I would have thought the response of feedbacks esp clouds would not be too far behind. I’ve read a lot of literature on this subject and I really don’t have a clear picture. The reduction in albedo is the single most important feedback cited, which is why the arctic gets so much attention. But NH snow extent is also important. The issue is that a warmer climate reduces the extent by making winters shorter thereby reducing albedo.
        I’ve studied this closely and I have noted step changes similar to those described by David W and his reference to the UAH. But the step I noticed was most dramatic in 1988/89 after which variability in extent was much more tightly constrained and began slowly to increase – certainly long enough to be significant.

        Returning to my main question, I appreciate that there maybe lags or latencies that even out co2 increase but there is not much discussion of a mechanism for it.

      • Latimer Alder

        @agnostic

        This is climatology. Please wash your mouth out for discussing ‘physical mechanisms’. These are the guys who can discuss the effect of ‘teleconnections’ on tree rings with a straight face and no apparent shame.

        Talking about physical mechanisms to a climatologist is like asking a priest exactly what chemistry the wine takes to become christ’s blood in transubstantiation. It is a question that requires belief, not explanation. Just believe……..

      • The derivative, applied to the 12-month mean, is really the annual change, ie the rate of change of CO2 concentration. The 12-month mean is to eliminate the seasonal changes.
        I just posted that graph because lolwot’s efforts do not give a true picture

        @Latimer, I think you’ve confused me with someone else.

  7. “Has the rate of warming continued unabated, or has there been a pause in the warming?”

    It all depends on the timescale. We are cooling since the Holocene optimum. We are warming since the LIA. We are cooling since the ’97/98 El Nino anomaly…

  8. Edit:
    “blogoshperic analyses”. RU implying that bloggers are drunks? >:)

    BEST’s data isn’t different from GISS because it is GISS, sliced slightly differently. It cannot therefore “allay concerns”.

    • It is different from GISS. For example they use a different station selection, they use more stations, they use different source code.

      The time to be able to accuse Hansen and Phil Jones of cooking the books is well and truely over. Get over it.

  9. I don’t like paused. Dynamic systems are unlikely to pause. Shifted ala Tsonis is more accurate. Shifts don’t have to be up or down, they can be less up, up, more up, less down, down or more down, with perfectly neutral unlikely. So I would say a negative PDO with a positive AMO is a less up. A negative AMO would be less down. A negative PDO + AMO would be down and a negative PDO + AMO with weak solar a more down. We haven’t seen a more down yet, could be interesting.

    • True, true and ‘peaked’ may be more accurate given what some predict which is from 3 to 7 more decades of global cooling and for all anyone knows a descent into another ice age by the end of the century.

      • I’m a big fan of your optimism Wagathon, but can I have some of what you’re smoking to be able to see an ice age this century? ;)

      • Anteros, that would be the Rodney Dangerfield of climatic factors, surface/atmosphere thermal conductivity. That poor negligable influence only someone with a fluid dynamcis perspective might see. It’s the boundaries.

      • And, it may be o v e r d u e
        ..

        All anyone has to do is read a book a book by Charles Dickens to get a sense of what the climate might feel like.

      • This is the horrible irony, Wag; is there no cure for the fever but cooling?
        =================

      • All anyone has to do is read a book a book by Charles Dickens to get a sense of what the climate might feel like.

        Charles Dickens reminds me of the Victorian London made infamous for pea-soup smog brought on by coal burning and sensitivity to foggy conditions.

        Wangathon, you continue to be a horrible mouthpiece for whatever agenda you are trying to push.

  10. Judith, in what you’ve said, there is no scientific basis for saying warming has stopped. You give a criterion:
    “Here I define ‘pause’ to mean a rate of increase of temperature that is less than 0.17 – 0.2 C/decade.”

    OK, then there needs to be an estimate of the rate of increase over some period, and a test of whether it is significantly below your criterion. With short periods, it is hard to get that significance, as Phil Jones famously observed relative to zero. After that, the arguments about cherry-picking begin.

    • Nick, The 2nd last paragraph answers that.

      • Well, it’s no answer. The criterion is set at the average recent rate of rise, or maybe a bit more. So it’s saying that whenever you can detect a short term period when the estimate of the gradient drops below average, it’s a pause? No test of significance?

      • So you disagree with the opinions of the scientists in the greenwire article too?

        You are saying there is no pause? You are saying there is enough data to say there was no pause?

      • No, I’m saying that you need a test of significance, otherwise you won’t know whether your observation of a “pause” is anything special. I’ve analysed the application of this criterion here. For the BEST dataset, even this version of pause (a transient 0.17C/dec) is not met in recent years. For HADCrut it is, but is also frequently met in the past, so you can’t say that the current period is more “paused” than most others.

      • Dikran Marsupial

        If only someone had suggested to Prof. Curry that tests of statistical significance (or power) before… ;o)

        It seems to me to be bizarre that modern scientific method (for instance backing up your statements with tests demonstrating that they have statistically significant support from the data – where data is available and the test is easily performed) seems optional for those arguing against the mainstream position.

      • The significance of this ‘pause’, not demonstrable statistically, is that it has caused so much curiosity, so much revelation of ignorance, and has stubbed the toes of those racing toward carbon encumbrance.
        =================

      • Vince whirlwind

        No Kim. The significance of this “pause” is that some people’s arguments are so poorly grounded in fact that they must be backed up by choosing a time period starting with the outlier peak in 1998.

        This is not only dishonest and incompetent but also so incredibly transparent that I am amazed that it generates any sort of debate among people who should know better. Maybe you don’t.

    • Nick, it’s not just that the warming trend has declined, it is also that it has not accelerated. If the warming in the last part of the 20th century was due to CO2, surely even more CO2 would cause even more warming (notwithstanding the logarithmic reduction in effect). If the relatively lower temperatures than expected in this decade are due to natural variability that are not properly accounted for, then why can the previous increase temps also be due to natural variability.

      I do not really buy Fred Mooltens line that all of the forcings have been tallied up and accounted for leaving CO2 to do the rest, especially as temps have not continued the trend.

      I do agree that the trend change is not robustly significant, but it is growing in significance all the time. It’s divergence from what I think is the expected trend is significant, and if it continues then that has real implications for policy. Broadly speaking, the previous decade has lowered the multidecadal trend, but its the change in trends that interest me. If the lack of continuation of the previous warming can’t be accounted for, if there is no predictive capability within what we already know about climate, it makes no sense to be so conclusive about AGW, and therefore our policy decisions should reflect that uncertainty.

      If you say, well the world might suddenly warm hugely, so we need to mitigate, some one else might say, well the world might cool and that could be worse and mitigation would counter-productive.

      • There’ll be Hell to pay for being wrong-footed into disastrously mitigating a warming that isn’t happening instead of adapting to a cooling that is happening.

        Climate Science is in receipt of bills from the Devil Heself.
        =============

      • Vince whirlwind

        Oh, you great big alarmist, you.

      • Agnostic,

        There is no inherent requirement that warming should be constantly accelerating. The theory is that the underlying trend is dependent on the balance of forcing factors, both natural and anthropogenic, and the top-of-the-atmosphere energy imbalance.

        In terms of expectations you should check out GISS effective forcing estimates. Between 2000 and 2010 there is no clear net change in forcing (perhaps slightly negative), mainly because the decade begins with a solar maximum and ends with a solar minimum. That being the case the expected transient response to forcing is a zero trend. The only expected source of warming, therefore, is the equilbrium response to the already-existant TOA imbalance caused by past forcing changes. In terms of IPCC scenarios the one that best fits the bill over this short period is the ‘Stablization at 2000′ scenario, which projects ~0.1ºC/Decade. Obviously you’ve still got the problem that interannual fluctuations are likely to hide any such trend over short intervals.

      • Paul S | November 5, 2011 at 12:12 pm | Reply

        There is no inherent requirement that warming should be constantly accelerating. The theory is that the underlying trend is dependent on the balance of forcing factors, both natural and anthropogenic, and the top-of-the-atmosphere energy imbalance.

        Paul S,

        Thank you for begging the question. The natural physical phenomena (with the atmospheric CO2 increases included) imply there is no inherent requirement that the current slight sub-decadal cooling should not be constantly accelerating for multi-decadal scales.

        We do not know either way, but evidence is building that we had it wrong with anything more than insignificant climate sensitivities. The science is not converging, much less not settled. And that is good for the motivation of scientists to have more open solutions to the climate dynamic. These are great times to invigorate science away from the myopic vision of alarming warming from CO2 by fossil fuels.

        N’est ce pas?

        John

      • Vince whirlwind

        Calling natural variation “cooling” is completely wrong. There is no cooling.
        Neither is there any evidence to support your statement about climate sensitivity being insignificant. Or can you back that up with some published science?

      • Calling natural variation “cooling” is completely wrong.

        So cooling due to natural variation isn’t real cooling ?? Wjat is it exactly?

        There is no cooling.

        Other than that temperatures have ggone down slightly of late.

    • Maybe the range of the pause criteria gives her test of significance?

      0.2-0.17 = 0.03C per decade looks like the width of Judith’s null hypothesis interval for testing the significance of the 1998-present trend. In degrees/year, that band is 0.003C/year. Compared to the standard error of the distribution of 10 year trend estimates derived from the BEST data, I’d bet the significance of this pause test to be something like p=0.8+

  11. I think your original question (with respect) was very badly formed. The RATE of change is not something that we usually consider to be prone to abatement – it’s just the wrong concept.
    More importantly, your question is formed as an either/or? But of course that excludes most of the interesting possibilities.

    Your four subsequent questions still don’t address the heart of the matter – surely what we want to ask is, specifically, -

    ‘Has global warming slowed down?’

    [Pausing implies the likelihood of a re-start]

    And we can then get down to the details of each part of the question and then we might be in a position to ask whether the answer is meaningful – whether we should pay much attention to it.

    I am a little baffled about the whole nonsense of choosing ‘starting points’. Surely, we’re interested in possible trends starting TODAY. We want to know how far these trends persist into the past and how significant is that length of time.

    The answer to the question above ‘Has global warming slowed down’ is yes. The significance of the slow down? Not much, but think what people would be saying if the warming had been 0.35 per decade over the last 14 years. It would have been accorded ENORMOUS significance.

    My prejudices lead me to ask (noticing that it has been cooling slightly for some time)

    ‘For how long has it been cooling?’

    I choose my datasets with extreme care and can say (for RSS and HADCRU3) that the answer is ‘For more than 14 years’

    It is STILL not very significant (I don’t mean statistically) but it is still the most important 14 years that we have.

    • Using ‘significant’ as a qualitative term is just adding to the noise. Does no one here know how to apply tests for statistical significance? That is what is missing from Judith’s claims, and from this discussion. Anteros, you’re muddying the waters with your your choice of terminology. This isn’t (or shouldn’t be) a qualitative discussion. It should be quantitative. I wish I had the skillz to do it. Surely someone here does (Nick Stokes?).

      • barry -

        You’re right about me muddying the waters using ‘significant’ in a everyday sense. It was sloppy.
        I understand you calling for a simple use of statistical significance, and to an extent, share your view. However. there are many caveats, some of which have been elucidated by Davis Wojick hereabouts. My own view (as a gambler with an eye for odds) is that statistical significance is a purely arbitrary device. It says that there is up to a one in 20 chanbce of this occurring by chance. It is not actually saying very much. And the choice of 1 in 20 is regardless of the kind of phenomena we are looking at. It is not some kind of magic number beyond which the data speaks a different language. It is convention, nothing more.

        Having said that, my dichotomous mentioning of 14 years of cooling is also muddying – if not obfuscatory.
        Mostly on this thread I have been making the point that the questions around ‘what has been going on with temperature’ are by and large incredibly poorly formed. For example Judith’s opening question today – it is not worth asking let alone answering.

        See elsewhere on this thread for my emphasis on the seeming paradox between two true statements –

        a) It has been cooling for the last 14 years
        b) the rate of warming has ACCELERATED over the last 14 years.

        Using the same data (RSS or HadCRUT) both these satements are demonstrably true, and confusion reigns because we have no natural language conception with which to express them together. They come from two different perspectives that we don’t know how to bring together, hence the paradox.
        Bart R suggests it is a version of the YuleSimpson paradox, but I suspect it is subtly different.

  12. “What does the BEST land temperature data have to say about global warming? Not much, since the BEST data only covers the land (~30% of the global area). The BEST land data should not be used to infer anything quantitative about GLOBAL warming.”

    And yet Muller is in fact making quite definitive statements about the planet. He writes in his controversial WSJ piece:”Global warming is real.” How does he get away with this assertion given that he’s only talking about surface temps? What is the basis for what must be an inference… given he has no direct data?

    • I agree entirely. For such a sharp guy he really is a loose cannon. Is there anything at all in the recent controversy that hasn’t stemmed directly from something he’s said or written?

      I can’t see why the BEST dataset adds to the (global) satellite coverage.

    • I think he was talking to the people who have been saying the land record is manipulated and therefore AGW is a hoax.

      So maybe they’re manipulating the ocean record. You know, like losing at trench warfare: lose one trench, retreat to the next. Repeat, repeat, repeat.

      • Fair point.

        But he didn’t give the impression he was talking just to the oddities that think AGW is a hoax. He gave the impression that he was talking to ALL of us about ALL scepticism. No wonder some of us started throwing our toys out of the pram! :)

      • It’s not just a hoax. It’s also a scare tactic.

      • Ooh, I’m scared. That big bad wolf is really a lovable St. Bernard pup with aqua vita on board.
        ==========

  13. the long term trend is warming…

    The short term trend 1998 to present is cooling..

    One must look at many things when asserting cause.

    Ive been studying the sun now for four years along with the trends that occur with decade and multidecadle ocean flows. the funny thing is each hemisphere is acting like it is not connected to the other or polar opposites. at first is perplexed me but then i remembered that the earths “charge” is changing. WHAT HAPPENS TO ANY SOLUTION WHEN A MAGNETIC CHARGE IS APPLIED?

    Just one more forcing that they do not account for..

    Magnetism can make water spin opposite physical vessel rotation.( salinity and other components in the water either enhance or slow this)

    Earths flows are directly affected by magnetic changes. as the suns magnetic influence increases and decreases so will the earth respond. Competing fields can cause chaotic behavior..

    Solar fields have decreased.. Earths fields have decreased. Now for some reason the Pacific Deep Water Cold Return is amplified. yet 13 years of ice return and static levels in the arctic would cause little cold build up yet we have amplification? so much amplification that it is affecting flows around England and Europe. (poor saps are going to get pummeled this year again).

    Just for fun get a good quality magnet (bar) set it under a solution of salt water and some sand.(glass beaker – bar under the beaker) spin the water with a spoon then watch the granules fall. it will not fall evenly and depending on metals in the sand it will create a mound on the bar..

    WHY?

    take a closer look and you will find that the grains are all aligned by polarity. even weak fields cause disruption of water flows. As the water flow slows the fields cause redirection of fluid and particles in the fluid. even the human body using at MRI (magnetic resonance Imaging) uses this simple method to look into the human body. (aligns the molecule by polarity and then the release of the field allows the energy of the molecule to return to earth field orientation.. this releases energy that can be mapped. so how does the magnetic fields on the sun change the earths? how will it affect climate? flows?

    there are just to many unknowns to say that CO2 is the only cause…

    CO2 can not cause the warming they claim.. and when the earth acts in such a way that discredits their hoopla the spin machine is engaged.

    probably gibberish tonight but it is Friday… :p

    • I, for one, say Bravo to you Bill!!!!

    • Makes a lot of sense Bill. Its Saturday now but certainly feel free to partake of your favourite tipple any time.

    • Bill, this in fact is the factor that Piers Corbyn uses to make his long range forecasts. I hardly dare utter his name here, but some of his long range forecasts have been spectacularly accurate. Essentially he examines solar magnetic influence, the way it is modulated by the moon, and presumably along with other factors aligns this with historical weather patterns to infer weather likelihood.

      Recently the BBC set up some league tables to monitor how various independent weather forecasters performed against the MET office. Initially the met office were not interested in anything long term because they didn’t believe it was possible to accurately forecast long term, but Piers insisted that long range forecasting be included as he disagreed.

      Piers was invited to explain his methodology, but I don’t think he has done that fully (critics would say ‘failed’ to do so) presumably because he regards it as a trade secret. I do think that since he has survived selling forecasts and some of them have been spookily accurate, he might be on to something real enough to not discount out of hand.

      • Piers was invited to explain his methodology, but I don’t think he has done that fully (critics would say ‘failed’ to do so) presumably because he regards it as a trade secret. I do think that since he has survived selling forecasts and some of them have been spookily accurate, he might be on to something real enough to not discount out of hand.

        This guy sounds like a hero of yours, yet he is no hero, because he refuses to come forth with information that could counter all the AGW mass hysteria that you all think is damaging the economies of the world. If this info is so important then for the welfare of us all you should run a Watergate-style operation and dig something out of his drawers. I bet all you find is twigs and seeds.

        I am being sarcastic but this is actually what you people sound like when you go after climate scientists, with the caveat of outrage over public funding to disguise that it is just a two-bit witch hunt. Ha ha.

    • “The short term trend 1998 to present is cooling..”

      No it isn’t. Even if we were to entertain the incorrect method you used to determine this, the same method produces warming since 2000 and warming since 1996. What is so special about picking 1998 then?

    • you’ve got to be kidding me, talk about cherrypicking.

      As if by magic by changing just one year I can make your imaginary “shift” work in the complete opposite direction:

      http://www.woodfortrees.org/plot/hadcrut3vgl/from:1979/to:1998/plot/hadcrut3vgl/from:1998/to:2009/plot/hadcrut3vgl/from:1979/to:1998/trend/plot/hadcrut3vgl/from:1998/to:2008/trend/plot/hadcrut3vgl/from:2008/plot/hadcrut3vgl/from:2008/trend

      Explain why you choose to start your “shift” in 2009?

      • lolwot – I did not pick the years used in the graph. They was picked by Swanson, of Tsonis-Swanson.

        What Swanson said, which gets left out by every single person I have seen discuss this, is the shift could barely be seen on GisTemp. And this is a big problem. People who want to spout off about the pause, usually only want to talk about HadCrut. Swanson was honest. He discussed contrary evidence.

        So the point of my graphs is that the shift does not exist on GisTemp, and it does not exist on BEST land (not saying that in and of itself is pertinent,) But Muller said Best was closest GisTemp, which makes it interesting. Bart R., on another thread, laid out an argument for why BEST does say something about global warming, and I took A. Lacis to mean he did not think the BEST result will change once oceans are added, which just might mean GisTemp is going rise substantially in prominence. NOAA, too. I doubt the shift exists on NOAA.

        As it is, imo, anybody who presents graphs solely in HadCrut could be sweeping something under the rug.

      • Also, the part of the graph starting in 2009 is after the shift. Just a few months ago it was shooting straight up. Too short of period to mean anything at all.

  14. Judith,

    It’s like the recession…double dipping…

  15. Anteros writes: “For such a sharp guy he really is a loose cannon. Is there anything at all in the recent controversy that hasn’t stemmed directly from something he’s said or written?”

    This is my sense of the man as well. He’s all over the place. I no longer believe he’s some sort of Machiavellian schemer. He just seems reckless to me, saying and writing whatever occurs to him at the moment

  16. Judith, you are asking the wrong question. Too much emphasis, in fact it is the ONLY focus in AGW, is average temperature. Global average temperature is completely meaningless. It’s not a measurement, but a calculation.

    The correct question should be, has there been a shift in the range of temperature trends across the seasons since 1998? For example, the increase in average temperature from 1975 to 1998 was due to either no change in summer temps in temperate zones, or a drop in temperatures in the summer temporate zones, coupled with winters not getting as cold.

    If the winter temp increases faster than the summer decreases, the average will increase.

    If the average has stopped increasing since 1998, what season temperature has changed to make that average stop increasing? If winters warming slowed down and matched the summer cooling rate, the average will be flat. Yet the trend in yearly temp ranges hasn’t changed, summer and winter temps are converging just not as quickly now.

    So, what has changed with the seasonal temperatures world wide since 1998? That’s the real question.

    • Given that everything you say in the opening paragraph may well be true the climate probably is as it was in 1945…

  17. So what is the evidence for suggesting a ‘pause’ or even a ‘stop’ during the past decade or so?
    HadCRUT3 global temperatures (1998-2010) [link]

    I can’t see a thing from those three graphs. Don’t you have a better way of presenting the 1998-2010 data?

    Statistical analyses of various data sets over various periods aren’t all that interesting in the absence of an hypothesis that is related to a physical mechanism.

    I’m confused. You started asking whether there was a pause, but now you’ve changed the question to what is driving the climate.

    The reason there’s “much traffic for woodfortrees” is that it’s by far the best online tool for looking at GISTEMP etc. from a great variety of perspectives. (If you have a better one everyone here would love to know about it!)

    To illustrate how enormously the perspective colors the interpretation, compare the last decade with the last four decades.

    The first, combined land-ocean temperature index, covers the decade 2000-2010. The second backs four times as far away to take a longer range view, 1970 to 2010.

    For a fairer comparison, both graphs have been smoothed-and-sampled at rates designed to make both graphs deliver the same number of samples, namely 120 total. The first accomplishes this with 1-month (i.e. no) smoothing-and-sampling, the latter with 4-month smoothing-and-sampling. (Think of it as your eye having constant angular resolution: as you back away from the scene you can’t resolve details as finely.)

    It seems pretty obvious that the first graph shows the temperature going nowhere during that period.

    The second graph equally obviously shows a steady rise. There is no clearly discernible difference in the ups and downs in each decade. Some people, and maybe some tests, will find differences between the decades, but how meaningful would they be?

    Which graph is the more meaningful one depends on what question you’re asking (as you said). If you ask “was 2000-2010 flat” then the obvious graph to look at is the first one because it gives you a close-up look at that window. It sure looks like it’s flat.

    But if you ask “is there a pause?”, by which you mean has the rise slowed or stopped, obviously one can’t answer this without including the context. or you’d have nothing to compare with. When we compare this last decade with the three preceding decades for context, thinking of the latter as a fast-rising three decades, it’s hard to see how you could interpret the last decade as clearly a “pause.”

    I think skeptics just don’t like to look at context, because it tends to undermine the “pause” thesis.

    Ben Santer makes much the same point with his recent 17-year rule, which you can google for. You’ll notice when you do so that his rule has really roused the wrath of the skeptics, not surprising given the evident differences between the above two graphs.

    • There is no clearly discernible difference in the ups and downs in each decade. Some people, and maybe some tests, will find differences between the decades, but how meaningful would they be?

      Ah, silly me, I forgot that I could do at least one simple-minded test to reveal any possible differences between decades: just fit a trend to each decade. Here’s what you get when you do this.

      last four decades with decadal trends

      I must say I was really shocked. This decade is practically as steep as the preceding one, and both are considerably steeper than the two earlier ones!

      • I also found a way to shock myself.

        http://www.woodfortrees.org/graph/hadcrut3vgl/from:1950/plot/hadcrut3vgl/from:1998/trend/plot/hadcrut3vgl/from:1950/to:1998/trend/plot/hadcrut3vgl/from:1950/trend

        Even though the last 14 years have been completely flat (with Hadcrut..), to add them to the 1950-1998 data INCREASES the rate of warming. So people who say the rate of warming is increasing are sort of right.

        I guess this is what Tsonis is on about. An apparent discontinuous jump can create some very odd trend impressions.

      • I’m actually quite gobsmacked by this. Using data up to and from 1997.5 (cherry-picked just to get a cooling..) – more than 14 years ago, you can generate two true statements that at first sight are seemingly contradictory –

        a) the earth has been cooling for more than 14 years.
        b) the earth has been warming more than 60 years, AND THE RATE OF WARMING HAS INCREASED IN THE LAST 14 YEARS.

        http://www.woodfortrees.org/graph/hadcrut3vgl/from:1950/plot/hadcrut3vgl/from:1997.5/trend/plot/hadcrut3vgl/from:1950/to:1997.5/trend/plot/hadcrut3vgl/from:1950/trend

        I think everyone should look at this :) :) :)

      • Ya really gotta wonder how that temp leap in 1998 was connected with the Tsonis jump then.
        ========

      • Yes, staircases still go upwards even though the treads are flat!

        BTW, on Judith’s point about WoodForTrees; we can still handle the traffic, thanks :-) But you might be surprised to hear I agree with her about the relevance of looking for a physical mechanism and the danger of spending all one’s time looking at graphs – and in particular short-term trends! It’s good to hear people discussing long-term climate cycles again, that was the original point of WFT…

      • Anteros

        Now that I have my head wrapped around what you’re saying, I have to say excellent illustration of a fairly obscure effect.

        Well done sir.

        That the effect happens at different places for different datasets is also interesting. On BEST, your 14 years becomes 9.5 years, for example.

      • Your two early pauses were due to volcanoes.

        Had any of those lately?

      • ENSO phases

      • Hi V

        A decade is 10 years mate not 11. So lets try 1971-2010 with trends as follows; 71-80; 81-90; 91-00; 01-10

        http://www.woodfortrees.org/plot/gistemp/from:1971/mean:4/every:4/to:2010/plot/gistemp/from:1971/to:1980/trend/plot/gistemp/from:1981/to:1990/trend/plot/gistemp/from:1991/to:2000/trend/plot/gistemp/from:2001/to:2010/trend

        We see what we’d like to see, hear what we’d like to hear.
        We’re only human afterall.

        regards

      • A decade is 10 years mate not 11. So lets try 1971-2010

        Funny, I typed 2010 − 1971 into my calculator and got only 39 years. One of our calculators is broken and I’m thinking it’s yours. If you got 40 years I suggest you send your calculator in for repairs. If it’s still under warranty they should do it for free, nil bastardio carborundum (don’t let the bastards grind you down).

        Another way to check is to click on the raw data button for 1971-2010 and hit the End key to take you to the bottom. On the second last line you should see “468 samples”. 468/12 = 39 years. That’s how many years woodfortrees thinks there are in 1971-2010.

        We’re only human after all.

        The road to wisdom? Well, it’s plain
        and simple to express:
        Err and err and err again,
        but less and less and less.
        –Piet Hein

      • Alexej Buergin

        From 1 January 1971 to 31 December 2010 it is exactely 40 years; one does not need a calculator for this.

      • From 1 January 1971 to 31 December 2010 it is exactely 40 years; one does not need a calculator for this.

        True. And from 1 January 1970 to 31 December 2009 it is exactely 40 years also. One does not need a calculator for this either. What point are you trying to make here, exactely, besides attesting to your numeracy and orthography?

      • Alexej Buergin

        I just tried to explain to you why Baa Humbug (Nov 5, 12:23 am) is right and you are wrong (Nov 4, 9:47 pm).
        If you want to take a decade (and not be accused of cherry picking), you have to start with the first year, that is 1 (2001 in your case).

      • Folks, dates in WFT represent a point in time in floating point years. Hence 2010 means 1/1/2010, not 31/12/2010. I think what you want is either from:1970/to:2010 or from:1971/to:2011 according to your preference of when a decade begins (not that the climate cares about arithmetic modular to the number of carpal digits of one particular species, counting from the probably inaccurate birthdate of one particular religious figure ;-) )

      • Oh, and intervals in WFT are semi-open (from <= t < to) or [from,to)

      • If you want to take a decade (and not be accused of cherry picking), you have to start with the first year, that is 1 (2001 in your case).

        Oh, that never occurred to me. Ok, so then are you saying that if we follow my rule for picking decades of only allowing years that are multiples of ten when specifying ranges, the last decade warmed almost as fast as the previous one, but if we follow your rule of only allowing years that are congruent to 1 mod 10, per the fencepost error that makes the year 1990 part of the 1980′s, then the warming paused during the last decade?

        Old theory: CO2 causes global warming.

        New theory: defining “the first decade of this century” as 2001-2011 instead of 2000-2010 causes global cooling.

        So what is your real subtext here? That it’s meaningless to judge warming or cooling on the basis of just one decade, if a tiny shift of one year can make such a huge difference to the trend?

        If that’s not your subtext then your argument is right up there with the Easterbrook trick, which was to hide the warming under a vertical gridline by choosing a scale that made the plot 10,000 years wide, making gridlines a century wide. Logically one would center that gridline on the year 2000 so that it spanned 1950-2050 (sorry, 1951-2051, rap my knuckles with a wet noodle). By sliding the gridline half a century left or right one can now easily see that the MWP was half a degree warmer or cooler than “today,” respectively. Not surprisingly Easterbrook chose the former. Anyone sliding it to the right is obviously a cherry-picker. (Hmm, you just moved the 2000-2010 decade one year to the right by inappropriately applying a fencepost error, what does that make you?)

        This is all part of the rapidly developing science of climate skepticism, which is either a branch of physics or logic depending on who you talk to. One of the best tricks, due to Harry Huffman, who pipes up here now and then, is to prove that CO2 doesn’t cause global warming by arguing that if it did then the altitude on Venus where the air pressure is equal to that at Earth’s surface should be hotter than on Earth, since the atmosphere above that altitude has about the same mass as the whole of Earth’s atmosphere but is almost all CO2. And it is, but not because of the CO2 but because Venus is closer to the Sun. If you imagine moving Venus away from the Sun until its distance is as for Earth, and use the Stefan-Boltzmann law to compute what the temperature at that altitude would then be, it turns out to be precisely the same as at the surface of the Earth. So evidently the 97% CO2 atmosphere on Venus is not warming Venus any more than our 0.04% CO2 warms our surface.

        What’s wrong with this argument? Well, Venus absorbs only 10% of the incident sunlight, while Earth absorbs 70%. To even everything up Venus would have to absorb seven times as much sunlight, and that would make that altitude of Venus a lot hotter than Earth.

        Returning to the topic of this thread, the question of whether this last decade is showing a “pause,” let’s be generous and assume that your real subtext is the meaningless of a decade of data as indicative of direction of the climate. This is not news, by a long shot. 20 months ago (Feb 19, 2010), at http://tinyurl.com/RobbieSays15Years (a tiny url for this Amazon post), I examined all 3,120 windows of width a multiple of 12 months, from 5 years wide to 17 years wide, starting January 1979 or later and ending December 2009 or earlier, from the then-current RSS MSU dataset (satellite temperature data for the lower troposphere, which is what others had been using–note that the URL in the Amazon is no longer current, use the just-cited one instead).

        For each of the 13 possible widths, I asked what proportion of the windows showed a decline. Here are the results (n is the number of years in the window, starting with windows of width n = 5 years).

        n #Cool/#Possible
        05 150/312
        06 109/300
        07 84/288
        08 63/276
        09 40/264
        10 12/252
        11 16/240
        12 9/228
        13 0/216
        14 7/204
        15 1/192
        16 0/180
        17 0/168

        With five-year-wide windows, practically half showed a decline. With 15-year wide windows, only one showed a decline. 16-year-wide windows showed no decline, but to be on the safe side one should go with 17-year wide windows. (Back then I was less conservative and suggested 15 would suffice, but that’s obviously a bare minimum.)

        This conclusion from 20 months ago is in great agreement with Santer’s 17-year rule from this year, modulo exactly how conservative one wants to be, and of course modulo choice of dataset, which was not my choice but the dataset under discussion at the time.

        Disclaimers: I learned about Santer’s rule from Sebastian Thrun at our faculty lunch last Tuesday, who put me in touch with him. AFAIK Santer developed his rule entirely independently of me. This is yet another case where scientists both inside and outside the climate establishment have by close examination of the data, and in this case unknown to each other and working completely independently, arrived at essentially the same numerical conclusion. And judging by the number of people taking 10 years seriously, this is not an obvious conclusion.

        In my case I see in retrospect that I should have been making a bigger fuss over this. I’ll amend my behavior accordingly by submitting more of my climate work for peer review in the future. (Ah, but I can put that off until New Year resolution time, right after Santa’s month.)

      • (Hmm, you just moved the 2000-2010 decade one year to the right by inappropriately applying a fencepost error, what does that make you?)

        Fence Poset is constrained by partial order ( symmetry and transitivity) whereas Lorenz suggests (quite convincing) that climate is “almost transitive.” (and bounded by singularities)

        http://mathworld.wolfram.com/FencePoset.html

        The argument for a rabbit prooof fence ( 17 years) is odd,as no odd Fibonacci number is divisible by 17 (Honsberger 1985, pp. 132 and 242).Hence bringing disorder to partial order returns to disorder eg Pinatabo.ie and opaqueness of the window.

        Sensitive to initial conditions is whatever the initial conditions.

      • Alexej Buergin

        woodfortrees (Paul Clark) | November 5, 2011 at 12:21 pm |
        “not that the climate cares about arithmetic modular to the number of carpal digits of one particular species, counting from the probably inaccurate birthdate of one particular religious figure”

        Even if the BBC should really replace AD with “Common Era”, the fact remains that there neither is nor will be a year Zero. So the first year of the first decade of the first century remains year ONE.
        We all know why one counts differently when programming a computer.
        But the new Millenium started on 1 January 2001, and 2000 was the last year of the old one.

      • Vaughn Pratt: “What’s wrong with this argument? Well, Venus absorbs only 10% of the incident sunlight, while Earth absorbs 70%. To even everything up Venus would have to absorb seven times as much sunlight, and that would make that altitude of Venus a lot hotter than Earth.”

        Totally incompetent remark, Mr. Pratt (assuming you read my article), but par for the course for climate consensus defenders. First of all, it is not a matter of my analysis showing that Venus and Earth are “even” in absorbed solar energy (I won’t even go into your failure to take account of the two planets’ different distances from the Sun, with your glib “seven times”). I am a real (competent) scientist, and you obviously are not. I am shocked by the inanity of your remark, from anyone daring to judge others in a public scientific debate. Others can verify for themselves (at the above link) that I have uncovered the FACT that the RATIO OF TEMPERATURES in the atmospheres of Venus and Earth, over the range of Earth tropospheric pressures, is 1.176 (outside of the sulfuric acid cloud layer). That 1.176 ratio corresponds to an ABSORBED POWER ratio of 1.91 (not 1, or “even”, Mr. Pratt), which in fact is PRECISELY that expected from the ratio of the two planets’ distances from the Sun, and nothing else (1.176 = fourth-root of 1.91; temperature varies as the fourth-root of the absorbed incident power, got it?).

        Now listen closely, consensus defenders, because I know how the obvious facts go right over your heads (that includes you, Judith Curry–you have known of my analysis since early last December); I then wrote these fateful words: “This result also flies in the face of those [that includes you, Mr. Pratt] who would say the clouds of Venus reflect much of the incident solar energy, and that therefore it cannot get 1.91 times the power per unit area received by the Earth — the direct evidence presented here is that its atmosphere does, in fact, get that amount of power, remarkably closely.” Then, for the benefit of the lay reader, who would not be expected to understand the clear (to a competent physical scientist) implication of this simply-stated fact, I wrote: “This in fact indicates that the Venusian atmosphere is heated mainly by incident infrared [not the VISIBLE portion, which is indeed largely reflected, defenders, but INFRARED] radiation from the Sun, WHICH IS NOT REFLECTED BUT ABSORBED [or allowed in to heat the lower atmosphere] by Venus’s clouds, rather than by warming first of the planetary surface. (It also indicates that the Earth atmosphere is substantially warmed the same way, during daylight hours, by direct solar infrared irradiation…)” I urge the interested reader seeking the truth to study, not just my article, but the comments following, which go into these and other important corrections to current beliefs about atmospheric warming.

        When will a competent climate scientist appear, and show that he/she understands this elementary deduction, which I have already laid out for you? Let me lay out a further deduction for you “experts” who continue to thoughtlessly dismiss the definitive evidence, which is required to correct and advance climate science from this point on, and for the benefit of interested laypersons (and the all-capitals doesn’t imply yelling, just what I have learned is a necessary emphasis, to get you to focus upon the facts–YOU ARE INCREDIBLY STUPID, ALL OF YOU, AND YOU DO NOT DESERVE TO CALL YOURSELVES, OR BE EMPLOYED AS, SCIENTISTS, MUCH LESS EXPERTS. THE ANALYSIS I DID IS IN FACT UTTERLY CLEAR AND SIMPLE, AND SHOULD HAVE BEEN DONE BY CLIMATE SCIENTISTS 20 YEARS AGO, AND THE GREENHOUSE EFFECT DROPPED THEN. THAT IS HOW INCOMPETENT YOU ALL ARE. A WHOLE GENERATION HAS BEEN MISEDUCATED BY A PATENTLY FALSE HYPOTHESIS, as my Venus/Earth comparison proves.

      • YOU ARE INCREDIBLY STUPID, ALL OF YOU, AND YOU DO NOT DESERVE TO CALL YOURSELVES, OR BE EMPLOYED AS, SCIENTISTS, MUCH LESS EXPERTS.

        Thanks for the support, we need drill-sergeant motivation every once in a while.

        Why do you use the T^4 factor from the Stefan-Boltzmann equation when you evidently don’t believe in the overall statistical mechanics approach that scientists have been using all these years?

        Since radiation is on a continuum of wavelengths, how do you decide where to cut-off the infrared portion? Since you must believe in Stefan-Boltzmann, then you must integrate the energy density up to some IR cut-off. However since the Sun is so hot, most of the radiated energy is situated in the visible portion of the spectrum. So I can’t figure out how Venus gets enough energy to support that kind of temperature given that we artificially constrained the solar spectrum to only its infrared portion.

        Maybe, just maybe, you landed on a weird coincidence, and you are trying to contrive the rest of the parameters to fit this coincidence.

      • Odd that when you simplify Harry’s argument in order to make it more understandable, with the actual numbers in the two arguments being identical when you work them out, Harry can no longer recognize it as his own argument.

        It reminds me a little bit of the argument why one should obfuscate the version of a paper submitted for review and then if it’s accepted send the clear version. If you submit the clear version for review it will be rejected on the ground that the referees could easily have thought of that themselves. (The patent office gets that argument from wannabe infringers all the time.) Obfuscation forces the reviewers to work hard to verify its correctness, convincing them they couldn’t have come up with the result easily.

        The only downside of publishing the clear version is that some of the journal’s readership will complain that the referees aren’t paying attention and are accepting “obvious” stuff. (Damn, I could have invented NP-completeness, it’s obvious when presented clearly.)

        In this case the simplification doesn’t appear to have helped Harry, who can only recognize his argument the way he worked it out originally, the hard way, with a big table. And you’ll notice he continues to ignore the fact that Venus reflects 90% of the incident sunlight, claiming that’s irrelevant (though I’m not clear how he proves it’s irrelevant, that would seem very hard).

      • But the new Millenium started on 1 January 2001, and 2000 was the last year of the old one.

        Repeating this is good, as it rubs in the point that if moving a decade by one year can make such a difference then maybe one should be using a larger window.

      • Odd that when you simplify Harry’s argument in order to make it more understandable, with the actual numbers in the two arguments being identical when you work them out, Harry can no longer recognize it as his own argument.

        Vaughan, as an educator you are certainly aware of a corollary:
        It is always harder to evaluate a wildly incorrect solution to a homework problem than it is to grade something that another student has some sort of grasp on. In the former case, you often have to be a mind-reader.

      • Vaughan, as an educator you are certainly aware of a corollary:
        It is always harder to evaluate a wildly incorrect solution to a homework problem than it is to grade something that another student has some sort of grasp on. In the former case, you often have to be a mind-reader.

        WHT, this accurately characterizes teaching assistants, who are just getting started as educators. As you go from assistant to associate to full to chaired to emeritus professor, those “wildly incorrect” solutions that so intimidate teaching assistants gradually shrink with each successive decade of experience, until you can spot rubbish in your sleep and not even wake up in a cold sweat over it.

        When Alex Smith won Stephen Wolfram’s $25,000 prize with a 50-page paper a few years ago, someone asked me what I thought of the proof. I looked for the part that made the proof go through and it was obvious right away it was wrong. To this very day Wolfram acolytes continue to hound me on Wikipedia for saying so, but the absence of Smith’s paper from Wolfram’s Journal of Complex Systems, its only possible venue, tells a different story.

        As a student taking a mathematical logic course from Paul Eklof, I naively submitted what I thought was a clear solution to a homework problem about the finite intersection property or f.i.p. for (infinite) Boolean algebras. Because my solution didn’t use the method Paul had taught us (which I’d slept through since his lectures were kind of dull and I was a sleep-deprived hacker), the TA graded my answer as wrong. As a (very) naive student I would have accepted that judgement on the ground that evidently I’d overlooked some subtlety in Paul’s approach that was above my pay grade.

        Fortunately Paul was very conscientious and checked the work of his TA. (There were only about 15 students taking the class for credit, two of us were computer scientists and the rest were mathematicians.) To Paul it was obvious my answer was correct and he regraded it correct. I’d never seen a professor override a TA like that before and was amazed such a thing could even happen.

        That’s the difference between professors and TAs. If your TA grades you wrong and you don’t understand the objection, appeal to a higher court. I didn’t know this then, and if Paul hadn’t been so damned conscientious I would never have learned that lesson.

        No wonder Paul didn’t get tenure.

      • WHT, this accurately characterizes teaching assistants, who are just getting started as educators.

        You nailed me. In my academic career, I only made it to a laboratory TA, and did get burned out grading lab reports and trying to figure out who was making up data, using a wrong derivation, etc. Now that I know the secret, in retrospect I probably should have considered following your path :)

      • WHT, as a TA you might have appreciated TAing for me. For the 28 years of my teaching career at MIT and then Stanford, I always had the students grade the homeworks and the TAs help the students and keep an eye on the quality of the grading.

        Each week 10% of the class would find themselves at the business end of the teaching process, by either volunteering or being nominated to be the graders for that week’s three homework problems. Nomination was rarely needed since a stint at grading was mandatory and students preferred to get that duty out of the way sooner rather than later and would readily sign up each week for their turn.

        Student graders would be divided into three teams, one per problem. While the rest of the class was doing all three problems on their own without collaboration, each of the three teams would collaborate on getting the perfect answer to their assigned problem, with input from the TAs and me. Each team would write the perfect answer.

        When the homeworks were turned in, the perfect answers were distributed to the class, and each team set to work grading its problem, by now thoroughly steeped in every aspect of that problem after a week’s work on it.

        That week’s student graders were given full credit for the whole homework even though they’d skipped two out of three problems. This credit was only reduced when it was clear to everyone the student grader was not pulling his or her weight.

        If this cockamamie scheme had not worked I would have abandoned it as unworkable. However it worked remarkably well, certainly better than wearing out the TAs by making them do all the grading. (I did once try the latter system but the TAs seemed less happy.) The change of pace made it more fun (to the extent anyone could call homeworks “fun”), the division of labor scaled better, and all participants learned a wider variety of skills, including the TAs who in this way were elevated to middle managers (not that this met their parents’ expectations of a graduate education at MIT or Stanford).

        This system was my refinement of the system Albert Meyer was already using at MIT when he and Mike Fischer recommended to MIT’s EE department in 1972 that I be hired as a junior faculty member. I have described it from time to time to both MIT and Stanford faculty, but not a single professor (besides Albert as its inventor) has ever to my knowledge considered adopting it, perhaps because they couldn’t picture it working.

        But it did. I won’t claim it worked perfectly since in fairness its victims should be the ultimate judges of that, and every year had its share of a few students complaining about the system. However in those 28 years of using it both the students and the TAs generally took it in stride, if only because I told them that was how my classes worked. The anonymous end-of-year student evaluations gave me a fair sense of the happiness quotient with the system, and matters never got close to bringing complaints to anyone but me (since complaints to higher-ups would have just been passed back to me), let alone fomenting a riot.

        So all in all, 11 years after retirement and 8 years after giving up teaching for running a computer manufacturing company, in retrospect I (if not its victims) would have to judge this system a success overall.

        The other feature of my classes is that they were never graded on a curve. At the beginning of the term the thresholds needed for A, B, C, and D were stated and at all times everyone could see how they were progressing and estimate what grade they were likely to get based on the homeworks to date and the midterm once that was graded. The only adjustments I allowed myself were to the difficulty of the midterm, later homeworks, and final, based on the overall quality of the class, which could vary substantially from year to year. In this way I was able to maintain a fairly equal division between A’s, B’s, and C’s without grading on a curve. Comparisons between years may have been a tad unfair, but comparisons within a year were as promised at the outset.

        Further refinements of this approach are surely possible, but the system did have the undeniable benefit of scalability.

      • v. interesting, i’m emailing your grading idea to my faculty

      • As GIS has only global series,if we observe the southern Hemisphere the four decade trend,decreases in the 21st C which is consistent with surface actinometric stations .This is also consitent with theory that water vapour is schizophrenic ie it has both positive and negative feedbacks,suspicions are the late is dominant in the SH.

        http://www.woodfortrees.org/plot/hadcrut3sh/from:1970/mean:4/every:4/to:2010/plot/hadcrut3sh/from:1970/to:1980/trend/plot/hadcrut3sh/from:1980/to:1990/trend/plot/hadcrut3sh/from:1990/to:2000/trend/plot/hadcrut3sh/from:2000/to:2010/trend

      • Cute. I guess WoodForTrees is everyone’s playground now.

        I am unfamiliar with it. Could you plot year-on-year temperature change vs. CO2? The AGW hypothesis is that temperature change is a function of CO2; linear on the log of CO2.

      • I am unfamiliar with it. Could you plot year-on-year temperature change vs. CO2?

        Not with the interactive graph, but you can download the data and work it yourself.

      • Could you plot year-on-year temperature change vs. CO2?

        No. I use MATLAB/Octave, and Excel/CALC for that, each pairing being proprietary/open-source. MATLAB and Octave are more or less interchangeable, but I think it’s worthwhile avoiding features that work in one but not the other, especially since MATLAB has millions of users.

        Excel/CALC are good because MS Office is widely deployed and Open Office is a free download, and almost everyone else has or can easily download MS’s free Excel reader if they just want to look at other people’s work.

        MATLAB produces the nicest graphs if you use embedded postscript, but Excel reaches the largest audience when distributing stuff for examination (terrific for transparency, the whole world can see all the formulas and values creating the graphs, unlike GCM’s where the math is totally opaque, an intrinsic problem with GCM’s).

        I would say the question of how to “do it right” with such software is open. My presentation at the AGU meeting in SF on Dec. 8 gives a couple of ways of going about it, along with how the choice of way can influence the answers to questions like “How hot will it get by 2100?”, “Between years Y and Y’, how much of the temperature variation was our fault?”, “How should climate sensitivity be defined and what is its value with each definition?”, “How important is it to separate the various natural contributors to climate change?” (what difference does it make if they’re all lumped together) and so on.

        The answers depend on the method, suggesting that the questions can’t be answered precisely without a reason for preferring one method over another, which can quickly lead to arguments as we see here all the time.

        But the extent to which they depend is of interest, because questions for which the extent is small have more precise answers than those whose answers depend very heavily on the method.

      • Did you mean like this?

        I don’t know, what’s it mean? I know what the individual parts mean, what I’m missing is the big picture. What does it mean to juxtapose CO2 in parts per billion with the derivative of global 1960-now HADCRUT3 from 1960?

        I’m interested in analyzing global 1850-now HADCRUT3, in the literal sense of analysis as a sum of components, namely short term climate plus long term natural variations plus AGW, in order to better understand the relative proportions of each component and their significance if any. These are all temperatures, no mixing ratios. It would be terrific if WoodForTrees.org could perform that sort of analysis.

      • Paul, one feature that would add a lot to WFT would be a processing step that adds a different series to this series. The button would be labelled “Add series” and the parameter would be the series number. All series should be understood as padded with zeroes at each end when adding series covering different periods. Since each series can be scaled, including by negative numbers, this gives you the full power of a vector space.

        Here are some more suggestions in case any look worthwhile.

        A “Delay” button, which shifts the series to the right (left for negative delays).

        An “Expand” button which expands the time series by a factor, about its center say.

        A “Clip” button, since “From” and “To” seem to need to refer to the built-in time series.

        Exp and log would be useful operations. Exp in conjunction with add and scale then gives sinh, cosh, etc., while to multiply two series, take their log, add them, and exponentiate them. (But maybe less painful to have a “Multiply series” button analogous to “Add series.”)

        A “Year” button as a data source (under Test?) would give you essentially the line y = x. This would allow creation of one’s own time series, as a function of the year, using the other buttons. In combination with “Multiply series,” the Year button gives you monomials, which can then be scaled and added to get polynomials.

        Extension of scalar multiplication to complex scalars (notation: 3,5 or 3+i5) would automatically extend exp to produce cos (as the real part of exp(y * 0+iw) if y is the Year scaled by the imaginary number 0+iw where w is the angular frequency). A decaying cos would be had with -d+iw where the negative real d says how fast to decay, useful in modelling the decaying oscillations one sometimes sees in some temperature records.

    • Vaughan, with an increase of CO2 they expected a rise in temp. Compared to the data and models and the expectations, there is clearly seems to be a pause. Do you think there is no pause? Do you think the greenwire scientists are wrong about the pause too?

      • Vaughan, with an increase of CO2 they expected a rise in temp. Compared to the data and models and the expectations, there is clearly seems to be a pause.

        You know, it never occurred to me that people might be deliberately jerking me around. But after Baa Humbug’s post just now falsely accusing me of calling 9 years a decade when I’d been working with a genuine 10 years, and now this post from Kermit completely and totally and utterly ignoring the distinction I just drew between 2000-2010 and 1970-2010, suddenly the scales have fallen from my eyes.

        These bastards have been lying through their teeth all this time and I never realized it.

        What a fool I am. What a moron. A nincompoop. An idiot. An ignoramus. A schmuck.

        How could I have let them take me in like this? What was I thinking?

        They lie about expectations. They claim there is a pause when there is none. They say that a “decade” is 2001-2010 when that’s obviously nine years, not ten, and moreover nine years cherry-picked to hide the rise, easily done in such narrow windows (the more obvious nine-year period would be 2000-2009, if you see nothing wrong with picking 2001-2010 instead then I have shares in several Manhattan bridges for you). When you compare a real decade, 2000-2010, with their fake decade, you realize they’ve ripped you off by 12 months, cunningly removing the front end in order to hide the rise.

        Charlatans. Frauds. Cheats. Con men. Crooks. Deceivers. Shysters. Swindlers. Tricksters. Call the climate police. (Why am I getting a busy signal?)

        Ok, let’s consider this calmly. Although not everyone agrees that ten years is worth looking at (Ben Santer insists on a minimum of 17), let’s play along with those who think for whatever reason that ten years is reasonable.

        Now if we’re allowed to pick any ten year window whatsoever, say from March 1993 to February 2003, then there are a lot of windows that will show warming, and a lot that will show cooling. With that approach no one wins and no one is convinced.

        For the three centuries 1800 to 2100, I suggest that for those who believe ten years is sufficient to decide whether the temperature is going up, or going down, that we look at each of the 30 decades starting on January 1800 and ending on December 2099 (which is the last month of data woodfortrees.org gives you when you specify 2100 as the “To:” year, when the time comes, that is).

        What this means is that every “From:” or “To:” date that you type into woodfortrees.org, between 1800 and 2100 (looking to the future here), must be “congruent to zero mod ten” as they say in some academic circles, or a multiple of ten in others, or a year ending in 0 in yet others.

        I’m not trying to push this down anyone’s throat, I’m just bringing it up for suggestion. If you have a system that you believe is fairer, e.g. from and to the ides of March in years congruent to 7 mod 10, by all means bring it up for discussion.

        Ben Santer has already ruled himself out with his 17-year rule. This game is only for those wanting to bet on or otherwise point to ten-year windows.

        The ten-year-multiple rule is that all years must end in 0, with no fractions allowed.

        Who is for the ten-year-multiple rule, and why? Who is against, and why? Who doesn’t like ten years in the first place, and why?

        This will be an interesting test of whether the only unbigoted climate blog on the planet can agree on anything. If it can’t, the inevitable inference is too horrible to contemplate: every climate blog on the planet capable of forming a consensus is bigoted. (If you didn’t follow that logic you were asleep in logic class.)

      • why do you think they character attack Phil Jones and claim his HadCRUT3 work is untrustworthy and inferior to Spencer’s UAH, but then when they want to wheel out global cooling claims they use HadCRUT and go out their way to avoid using UAH?

      • Since WfT can fluctuate some month-to-month, I like the 120-month rule. Keeps one on the toes.

      • Yes, the Baa humbug exchange is probably worth bookmarking. Thanks for that.

        Why not randomly generate the start and stop points?

      • Why not randomly generate the start and stop points?

        Why not generate all pairs of start-stop points? It’s not as if there’s a lot of them, as I was trying to make clear at this comment.

        Once you’ve analyzed every pair, you can predict the distribution that a random generator of pairs will produce. In this case the number of pairs is only enough to distract for one second one computer out of a botnet of 100,000 computers blasting out Denial Of Service packets, before it rejoins its mates on the more important Task At Hand.

        Monte Carlo methods are only needed when there’s more data than you can completely analyze. This brings you into the long-running Bayesian-vs-frequentist debate, well represented in the statistics departments of both Stanford (Persi Diaconis etc.) and Berkeley (Michael Jackson etc.). Even though the machine learning contingent in my own department (Stanford CS) strongly represents the Bayesian outlook (Koller, Ng, etc.), my impression is that frequentists are gaining the upper hand in statistics departments. YMMV, as they say.

      • If you generated a uniform set of start and stop points corresponding to all possible pairs in the data set, you are getting close to generating an autocorrelation function. That can certainly pick out some periodicities.

      • Vaughan Pratt

        What a fool I am. What a moron. A nincompoop. An idiot. An ignoramus. A schmuck.

        The unexamined life is definitely the better one.

        I hate arbitrary rules.

        If you’re looking at spans of time shorter than Santer, ie below a 95% CI (which is dynamical, btw, so varies with dataset and with portion of the dataset — BEST is a great example, as 17 years is too little in 1800, and too much in 2000), then you _must_ evaluate all samples available within your larger dataset of the same length to develop context for the meaning of your sample.

        You _can_ work with ten year running lengths, if you have enough of them and treat them properly to purpose.

        There are statisical methods for calculating the CI of such treatments, and there are even valid reasons for doing so, if one intends to apply Bayesian analyses.

        For example, one could use Bayes’ Theorem to decide, given an observed ten year trend, what is the chance the 30 year trend has changed?

        Btw, one could similarly use Bayesian analyses to determine, given BEST and HADSST, what is the likelihood of various global trends; indeed, one needs only know BEST and the relative size of the part of the globe BEST covers, to give definitive answers about global temperatures using Bayes (improved considerably if one has meaningful information about land-sea temperature relationships).

        So it’s plain false to say BEST has nothing to say about global temperatures. Merely, one must use caution when discussing global temperatures using BEST only, or in combination with other data, to recall what BEST is and is not.

        And we’re onto something more interesting here..

        Every ocean sea surface dataset tells us the oceans are warming more slowly than the land, but are warming.

        What are the weather implications of warm oceans and much warmer (in places) land?

        Anyone?

        Anyone know what happens when the land is as cold as ever in some spots, really hot in other spots and the sea is pretty warm overall?

        Because that is the dominant trend that will determine the weather we pass on to our posterity.

      • You _can_ work with ten year running lengths, if you have enough of them and treat them properly to purpose.

        Quite right. Statistics is no longer used just for lying, it has long since branched out into many other areas. Carefully managed, modern statistics can support the truth every bit as effectively as the many alternatives.

        Had it not matured in this way, science and humanities departments more obsessively focused on what they considered to be “the truth” would never have allowed their university to found a statistics department liable to bear false witness against its neighboring departments at the drop of a pair of dice. All would have followed the lead of the physics department, quoting Einstein, “God does not play dice.”

        Thus is it said, all statisticians are atheists, and none are to be trusted.

      • Vaughan: This will be an interesting test of whether the only unbigoted climate blog on the planet can agree on anything. If it can’t, the inevitable inference is too horrible to contemplate: every climate blog on the planet capable of forming a consensus is bigoted. (If you didn’t follow that logic you were asleep in logic class.)

        That’s a good paragraph. I read the entire post. You know, …, sometimes it’s best to work out, chop down trees, weed your garden(*), or get down on your hands and knees and clean your wood floors with steel wool. You know, step out of the arena, clear your mind of words for a time.

        * Oddly, “seed your garden” means to plant seeds, whereas “weed your garden” means to remove the weeds. Maybe Kim can contribute something.

        Be of goodcheer,

        Matt

      • Carbon dioxide
        Has grown weeds in the Eden
        Of climate science.
        ===========

      • > This will be an interesting test of whether the only unbigoted climate blog on the planet can agree on anything.

        Vaughan, you seem to forget why God invented Dragonslayers.

        Go get these godcheerful bigots!

      • Hey, go easy on the accusations please.
        When I said there were 10 years in a decade not 11, I made (thanks to Woodfortrees clarification), what turns out to be a wrong assumption that 2010 ended at 31 december.

        My comment that we see what we want to see and hear what we want to hear was based on the graph i presented

        http://www.woodfortrees.org/plot/gistemp/from:1971/mean:4/every:4/to:2010/plot/gistemp/from:1971/to:1980/trend/plot/gistemp/from:1981/to:1990/trend/plot/gistemp/from:1991/to:2000/trend/plot/gistemp/from:2001/to:2010/trend

        which shows a flattening trend in the last quarter, though a steeper trend in the previous three quarters compared to the graph presented by Vaughan

        http://www.woodfortrees.org/plot/gistemp/from:1970/mean:4/every:4/to:2010/plot/gistemp/from:1970/to:1980/trend/plot/gistemp/from:1980/to:1990/trend/plot/gistemp/from:1990/to:2000/trend/plot/gistemp/from:2000/to:2010/trend

        Not in any of my past short exchanges with Vaughan have I purposely “jerked him around” or accused him of anything untoward. (though I may have used Aussie humour in some).

        Were you offended by my post Vaughan? If so, please accept my apologies, I wouldn’t have thought I had it in me to be able to offend you.

      • with an increase of CO2 they expected a rise in temp.

        Not monotonically year by year. They expected there to be decadal and even bidecadal flat periods. You can see this in IPCC model runs – 10 to 20 year flat or cooling periods, when the overall centennial run ended up warmer by the end.

        When it is said CO2 causes warming, that is not meant to imply that other factors suddenly cease. We still have a fluctuating sun, oscillating patterns in the climate system, volcanism etc. We will continue to get interannual/decadal variations on the long-term trend. Like the tide coming, each wave does not move further up the beach than the last. It is irregular, but eventually the tide comes in. That’s what ‘they expect.’

      • Vince whirlwind

        Thanks, Barry – do you reck on they’ll remember your lesson for the future?

  18. probably helps to take this little problem outside the realm of climate to get a better debate.

    Image if you will a beetle walking along a ruler and every couple of minutes you note how far a long it is, with the length along the ruler being given by the appropriate annual temp (say).

    Has the beetle “paused” over the last 20 mins (10 years)? Not really it is still moving but it hasn’t really made much progress further along the ruler.

    If you are a reflective type you might ask what’s going on?

    First observation is the local universe hasn’t changed much, same old beetle and ruler, no obvious macro impacts like a large foot etc etc.

    My point here is that in sense you can get a bit too clever – what’s going on might just be what beetles do around rulers.

    Second lets assume you are joined by another drunk and rather than bet on flies you decide to bet on which way the beetle will move next. This ups the stakes so you have to first agree some rules for sorting out who is going to win the bet (and probably agree the duration of the game because drunks have notoriously short attention spans).

    At this point the analysis of all things beetle gets serious and entomologist are called into advise – with deep arguments about whether it is relative heat, light, food or whatever that has been driving the poor thing along the ruler in the past, and whether this will continue. Or is the beetle in its death throws and about to explode.

    Even a statistician is summonsed who declares it simply looks like a random walk and has nothing to do with the environment, which advice the drunks find deeply satisfying as something close to their hearts.

    And the serious point is … well I’m not really sure there is a serious point to this question. Better to agree a criteria and wait the allotted time, leaving the entomologists to get on with studying beetles, and the statisticians and the drunks to their random walks.

  19. Someone has suggested yet another method for analyzing time series of land surface temperatures

    http://bishophill.squarespace.com/blog/2011/11/4/australian-temperatures.html

    I would be interested in comments from others here (c.f. the BEST data)

  20. Long term mean trend (over the past 160 years) is +0.05°C per decade

    Yet depending on the considered period one can notice that the trend may (roughly) vary between -0.07°C per decade (as observed between 1880 and 1910) and + 0.17°C per decade (as observed between 1970 and 2000).
    Look there

    Thus one can state that trend = 0.05 +/- 0.12°C per decade.

    Since [CO2] has steadily increased over these 160 years, this scattering of +/- 0.12°C per decade can only results from natural variability (alone), whereas the back-ground trend of + 0.05°C per decade COULD POTENTIALLY be attributed to anthropogenic forcing.

    BUT if Mother Nature is powerful enough to explain a variability of +/- 0.12°C per decade, why couldn’t she also explain the much smaller background trend of + 0.05°C per decade ?

    It seems for instance there is a 1 Kyear natural cycle leading to RWP about 2 Kyears ago and a MWP about 1 Kyear ago… See for illustration Ljungqvist 2010
    Actually Global Warming observed during 19th and 20th centuries is very likely corresponding to LIA recovery, i.e. from the cool period of this 1 Kyear cycle.

    • I agree Eric.

      No change in the global mean temperature pattern since record begun 180 years ago as shown in the following graph:

      http://bit.ly/sKUfTx

      • Girma’s “following graph” shows a steady rise. I guess what Girma means is that the slope (aka derivative) isn’t changing. Temperature is rising inexorably.

        Since it’s been rising for so long (180 years, my god), it looks like it’s going to keep rising for ever. We’ll be dead of old age by then, but at that rate our grandchildren will be dead from the heat. Which kind of death is worse, would you say, Girma?

      • Vaughn

        The warming rate has not changed. The steady warming started 160 years ago, not mid-20th century!

        Do we know what pushed the global mean temperature in this 0.06 deg C per decade warming trajectory before 160 years ago? Do you think something that was constant for 16 decades will change in the next decade? IPCC projection of about 0.2 deg C per decade violates this historical temperature pattern.

      • Actually, Girma, I do suspect that whatever caused the steady warming for a century and a half has changed, and it’s the grin of the Cheshire Cat that tips me off.
        ================

      • “Emissions have accelerated for sure but they never reached an exponential growth situation.”

        There is no difference between accelerated and exponential growth- mathematically they are the same.

      • There is no difference between accelerated and exponential growth- mathematically they are the same.

        Acceleration due to gravity (growth in speed) is not exponential. Mathematically they are completely different.

        Another guy that didn’t take high-school physics, yet thinks that he can
        debunk AGW, yawn.

      • “Acceleration due to gravity (growth in speed) is not exponential. Mathematically they are completely different. ”

        Earth gravity: 9.80665 m/s^2

      • gbaikie wrote,

        Earth gravity: 9.80665 m/s^2

        At least you can get that much right

        With acceleration due to gravity, velocity will increase
        g * time

        if hypothetically, gravity had an exponential (or compounding) growth effect then
        v0 * exp(k*time)

        Do you understand this?

      • “if hypothetically, gravity had an exponential (or compounding) growth effect then
        v0 * exp(k*time)
        Do you understand this?”
        You talking about Exponential growth- as in a chain reaction
        But this started from “exponentially increased”
        I assumed you using increased and growth as though they were synonymous.
        As one gets closer to a gravitation well one would have increased gravitational acceleration. E.g. At certain distance from earth acceleration could 1 m/s/s, and as you get closer it could become 2 m/s/s, and 4 m/s/s, and with earth, 8 m/s/s would be highest it could get. As far as I know such accelerated increase is not normally considered significant but one could probably achieve this depending on starting velocity and whatever gravitational body is selected. It also seems possible to have an even higher growth than Exponential Growth in regards to gravity. And if this isn’t the case maybe that would tell something about gravity- or not and it would be simply be curious fact.

      • I assumed you using increased and growth as though they were synonymous.

        Well nice try in trying to extricate yourself from your statements. I showed that energy use has not been exponential and that is how this discussion started.

      • Dr Pratt,

        Human emissions of GHG have exponentially increased over the past 150 years.
        According to AGW theory and IPCC claims, warming should be steadily accelerating…
        Actually this is formally falsified by observations showing quite a constant back-ground trend of +0.05°C per decade, on top of which cooling and warming periods are alternating.
        This results in an overall rate of temperature change of 0.05 +/- 0.12°C per decade.

        Indeed :
        - Absence of accelerating warming
        - Existence of 30 years long cooling periods [1880 - 1910] then [1940 to 1970]
        - Similitude of warming rates (about +0,15°C per decade) during both [1910 - 1940] & [1970 to 2000] periods, whereas anthropogenic CO2 emissions have been multiplied by 5 here between,
        formally disproved AGW theory and IPCC claims.

      • Human emissions of GHG have exponentially increased over the past 150 years.

        Not true you liar! Emissions have accelerated for sure but they never reached an exponential growth situation. I know because I actually lifted a finger and plotted the data, not just making up stuff like you are doing.

      • Just on a point of information: ‘exponential growth’ means that the rate of increase is proportional to total size.

        So, anything that is rising at a certain percentage is exponential growth. Exponential growth can be characterised by a doubling time as well as a percentage increase over a certain time period. To calculate this just divide the percentage increase into 70.

        For example: an annual increase in, say, prices of 7% will mean they will double every 10 years.

      • @WHT: Emissions have accelerated for sure but they never reached an exponential growth situation.

        WHT, let’s take 2.2% as the CAGR for anthropogenic CO2 since 1800. CAGR (compound annual growth rate) means exponential. What precisely is your evidence to the contrary? Don’t forget to subtract the conventionally accepted natural background level of 280 ppmv before doing that arithmetic.

      • WHT, let’s take 2.2% as the CAGR for anthropogenic CO2 since 1800. CAGR (compound annual growth rate) means exponential. What precisely is your evidence to the contrary?

        My evidence is that you can plot the data from the CO2 Analysis Center on a semi-log graph scale and the curve is concave down, especially in recent years. This means whatever exponential growth existed has stopped. The way to think about it is that an exponential function when expanded in a Taylor’s series has all these higher order power terms. For fossil fuel production it looks like the series stalled at Time^4, or the 4th power term in the series.
        You can see this in this curve, where I started a power-law growth function from the year 1800:

        If this was an exponential, it would be rocketing upward at the current date.

        This is not a big deal, just that the various energy crises and oil shocks we have had over the years have slowed down the exponential growth in the production of oil. Coal has never been exponential. Natural gas is too early to tell.

        I have been using the power law function for my oil production modeling for several years now (this was in 2006 from this page http://mobjectivist.blogspot.com/2006/01/would-you-believe.html)

        One of the early curves I fit was to Wikiword growth and I spotted a power-law of 2.

        I just did it again against the Wiki stats, and this is what it looks like now five years later:

  21. All warming in the late 20th century between 1996 and 1998. QED.

    • Heh; I guess the CO2 saved up its 20thC kick for the last possible moment, and then laid it all on! Or maybe all that back-radiation was just banging around before settling down as actual heat. Or …

  22. Judith Curry:

    The “question of the week” was: what’s your scientific basis for your own claims?

    You said “Our data show the pause.” That means the Berkeley data. You didn’t say “maybe.”

    You used that claim to accuse Richard Muller of “hiding the decline” — to a reporter from the Daily Mail. You also said “There is no scientific basis for saying that warming hasn’t stopped.” The implication is clear, that if Richard Muller makes a claim about temperature trend you insist he have a scientific basis for it. So when you made a claim about temperature trend in the Berkeley data I asked you for your scientific basis.

    Apparently you don’t have one.

    • Apparently you are clueless…

      no warming since 1998 indicates the “perceived pause”. note i said perceived. in some of the other data sets it actually shows decline. but that time series is to small to determine anything.. Some of the faithful warmers seem to think that this is a gotcha moment when there is no factual basis for believing the long term trend (10,000 years PLUS) has ended.

      In fact that same data shows were within natural variation.

      I wonder if you will proved the documentation of hypothesis falsification for CO2 being the ONLY way the earth can be warming… . we all know that the science HAS NOT BEEN DONE..!

      Interesting you want EVIDENCE but you fail to show your own? Hmmmmmm

      • Do you mean “perceived” as in reading tea leaves?

        The warming (as degrees/year) is not perceptibly lower after 1998 than in the 20 years preceeding 1998. In fact, by the BEST data, it is numerically higher.

        wget http://www.berkeleyearth.org/downloads/analysis-data.zip

        unzip analysis-data.zip

        In R:

        x=read.table(
        “~/Downloads/analysis-data/Full_Database_Average_summary.txt”,
        comment=’%’,
        col.names=c(“year”,”anomaly”,”uncert”,”anom5yr”,”unc5yr”))

        > coef(lm(anomaly ~ year, x))
        (Intercept) year
        -11.347565279 0.005880988
        > coef(lm(anomaly ~ year, x,subset=year>=1998))
        (Intercept) year
        -47.17089044 0.02398252
        > coef(lm(anomaly ~ year, x,subset=year coef(lm(anomaly ~ year, x,subset=(year1977)))
        (Intercept) year
        -41.79133158 0.02121579
        >

      • Unmunge some symbols:

        > coef(lm(anomaly ~ year, x,subset=(year<1998 & year >1977)))

      • Apparently you are clueless…

        This struck such a resonant chord within me that I felt no need to read further.

        Had you said “Apparently you a genius,” I would have been motivated to read further in order to locate the precise error in your argument.

    • ?

      In the article she sounded more like she was distancing herself from BEST, so why would she call it “Our data”? She was upfront about her limited role in the BEST study and I would expect she would probably refer to it as “their data” if she meant only BEST’s data.

    • Bill H,
      You need to do a bit better than just call Tamino clueless. Rational argument could be used to show Tamino is possibly incorrect in his argument, but that would require a high degree of understanding on your part which you probably don’t possess.

      • Rational argument could be used to show Tamino is possibly incorrect in his argument, but that would require a high degree of understanding on your part which you probably don’t possess.

        Oh come on, even in 300 BC people could follow Aristotle’s argument that all statisticians are liars, Tamino is a statistician, therefore Tamino is a liar. You’re proposing to trust a self-confessed liar?

      • There wasa nice statement in Zalapin and Ghil 2011 to Roe baker 11

        Fitting a distribution is very different from finding physical
        reasons for it. Accordingly, the observation that the
        linear model in Fig. 1 of RB07 fits the distribution of
        climate sensitivity from climateprediction.net may be a
        neat statistical fact but its relationship to the physics of
        climate change, if any, has still to be explained.

        From a deeper perspective Nalimov (Komolgorov assistant director and Gnedenko’s conscience) said

        One of the principal scientific tasks is to explain observational results according to the underlying factors (or mechanisms). The vast data accumulated up to the present show that this task in its general formulation cannot be unambiguously fulfilled either by the methods of “numerical spectroscopy” or by those of “logical spectroscopy.” Computers have only made the task more difficult. But now a new way seems to emerge: reducing information by means of unfolding it, i.e., presenting it through a set of models. However, this may be another illusion.

        …From a general methodological standpoint, the following feature is important to emphasize: the’ language of mathematics, for the first time, is allowed to unify different biological trends, and this has happened without a generally novel or profound understanding of ecology. Mathematics was used not to reduce complexity but to give a detailed, immediate description. This is a new tendency in science. But where will it lead? The time is not yet ripe for a final conclusion, but scepticism is quite in order.

  23. In today’s news, the year 2010 has seen a 6% increase in CO2 from 2009. Given that the trace gas radiative transfer model describes photons moving at near the speed of light, shouldn’t we have seen a 6% increase in global temperatures? if not, why not? Given that global economic activity, primarily in developing nations, has continued to increase, and presumably the CO2 emissions that accompany increased global economic activity have increased, has the global temperatures increased yet again another say 6%. If not, why not? Is some process, man made or natural overwhelming the trace gas radiative transfer model behavior, and what is it? Is there a hiatus in global temperature escalation? Is there science vs speculation for such a slowdown in rate of temperature rise? In this vein, I think of compound interest and its multiplicative effect on money held for a long time. Not seeing an ever escalating global temperature; i.e., compounded upon itself, year after year after year, maybe this whole CO2 focus is silly. Maybe there are a lot of other players in this sandbox and escalating CO2 speculations need to step aside and wait for the other players to have their say. Since CO2 escalation is not a one to one connection with escalating global temperatures, maybe CO2 needs to step outside of the sandbox altogether. I suggest, governments redirect our resources to something a little more likely to be true.

    • Do you have a link for that? First it seems like last years news, and 6% is probably not the increase in the total. The total increase is about 1% a year or less from what I recall.

      • 0.68 % rise…
        for all intents and purposes .7

        me thinks that a decimal has hopped around….

      • Oh, it’s something about the CO2 output not the ppms measured in the atmosphere.

      • Associate Press: Seth Borenstein 11-04-11
        U.S. Department of Energy calculated global output of heat-trapping carbon dioxide. Comments from MIT’s John Reilly; “monster increase that is unheard of” Gregg Maryland at Applachian State University; Its a big jump says Tom Boden Oak Ridge National Laboratory. Latest figures put global emissions higher than worst-case projections from IPCC. Forecast for 7.5 degrees Fahrenheit as best estimate. Reilly from MIT states that scientists have generally found IPCC predictions too conservative.

      • Ever so slyly
        What got to John Reilly?
        ========

    • In today’s news, the year 2010 has seen a 6% increase in CO2 from 2009.

      Now the narrow-window shoe is on the other foot. Skeptics have been inferring global cooling from a mere 10 years of temperature data, for which they been rightly taken to task. Now believers are inferring a sudden change of circumstances from a mere comparison of two consecutive years! If justice is to be served, the same criticism must be made of the believers.

      The following table, based on data that can be found here and here, paints a very different picture. It gives the Compound Annual Growth Rate, or CAGR, of CO2 emissions for fossil fuels (solid, liquid, and gas), flaring (in oil fields and refineries), and cement production emissions, for all 55 possible intervals in the period 2000-2010. The longest interval, 2000-2010, is the 3.08% figure at the upper left, the 10 one-year intervals are on the diagonal at lower right. The one-year interval that’s been hitting the news today is the 2009-2010 interval at lower left, showing 5.95%.

      000 2010 200920082007200620052004200320022001
      2000 3.08 2.76 3.30 3.42 3.61 3.68 3.62 3.10 1.70 2.46
      2001 3.15 2.80 3.42 3.58 3.84 3.98 4.01 3.42 0.94
      2002 3.42 3.07 3.83 4.12 4.58 5.02 5.58 5.96
      2003 3.07 2.59 3.41 3.67 4.12 4.55 5.20
      2004 2.72 2.08 2.97 3.16 3.59 3.91
      2005 2.48 1.63 2.66 2.79 3.26
      2006 2.28 1.09 2.36 2.31
      2007 2.27 0.48 2.41
      2008 2.2 -1.41
      2009 5.95

      The first thing to notice is the huge difference between the interval 2008-2010 (2.2%) and 2009-2010 (5.95%). This difference can be attributed to the fact that CO2 emissions declined by 1.41% in 2009 (the one-year 2008-2009 interval).

      Now work up that column to progressively earlier starting years. Notice that there is no interval ending in 2010 bigger than 3.42%, with the exception of the one-year interval 2009-2010, which is almost double 2002-2010, and double or more all of the other CAGR’s for intervals ending in 2010.

      Now look at the one-year interval 2002-2003. In 2003 CO2 emissions rose 5.96% over 2002. That’s even bigger (by a very tiny amount) than the 5.95% that’s got everybody running around in circles. Why didn’t that big jump bother everyone back then?

      And look at all 9 of the two-year intervals (the diagonal that starts at 2.2% at lower left and runs up to 1.70% at upper right). The biggest two-year interval is 5.58% for 2002-2004. The two two-year intervals closest to the present are 2.2% and 0.48%. Pikers!

      The much bigger picture is that the anthropogenic component of the CO2 level, namely the Keeling curve minus 280 ppmv, has been growing at a remarkably steady CAGR of almost exactly 2.2% for the past 53 years! This one-year blip is not a new phenomenon, contrary to what some hysterical alarmists have been saying (witness the short intervals starting in 2002), and will have no perceptible impact on the CAGR of the Keeling curve. It is climbing at a well-known pace.

      Yes we should be hysterical about that pace. No we should not be even more hysterical this year than last. Even though 2009 declined 1.41% over 2008, we should have been equally hysterical back then.

      Going back an additional 150 years, this graph shows the annual growth rate (AGR, i.e. CAGR exclusively for one-year intervals, no need for compounding) in CO2 emissions from the same types of fossil fuel (including oil field and refinery flares and cement production), for every year from 1850 to 2008. The CO2 emissions can be seen hovering around 5% during the 19th and early 20th century, with a spike to 17% in 1854 and seven 9-12% spikes between 1872 and 1907. It then declined to an average AGR of 1.7% between the two world wars, with huge declines of −14% in 1919 and 1921 offset by 15% spikes upwards in 1920 and 1923, and with the 1930-1932 depression each declining by 10% in three successive years (so a −30% decline for the three years combined).

      The AGR then rebounded before and during WW2 but fell to −16% near the end of WW2, rebounding again postwar to an average of 4% during 1950-1980, then dropping to an average of 1.2% during 1980-2000, bring us up to the present decade treated more exhaustively above. (Well, I’m exhausted anyway.)

      • Vaughan Pratt – the link in this sentence is not working:

        Going back an additional 150 years, this graph shows the annual growth rate (AGR, i.e. CAGR exclusively for one-year intervals, no need for compounding)

      • Having trouble finding any problem. What’s the error message, and is anyone else having any trouble seeing this graph?

      • Meanwhile I realized what was broken with the URL for the 1850-2008 graph: I’d left off “.stanford.edu” which is ok on my machine but not elsewhere. Here it is both ways, clickable and copyable:
        http://boole.stanford.edu/LGW/CAGRfuel.jpg

        While I’m at it, let me format the table a bit better, using the pre tag. (Not sure how WordPress handles line overflows with pre.)

        ALL 55 CO2 EMISSION CAGR's FOR 2000-2010
        +----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
        |Fm\To 2010| 2009| 2008| 2007| 2006| 2005| 2004| 2003| 2002| 2001|
        |----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
        |2000| 3.08| 2.76| 3.30| 3.42| 3.61| 3.68| 3.62| 3.10| 1.70| 2.46|
        |----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
        |2001| 3.15| 2.80| 3.42| 3.58| 3.84| 3.98| 4.01| 3.42| 0.94|
        |----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
        |2002| 3.42| 3.07| 3.83| 4.12| 4.58| 5.02| 5.58| 5.96|
        |----+-----+-----+-----+-----+-----+-----+-----+-----+
        |2003| 3.07| 2.59| 3.41| 3.67| 4.12| 4.55| 5.20|
        |----+-----+-----+-----+-----+-----+-----+----+
        |2004| 2.72| 2.08| 2.97| 3.16| 3.59| 3.91|
        |----+-----+-----+-----+-----+-----+-----+
        |2005| 2.48| 1.63| 2.66| 2.79| 3.26|
        |----+-----+-----+-----+-----+-----+
        |2006| 2.28| 1.09| 2.36| 2.31|
        |----+-----+-----+-----+-----+
        |2007| 2.27| 0.48| 2.41|
        |----+-----+-----+-----+
        |2008| 2.20|-1.41|
        |----+-----+-----+
        |2009| 5.95|
        +----+-----+
        
      • Incidentally a point about how to combine CAGR’s. Since 2010 was 5.95% and 2009 was -1.41%, it’s tempting to take their arithmetic mean, namely (5.95 − 1.41)/2 = 2.27.

        But that’s not how compounding works: the growth is geometric, not arithmetic. In this we’re dealing with consecutive factors of 1 − .0141 = .9859 and 1 + .0595 = 1.0595. The CAGR of any two consecutive periods of the same duration is their geometric mean, which in this case is sqrt(.9859 * 1.0595) = 1.02204 or 2.20%.

        Not a lot less, but it does answer the question of why the table gives 2.20% if you’d been expecting 2.27%.

        And since this is a climate blog, where doubling time is (or should be) on everyone’s mind, it’s worth knowing the rule that when the CAGR, expressed as a percentage p%, when p is at most 4% the doubling time is 70/p years (add a few months when p is between 5 and 10).

        So if the CAGR of emissions over a few years seems to be averaging 3%, it should take 70/3 = 23.3 years for the annual CO2 emissions to double.

        Likewise if the anthropogenic component of atmospheric CO2 (the Keeling curve minus 280) has been growing at a steady 2.2% per year over the 53 years since it started taking measurements, the doubling time is just a tad over 70/2.2 = 31.8 years, actually 31.852 years if you do it the hard way as log(2)/log(1.022) (any base of log).

        (In poster session 5 (1/14/09) of the 89th American Meteorological Society Annual Meeting, David Hofmann mentions both 30 and 35 years in his poster and then at the bottom of the extended abstract (see link near bottom of Hofmann’s poster) uses their arithmetic mean, 32.5 years, pretty close to the 31.8 years obtained by more careful fitting.)

      • (Not sure how WordPress handles line overflows with pre.)

        Turns out whatever WP is doing is browser-dependent. Firefox displays my pre-tagged table just fine, with it jutting out to the right of the column, while Internet Explorer and Chrome wrap it unreadably. But one can use the mouse to copy it from either of the latter two browsers and paste it into anything (Word etc.) and it displays just fine. Go figure. Next time I have a table I’ll try formatting it with latex (which works nicely on WordPress except for the antialiasing making it unreadably light grey).

    • “In today’s news, the year 2010 has seen a 6% increase in CO2 from 2009. Given that the trace gas radiative transfer model describes photons moving at near the speed of light, shouldn’t we have seen a 6% increase in global temperatures? if not, why not?”

      CO2 increases on average about 2 ppm per year. But this is an average, it bounces around each year- e.g it could be a 1.76 or 3.2 ppm increase in one year.
      It seems rather silly to state this as news.
      But maybe they meant 6% of 389 ppm [rather rate of increase]. That would be “breaking news” but far as I know it hasn’t happened.

      I think reporting normal events as though they are unexpected or unusual is
      an common disinformation tactic- that or reporter needs to make a living.

  24. I came to see a menagerie of Warmista. Seems none admit to it any longer.

    • Jes us ice bears here, chillin’.
      ==============

    • Theo Goodwin.

      I note that you have been using, for a long time on many internet fora, the term “Warmista” as a plural form.

      It seems that you might be trying a little too hard to appear intellectual, because most a-suffixed plurals are um-suffixed singulars (e.g. datum -> data) which would make the singular of your pet term a “warmistum”. Given that the word appears to have the same fancied root as others such as “barista” or “Sandinista“, I would suggest that your pretense to linguistic intellectualism is slightly misplaced.

      Frankly, you should stick with “warmistas”, just as “baristas” and “Sandinistas” are the accepted English plurals. If you really want a poncy plural for more than one “warmista” perhaps you might consider “warmisti” or “warmistæ”.

      Just sayin’.

      • No one counts the spots on a speckled puppy.

      • …or the errors made by those who practise denialism…

      • I count the number of times people change their mind. Some people take “flip-flopping” as a sign of feeble-mindedness. But when a person can respond to new information and adapt accordingly, it seems to me that they’re better equipped mentally to cope with today’s rapidly changing world, not just climate change but also its tumbling economy and crushing unemployment.

        Bernard J., you seem to have some experience with Theo Goodwin, where would you place him on that spectrum?

  25. My main question here is “so what?”. I do wonder why the climate establishment is so worried and is rushing to try to explain why there has been a pause. This is a very telling statement about how they do science and how political agendas can influence their scientific objectivity. Whether or not there is a pause seems to me to be a very minor point in the grand scheme of things. What I do think is more interesting is that none of the catastrophes or more alarmist predictions have taken place or seem to be imminent. I am reminded of Lindzen’s point that focusing on global mean temperature anomaly, which is a peculiar statistical residue, actually prevents us from understanding the climate better. You know for most of the world’s people, life has gotten a lot better since 1970 and a lot of that is due to the exploitation of fossil fuels.

    • Really nice comment; couldn’t agree more. The reaction to such a minor (perceived) pause speaks volumes about the political pollution of the science. And where are all the catastrophes? No doubt we will hear all about them in the next 3 weeks.
      /cynicism off

  26. In assessing recent global temperature trajectories, two curves are worth keeping in mind. The first is the observed twentieth century global temperature curve (including the years through 2010). The second is a GFDL-model simulation that compares the curve projected from changes in greenhouse gases.

    What stands out to me about the first is that the temperature was clearly on an upward trajectory, but that the trajectory was one punctuated by peaks and dips along the way. An observer with no previous awareness of issues surrounding recent temperature would probably not single out the past decade as particularly unusual, nor indicative of a significant departure from previous climate behavior.

    This of course does not tell us why dips or flat intervals occurred in the past. It is easy but somewhat speculative to invoke combinations of solar changes, aerosols (anthropogenic and volcanic), and internal climate modes to explain the deviations from a smoothly rising curve, and there are ample data to indicate these played a role. However, if we look at the second curve, a couple of interesting observations stand out. The first is that ghgs are very likely to have contributed to early twentieth century warming, although their fractional role was smaller than after mid-century.
    The second and more interesting (to me) observation is that the simulated temperature changes are punctuated by multiple short term peaks and dips, differing from one model run to another, although the climate variables mentioned above were omitted from the simulations – there were no changes in model input in solar or aerosol forcing, and ENSO was largely eliminated by smoothing. These short term fluctuations therefore appear to reflect mainly the chaotic element in a climate forced exclusively with ghgs. (The simulated warming exceeded observed warming, and a role for aerosol cooling in that disparity was suggested, but the evidence for its magnitude was not discussed and has been a topic elsewhere).

    In evaluating what is happening currently, it is reasonable to bring solar, aerosol, and internal mode factors back into the picture, but it would not be too surprising to find that they are not needed to explain every short term fluctuation in the temperature record.

    • The Hadcrut 3 curve shows more recent flatness in the smoothed data due to the higher value it assigns to 1998. The unsmoothed annual up and down variations don’t demonstrate much difference between the Hadcrut and GISS curves over the course of the rising temperatures shown since 1910, and are prominent throughout both records.

      • The oceanic oscillations dominated the 20th Century with a spotted sun dogging them, and driving them; if this new variability of the sunspots presage global cooling, as it did in the Maunder, we may cool for a century or more.

        Possible, then, that we may tease out the pusillanimous warming effect of CO2.
        ==============

      • Kim – We know the oceanic oscillations played a very minor role at most in the net warming after mid-century. Because we have less information on ocean heat content changes earlier than that, we can’t accurately assess their role in the first half, but the known forcings in combination were probably fairly similar in magnitude in both intervals, and so the unforced oscillations probably played a relatively small net role then, even if we can’t be sure. At shorter than half century intervals, their role may have been larger at various times.

      • Second try at a response –

        Kim – We know the oceanic oscillations played a very minor role at most in the net warming after mid-century. Because we have less information on ocean heat content changes earlier than that, we can’t accurately assess their role in the first half, but the known forcings in combination were probably fairly similar in magnitude in both intervals, and so the unforced oscillations probably played a relatively small net role then, even if we can’t be sure. At shorter than half century intervals, their role may have been larger at various times.

      • You’ve a lot of ‘hope’ in there, Fred, with which to confirm your bias, manifest in our ignorance. The sun’s action on climate is not understood, and notwithstanding Bart R’s objections above, the sun does not act by magic. It only seems that way in our ignorance.

        What causes the millenial scale climate variations shown by the Minoan, the Roman and the Medieval Warm Period, and the intervening coolings. What caused the century and a half 0.06 degrees C/decade temperature rise since the Little Ice Age? What caused the large, sparse, and primarily southern hemispheric sunspots during the Maunder Minimum?

        Inquiring minds want to know, and policymakers need to know.
        ================

      • kim

        Inquiring minds want to know; biased minds want to know only what agrees with their preconceived notions, and will reach for any needlessly complicated contrived assumption to support them.

        Policymakers, also, you must not have met very often.

        Most or all often make policy in ignorance, and make the right call given the state of knowledge of their time.

        Policymakers guided by false ‘knowledge’ (let’s call it Knowledge Intentionally Made-up, or ‘kim’ for short), however, cannot make the right call.

        If you insert such ‘kim’ into policymaking, you hurt real people with real bad policy.

        Like magic sunspot motion at a distance, unproven regional effect TLA’s we only have some shakey monastic scribbles in Latin to support (at a time when monks were renowned to lie in their reports to try to obtain recruits or patrons).

        What year did your LIA end, kim? I’ve found no less than forty candidates for the end of the LIA in literature, some of them _before_ the start date of other reported LIA spans, some of them well into the period of BEST data — which data contradicts those LIA endpoint claims.

        If you can’t even say when your LIA was, how can you claim you know its amplitude so reliably as to have three, or even two, decimal points of precision?

        While sunspots are fun and pretty, they’ve demonstrated remarkable variability in period, ‘submerged’ in some hypotheses so their disappearance isn’t real (which must mean their appearance is less reliable too, if there could have been many submerged invisible sunspots lurking, all counts of visible sunspots are less meaningful), and really poor correlation to Earth temperatures except for one or two isolated and possibly coincidental periods.

        While you might have something in your spotty theory, it’s just more kim without evidence, and neither have all efforts to date to manufacture evidence to support the preconceived notion nor genuine work to collect enough evidence to get a clear picture of what may be actually happening have produced satisfactory levels of confidence.. and even then, for all that, we’re still able to make some fairly confident claims about what sunspots aren’t doing.

        They aren’t doing what we’re observing dominantly in the century-scale global temperature change.

        All the kim fables stitched together don’t change that.

      • The sunspots are merely disappearing from our visible spectrum, the dynamic areas persist. I think they disappear from a cause also causal to Maunder like global cooling, and I grant that I am speculating.

        It’s kind of pitiful that you source millenial scale climate variation to monastic scribbles. You are paying too much attention to the monkish cartoon scribbles of Trenberth, and not enough to historical evidence of constant climate change.
        ================

      • kim

        You’re pinning your hopes on the horns of a dilemma of your own making.

        The sunspots are merely disappearing from our visible spectrum, the dynamic areas persist. I think they disappear from a cause also causal to Maunder like global cooling, and I grant that I am speculating.

        If you have an instrumental way to demonstrate this “disappearing from our visible spectrum” hypothesis, then all sunspot observations prior to the date that instrument began measuring must be all but thrown out, because we would have no clue what invisible priors existed, so the uncertainty of the pre-instrumental record would skyrocket.

        If you don’t have any way of detecting these invisible ghost spots, then, well, that speaks for itself.

        And I’m not accusing the Sun of acting by magic, kim. I’m observing you partake of magickal reasoning, a form of irrationality. As such, you will often find yourself dismissed by rational people in logical discourse, and likely won’t even have any idea of why.

        It’s kind of pitiful that you source millenial scale climate variation to monastic scribbles. You are paying too much attention to the monkish cartoon scribbles of Trenberth, and not enough to historical evidence of constant climate change.

        I’m afraid I don’t know Trenberth, so cannot comment on that comparison. However, on the history of monks, I’m fairly well-read. They’re by and large audacious liars, unreliable in almost every detail in their wishful records and manipulative correspondences.

        Please, by all means name your first hand historical evidence. Is it written? In Latin? Old High Frisian? One of the Slavic or Baltic languages? I’m good with those. Provide your sources and your cites, to allow me to evaluate this historical record of yours more closely, as I admit there is far more record out there than I have yet examined, and I’d love it if any of it amounted to half of one percent as meaningful as even the worst weather station used in the most shoddy of the modern datasets.

        Name it. Link it, if you can.

      • Yes, the dynamic areas are still there, observable instrumentally. Presumably, given the fusion dynamo, TSI remains approximately the same during these episodes of Cheshire Cat sunspots. If the Maunder cooling is from the same cause as the change in the sunspots, I have no dilemma. Please explain large, sparse, and predominantly Southern Hemispheric sunspots in the Maunder. Why the hemispheric asymmetry?

        So, ignore history if you please. Please explain the Minoan, the Roman, and the Medieval Warm Periods and the intervening cold spells from ice core data.
        =============

      • kim

        Do you perchance refer to http://science.nasa.gov/science-news/science-at-nasa/2009/03sep_sunspots/ or the like?

        It appears your reading of the topic is filtered through WUWTism, which would account for the skewness, as what you say does not match the original scholarship on the matter.

        Could you provide references to original scholarship on Minoan, the Roman, and the Medieval Warm Periods and the intervening cold spells from ice core data if you would, with commentary on how to determine amplitude of temperature shifts from paleoclimatology, start and end dates and how you determine them, and of course, how to resolve which of the ice cores do and do not have corresponding indicators for such events? My readings on the matter are sparse, but I’d understood agreement was poor, resolution of date somewhat poor, and amplitude indeterminable. I’d love to be corrected by learned dissertations.

      • No one knows the implications of the disappearing sunspots. I suggest that since the last time they disappeared the world got cold then this time they disappear the world might get cold. Simples.

        How foolish of you to deny millenial scale climate change. Are you a devotee of the Piltdown Mann?
        ===============

      • Judy, please consider discussing the findings of Livingston and Penn. I, for one, would certainly like more discussion of the somewhat ambiguous isotope record during the Grand Minimums.

        Granted, all this stuff about sunspots is pretty speculative, but the last time they disappeared it got cold. Now they are disappearing again.

        Speculation seems the least we can do, and I hope we can do more.
        =================

      • Psst! Kim,

        Perhaps you should explain to Bart, that will global average temperatures and the current conditions at your local airport may be useful, that you don’t live at the airport or a location on the global that just happens to be average.
        You like most human live in the northern hemisphere which has a climate that marches to a different drummer. Which should be of some importance rather than a global average that conveniently smooths climate changes which have major impacts on mankind.

        Then you could have Bart note that Antarctic Ice cores show only a fraction of the climate change that Greenland Ice cores show and if he his more concerned with Antarctic conditions, perhaps he should consider relocating there, where his logic might make sense.

      • Latimer Alder

        @Bart R

        ‘They’re by and large audacious liars, unreliable in almost every detail in their wishful records and manipulative correspondences’

        Saw this just out of the corner of my eye. And somehow the word ‘Climategate’ sprang to mind. But you seem to be writing about monks as well.

        What a coincidence…….

      • Latimer Alder

        @Bart R

        And I wonder how you know that they are audacious liars? Rather than just gullible fools or fantasists? From this distance of time how can you tell.

        In case of any confusion I am referring, of course, to the monks. Not to anybody else like the Climategate Team who might have been referred to earlier. Just in case anybody was unclear. Don’t want anybody leaping to the wrong conclusions……..

      • As a footnote, I should clarify I was not restricting my comments to only Welsh monks.

        I’m not particularly interested in narrow regions when examining global questions.

    • Fred you are the person I would most like to have respond to a couple of graphs. It is generally agreed that significant CO2 caused warming began about 1950. So one would expect that the rate of rise subsequent to that would include not only natural forcing, but anthropological as well. So what explains this.

      http://www.woodfortrees.org/plot/hadcrut3vgl/from:1910/to:1940/trend/plot/hadcrut3vgl/from:1970/to:2000/trend/plot/hadcrut3vgl/from:1910/to:1940/plot/hadcrut3vgl/from:1970/to:2000

      or more simply this

      http://www.woodfortrees.org/plot/hadcrut3vgl/from:1910/to:1940/trend/plot/hadcrut3vgl/from:1970/to:2000/trend

      And when it comes to the pause why not have a little longer view of things.

      http://www.woodfortrees.org/plot/hadcrut3vgl/from:1940/to:1970/plot/hadcrut3vgl/from:1998/to:2011/offset:-0.4

      Now agreed that they have been offset to bring them to the same approximate baseline, but that is not the point. Also I noticed that the same aerosol argument that was used to explain the pause in the middle of the last century is again being proposed to explain this one. The aerosol argument was always double edged for me as it suggested that there were other forcings that could easily override CO2.

      • CMS – why do you start the AGW trend in 1970?

      • CMS- I think part of the evidence lies in the link in my earlier comment to the greenhouse gas forcing for the twentieth century, showing that it was not negligible in the early years. In addition, Figure 2 in Gregory and Forster 2008 depicts some of the forcings for the interval. In essence, the first half of the century was characterized by greenhouse gas forcing plus increasing solar irradiance plus declining volcanic aerosols, while the warming since the late 1970s was characterized mainly by the greenhouse gas forcing with only minor contributions from other sources, including the sun and black carbon (the latter not shown in those links). In other words, the warming factors were probably roughly similar in magnitude but divided up differently. The role of unforced natural variations is not well known for the early years, but their net effect from 1950 to the present can be concluded to be small based on observed increases in ocean heat content that preclude a major exit of heat from the oceans onto the surface and atmosphere.

        Mid-century aerosol “global dimming” and the subsequent partial reduction (“global brightening”) have been well described in the work by Martin Wild and others. Most of the aerosol reductions continued until around 2000 but there has been some evidence for a recent slight increase again (Figure 2 also suggests this).

        I think we know more about climate influences since 1950 than earlier, but the.above factors, plus short term chaotic fluctuations plus fluctuations associated with ENSO can reasonably explain much of what has been observed. There may also be other small influences that are not yet accounted for, but I’m not sure we’re missing anything major.

      • In the Gregory and Forster paper, I intended to refer to Figure 5, not Figure 2.

      • history is not repeating itself.

        No “the pause”
        #Selected data from 1970
        #Selected data up to 2000
        #Least squares trend line; slope = 0.0149702 per year

        plus “the pause:

        #Selected data from 1981.67
        #Least squares trend line; slope = 0.0178242 per year

        plus “the pause”:

        #Selected data from 1991.67
        #Least squares trend line; slope = 0.0217301 per year

        Odd way to stop.

        CO2

      • Fred, I appreciate your response. It is in line with what I would have expected though with the specifics were exactly what I was hoping for. I will have to do some more research apparently. Though I will say that it does seem to make an interesting point. The data show no appreciable difference in the rate of temperature rise between low levels of Anthropogenic CO2 and high levels as per the earlier graphs. ( see above 3 comments) While you have suggested that some studies suggest that there was some earlier CO2 effects they certainly could not compete with the present levels.

        http://www.woodfortrees.org/plot/hadcrut3vgl/from:1940/normalise/plot/esrl-co2/normalise

        Given that similitude of rates of increase, then the question of demonstrating the increased effect of CO2 comes down to theoretical distinctions, such as you have so ably laid out. These distinctions are not readily apparent in the temperature data per se, but rest on theoretical arguments and the peripheral studies which they prompt. This I think is the best argument that the Null Hypothesis must remain with what the data suggests, e.g. no difference, and not with arguments to the contrary. No matter how well founded these arguments are they must stand over and against the easier assumption that the 30 years of heating from 1970 to 2000 is essentially the same as that from 1910 to 1940.
        In addition, as to the present warming hiatus, it is perhaps analogous to the one that started in 1940 following the earlier 30 year warming trend. Thus that we see this same pattern taking shape again after another subsequent 30 years of warming should be suggestive. Again see earlier graph.

      • I learned this critical point, the same slope thrice in the last century and a half, from Phil Jones heself, in response to a question from Roger Harrabin.
        ===================

      • Hi CMS – Readers can visit the links from my set of comments to the temperature trends, the simulation from greenhouse gases alone, and the forcing data from Gregory and Forster 2008 (a small point – I mistakenly suggested their Figure 5 showed aerosol effects after 2000, but those data are from a different source). I interpreted the evidence as above – the warming influences were similar in the first and second halves of the twentieth century, but the apportionment to different factors was different.

        I’d like to add one small point here, most relevant to Isaac Held’s data showing a significant effect expected from ghgs in the first half of the century. It is true that CO2 levels rose to much higher levels later, but it’s important to remember that global temperature is responding to the magnitude of the flux imbalance at the top of the atmosphere (TOA) and not to the level of the forcing agent. When CO2 rises, the imbalance rises, but as the climate responds with a rising temperature, that imbalance is partially restored toward its earlier value, and so the magnitude of the driving force for warming will always be less than the magnitude of the difference in CO2 levels. For this reason, the observed effects are consistent with the change in CO2 over the century.

      • Thrice, Fred, not twice, and going back a century and a half, not a century. Try it again. Try it again. Harder. Harder.
        ================

      • Interesting, too, is that the temp slopes of the three periods after the three rises are similar, too. These argue for the oceanic oscillations being most determinant, and leaves little room for the CO2 effect.

        Where in the World is Wally Warm-it-Up?
        ================

  27. Judith
    Re:

    Here I define “pause” to mean a rate of increase of temperature that is less than 0.17 – 0.2 C/decade.

    Lucia observes UAH: Snaps down in Oct. and plots the UAH temperature together with uncertainty bounds.

    The UAH temperature took a sharp downturn in October– but the trend since January 2001 remains positive (0.064 C/dec):

    This UAH trend since 2001 is only 37% of your 0.17C/decade criteria.
    It appears per your criteria that the UAH global temperature has “paused” for the last 11 years.

    Lucia evaluates GISS since 1980. GISTemp: Up during August! and graphs it.

    The multi-model mean trend since 1980 is outside the ±95% uncertainty intervals computed using “red correction”; thee are illustrated with mustard yellow solid and dashed lines. That means we would deem the multi-model mean inconsistent with this observation if we used red-correction (as is frequently done in climate science.) . . . The multi-model mean trend or 0.207 C/decade is just on the edge of the upper +95% confidence interval which is also at 0.207 C/dec.

    Lucia also posted at the Blackboard: Comparing Land Temperature Reconstructions – Revisited!

    • William Briggs explores what temperature changes are “significant” in BEST’s Worst Work; What Is Significant?

      To achieve statistical “significance” requires three things: a start date from which the analysis begins, an end date on which the analysis ends, and a fixed probability model. All three are arbitrary, at least partially ad hoc, and changing any of them will give different results. . . . Which to choose? And which model? What physical justification do you offer for these three choices?

      Since BEST vs GISS vary as much as 2 degrees between 1990 and 2010, Briggs asks:

      Is it any wonder, then, that some of us are concerned when we hear predictions that, say, fifty years hence the GAT will be 0.5 degrees higher than some arbitrary number, when we cannot even say within that accuracy what the average temperature of Los Angeles was last year?

      Judith gave the start and end dates -”this last decade” and a model:
      (~ linear?) increase of 0.17 – 0.2 deg C/decade.
      What difference does this make? The IPCC assumes most of the change is due to anthropogenic warming vs many skeptics attribute it to natural causes. e.g.,

      James Padgett provides a visual descriptive explanation of surface temperatures primarily tied to Solar variations and the Pacific Decadal Oscillation, plus Atlantic multidecadal oscillations. This presents a popular version of the null hypothesis for naturally driven climate change:
      Why is 20 years statistically significant when 10 years is not?
      1945-1976: PDO into cool phase – corresponding 30 years of colder surface station records.
      1977-1998: PDO into warm phase AND Atlantic goes into warm phase towards the end- 20 more years of warming.
      1999-present:

      After the super El Nino of 1998 temperatures have largely flat-lined and perhaps even dropped slightly. Both the Atlantic and Pacific are in their warm phases and the sun remains at the “high” levels following the recovery from the Little Ice Age, but the Pacific seems to be wobbling cooler and cooler as it shifts back into its cool phase.
      True we are the “warmest decade on record,” but we are also the only decade on record with both oceans in their warm phases in a time of relatively high solar activity.

      For detailed evidence with graphs see Relationship of Multidecadal Global Temperatures to Multidecadal Ocean Oscillations Ch. 3 in Evidence-Based Climate Science, Data opposing CO2 emissions as the primary source of global warming, By Don Easterbrook , 2011

      So, is there a “Pause”? Apparently.
      Why?
      Ah now comes the rub.
      Can we tell from one decade of evidence?
      Santer et al. now appeal to natural variations to explain changes, concluding that we need 17 years to detect major anthropogenic driving.

      So this raises the questions:
      How well do we need need to know natural variations compared to the anthropogenic causes?
      For that, we need to know BOTH what is causing the natural variations AND what is causing the anthropogenic changes –
      AND we need to know them sufficiently well to distinguish between them with some confidence. To date, it appears we do not know any of these.
      We know not whether we are in for another 20 years of cooling or warming. Both models have been proposed.
      Until we can sufficiently quantify changes and compare models, CAGW is “Not Proven”.

    • Do any models show a “Pause”?
      If not, why not?

      In An Initial Look At The Hindcasts Of The NCAR CCSM4 Coupled Climate Model Bob Tisdale explores hindcasts vs observations:

      When a climate change layman (one who makes the effort to look) discovers that the NCAR model CCSM4 hindcasts a global temperature anomaly curve that warms 50% faster than the observed rise from 1900 to 2005 (as shown in Animation 2), they question the model’s ability to project future global temperatures.. . .And when the models don’t resemble the global temperature observations, inasmuch as the models do not have the multidecadal variations of the instrument temperature record, the layman becomes wary.

      Tisdale quotes Trenberth:

      “None of the models used by IPCC are initialized to the observed state and none of the climate states in the models correspond even remotely to the current observed climate. In particular, the state of the oceans, sea ice, and soil moisture has no relationship to the observed state at any recent time in any of the IPCC models. There is neither an El Niño sequence nor any Pacific Decadal Oscillation that replicates the recent past; . . . I postulate that regional climate change is impossible to deal with properly unless the models are initialized.”

      However, if the models of Don Easterbrook etc. show global temperature varying with the Pacific Decadal Oscillation (PDO) (not just regional temperature), then the models themselves are missing major physics and the drivers of both PDO and temperature changes.

      We await models that do include and can predict the earth’s climate state – if that is even possible in light of the chaos of weather and the little known variations in the sun.

    • Xu & Powell (2011) show major uncertainties, expecially in the reanalysis “data”.

      In general, greater consistency is needed between the various
      data sets before a climate trend can be established in any region that would provide the reliability expected of a trusted authoritative source.

      Uncertainty of the stratospheric/tropospheric temperature trends in 1979–2008: multiple satellite MSU, radiosonde, and reanalysis datasets J. Xu and A. M. Powell Jr. Atmos. Chem. Phys., 11, 10727–10732, 2011

  28. Sums it all up really

    Going Down the Up Escalator

    http://www.skepticalscience.com/going-down-the-up-escalator-part-1.html

    plus 1998 + 17 = 2015

  29. Dr Curry quotes Santer as saying temperature records of at least 17 years in length are required for identifying human effects on global temperature. She then immediately goes on to say, “in this context starting the analysis in 1998 is not unreasonable”.
    By “in this context” I can only presume she means the context of her own enquiries, not Santer’s – since 1998 is less than 17 years ago.
    It follows that “this context”, the context of Dr Curry’s enquiry here, is *not* human effects on global temperature.

    That’s how I read it anyway. Anybody know what she is trying to discover?

  30. Despite Al Gore, commercial interests appear to be judging that political support for catastrophic anthropogenic global warming has waned. The current temperature trends would appear to support that decision. See:

    CEO: “The market for carbon capture and storage is dead”

    The market for the company’s technology for capturing and storing CO2 is “dead”, according to chairman Øyvind Eriksen. He confirmed that the closure of Aker Clean Carbon is one of the options. . . .Today, the assumption of support from the government and the consensus among energy companies no longer exist.

    Death of a carbon salesman: Chicago Climate Exchange

    IntercontinentalExchange Inc. told traders Friday that it would shut down its U.S. emissions derivatives platform, a year after acquiring its parent only to suffer sparse trading as the prospects of a federal carbon-reduction plan remain dim.

    The EU market is also in the doldrums.
    More downside risk seen for hard-hit EU carbon market

    Prices of European Union carbon permits have shed a third of their value since the start of the year and could fall further as the euro zone crisis, a glut of carbon permits and an aviation spat depress market sentiment, analysts said on Friday. . . .”There is no debate that the ETS will end up massively oversupplied in the Phase II (2008-2012 trading period) and beyond,” said Kris Voorspools, a director at 70Watt Consulting. “Carbon may well stay in the sub-10 (euros) range for a long time.”

    • This bubble was pervasive, and since energy use precedes even housing the repercussions will be even worse than the contortions produced by the housing financial bubble.

      You ain’t seen nuthin’ yet.
      ==============

  31. “In today’s news, the year 2010 has seen a 6% increase in CO2 from 2009. Given that the trace gas radiative transfer model describes photons moving at near the speed of light, shouldn’t we have seen a 6% increase in global temperatures? if not, why not?”

    It’s the increase in atmospheric CO2 that allegedly causes global warming, not anthropogenic emissions. There’s no direct mechanism for emissions to be causing warming, except indirectly by adding to atmospheric CO2.

    Human emissions and atmospheric concentration of CO2 are not necessarily related.

  32. Has the rate of warming continued unabated, or has there been a pause in the warming?

    Seeing is believing!

    http://bit.ly/s4cUK3

    The facts are there has been a pause, and IPCC’s projection of 0.2 deg C per decade has not happened.

    • Excellent graphic.

      i find the least amount of smoothing is a good thing.. it keeps perspective of what is really occurring…

    • That graph is a little too busy, but it looks like global warming was predicted and global warming occurred. It looks like continued global warming is predicted, which seems reasonable given predicted population increases and rising per capita use of fossil fuels.

  33. September 2011: 389.00 ppm
    September 2010: 386.80 ppm

    difference is 2.2 PPM….
    0.0056555
    far cry from 6%

    • 6% increase in human CO2 emissions, not atmospheric concentration. The two are not necessarily related.

    • Your numbers are the monthly average measured at Mauna Loa. Today’s DOE report is for CO2 emissions from fossil fuel and cement manufacturing, which increased 6%. Emissions from these sources are equal to about 1% of total atmospheric CO2, annually, so the ~0.5% annual increase in CO2 has other contributions as well: CO2 emissions not accounted for above, climate feedback, deforestation, etc.

      • simply amazing isn’t it… a 6% “perceived” out put increase does nothing to change the global rate of increase. yet man is causing all warming…

        Statistical analysis is not their friend..

  34. “IMO, the significance of the BEST data in terms of the temperature record of the past 50 years or so is that it puts to rest the concern that Phil Jones and Jim Hansen have “cooked” the land surface temperature data.”

    Amen, Dr. Curry !

    Those who alleged Jones and Hansen “cooked” that data should do the right thing and apologize to these scientist

    • Apologize? No way, in fact a good tar ‘n’ feathering accompanied by a healthy dose of rotting vegetables in the main public square of every major city in the world is too good for these shonks, especially the latter masterchef.

    • “it puts to rest the concern that Phil Jones and Jim Hansen have “cooked” the land surface temperature data”

      No, it doesn’t.

      Andrew

      • Only their hairdressers know for sure, and there was a toxic spill in the beauty salon a couple of years ago. Mitigation of the hazard proceeds apace, but all the workers are getting sicker and sicker.
        =================

      • The need to defend these two individuals is obviously motivated by something other than science. If the science itself was the most important thing, bad apples would be tossed out, in favor of keeping the process clean. When tribalism dominates, the bad apples get to stay and the data gets disappeared.

        Andrew

    • Ha ha ha ha

  35. You choose 1998 as a starting date for testing whether or not the temperature data from that date forward shows any significant trend *after* looking at the data and perceiving a pause at that point. You choose a completely different date for a different data set. This is post hoc analysis, which means that most of the statistical tests used to measure trends and whatnot are invalid. Because you are fitting to look for a trend *after* selecting the data that looks flat, the real 95% confidence interval of the trend in temperature (or ocean heat content) over any of these intervals is much larger than what you are presumably calculating.

    I can generate completely random data without any trend with noise mimicking that in annual temperature data and quickly find a 13-year span somewhere in the mix that would appear to have a trend that’s positive within a 95% confidence interval (with an equal probability of seeing a “significant” decline). The monthly attempts to look back at every possible time span in every observational record and identify some “significant” decline aren’t science; they’re numerology.

    “Lack of statistical signficance does not negate the existence of a pause as defined here” — Who is claiming that there’s definitive evidence that global warming has not paused? You claimed that it has paused, and your definition of pause now appears to be, “Anything that looks to anyone like a pause in one moving average or another over any time period, but is not a pause according to any statistical test.” I agree that global warming has undoubtedly paused by that definition.

    • Zach, from the beginning she said there was no evidence it had not paused.

      So you also disagree with the greenwire article scientists who refer to the pause?

      • She said that there was a lag/slowdown in addition to saying that there wasn’t enough evidence to say that it hadn’t paused. She’s defending the latter point (that we don’t know if it paused or not with any certainty) rather than her statements that are actually controversial. The only definition of “pause” that’s satisfied in the data is the one I give – Curry looks at it and thinks she sees a pause; well, fair enough. She’s also laughably redefining paused to mean slowed down for some reason.

        And yes, I disagree with any scientist who looks at the data sets that Curry posts here and says that they’re any different than what could be reasonably expected from a noisy, warming data set (and, for that matter, any scientist who looks at similar data and says the opposite).

  36. Norm Kalmanovitch

    The albedo is assumed to be 30% of the estimated 342watts/m^2 of solar flux averaged over tyhe Earth surface which is 102.6watts/m^2.
    What if reduced cloud cover changed this to 29% and the albedo was reduced to 99.18watts/m^2 or increased to 31% resulting in an albedo of 106.02watts/m^2?
    Supposedly a doubling of CO2 is supposed to produce 3.71watts/m^2 (5.35ln(2)= 3.71) and changing the albedo from 30% to 29% increases the incoming solar radiatyion by 3.42watts/m^2 so this could be and is most likely the cause of observed warming.
    Project Earthshine shows the albedo decreasing to 1998 and then increasing since perfectly matching the end of global warming in 1998 and the start of cooling after 1998.
    If you do a web search on “It’s the sun stupid” you will find articles like this:

    http://fullcomment.nationalpost.com/2010/05/21/its-the-sun-stupid/

    Which is about as good a commentary as one can get for the idiotic rhetoric about CO2 emissions from fossil fuels causing catastophic global warming as the Earth continues to cool!

    • After that headline, “It’s the sun stupid,” we find the following statement in the last paragraph of the article:

      “There is as yet no answer to how the Sun affects Earth’s climate.”

      That’s pretty funny.

      • Norm Kalmanovitch

        seeking this answer is what used to be called “science”; trying to explain why the prediction of continued accelerating global warming from the 52% increase in CO2 emissions from fossil fuels since Hansen predicted this in 1988 has failed to materialize and trying to explain why the Earth has experienced no global warming for over a decade in spite of the 26% increase in CO2 emissions from fossil fuels is what is funny

  37. In the context of all these questions, and to take a longer-term perspective, one really should ask what forcings drove short, medium, and long-term climate changes on the planet prior to the advent of a species that could potentially alter the climate? To begin to answer these questions we really need a close look at the paleoclimate data. What do we find? Milankovitch cycles, solar output variations, volcanoes (aerosols), and carbon dioxide levels are the drivers of climate. Ocean cycles are not included here because they are a response to a forcing, and not a forcing themselves. Often times these forcings are working in the same direction, and of course sometimes they work in opposition. So, getting back to the issue of the plateau in temperatures seen in the past ten years or so, if we take the forcings mentioned above and add them all together, can we make a scientifically justified case for this plateau? The answer is yes. We know aerosols have been measured as increasing (both from volcanoes and anthropogenic) and solar output has been the lowest in a century. These two forcings to the cool side have dampened out any forcings to the positive that may have come from CO2. Once the sun breaks out of it funk, even if it’s 20 years from now, we would certainly expect temperatures to begin to hit consistent highs once more– though I would expect to see them long before that.

    • ” Ocean cycles are not included here because they are a response to a forcing, and not a forcing themselves”
      Seems a pretty reasonable statement but hasn’t Kevin T already established that Ocean physics is not always so straightforward and may not always follow land physics
      I refer you to the seeming teleportation of heat energy from Oceanic surfaces to abyssal pipelines that explains the modelled budgetary deficit at the cost of a physical mechanism that explains the lack of observed intermediate traffic!

  38. Has the climate recently shifted?
    Kyle L Swanson

    If as suggested here, a dynamically driven climate shift has occurred, the duration of similar shifts during the 20th century suggests the new global mean temperature trend may persist for several decades. Of course, it is purely speculative to presume that the global mean temperature will remain near current levels for such an extended period time. Moreover, we caution that the shifts described here are presumably superimposed upon a long term warming trend due to anthropogenic forcing. However, the nature of these past shifts in climate state suggests the possibility of near constant temperature lasting a decade or more into the future must at least be entertained. The apparent lack of a proximate cause behind the halt in warming post 2001/02 challenges our understanding of the climate system, specifically the physical reasoning and causal links between longer time-scale modes of internal climate variability and the impact of such modes upon global temperature. Fortunately, climate science is rapidly developing the tools to meet this challenge, as in the near future it will be possible to attribute cause and effect in decadal-scale climate variability within the context of a seamless climate forecast system [Palmer et al. 2008]. Doing so is vital, as the future evolution of the global mean temperature 183
    may hold surprises on both the warm and cold ends of the spectrum due entirely to internal variability that lie well outside the envelope of a steadily increasing global mean temperature.

    Here are my climate shifts=>[1880s,1910s,1940s,1970s,2000s]

    http://bit.ly/uXy8jw

    • Swanson: Moreover, we caution that the shifts described here are presumably superimposed on a long term warming trend due to anthropogenic forcing.

      Such presumption, from such ignorance.
      ==============

  39. Per Swanson, pick any trend not using 1998 through 2008 (the shift). In his example he started in 1979.

    BEST is going to put GisTemp or NOAA on top, and the shift will take it in shorts.

  40. Judith

    As a layman I really cannot understand the scientific relevance of global mean temperature. No-one experiences global mean temperature. In fact most of us survive fairly major swings in temperature from day to night and season to season. What is it supposed to tell us? Is it a proxy for heat energy in the earth system? If so how good is it? As far as I am aware temperature cannot be averaged? And the various data sets show a mean (T.min + T.max/2), not an average? which seems to me to be completely meaningless. Is it not the case that substantially more energy is required to raise the temperature in the tropics than at the poles? And yet is it not true that all mean temperatures are treated as having the same value? If the anomaly decreases by 0.5c in the tropics and increases by the same amount at the poles is it right that the data sets would show no change in ‘global warming’? How representative are the measuring sites? And who got to decide what the optimal global mean temperature (which as I say appears to have no meaning) should be? I appreciate that I may be well off track here but I really would like to know just how scientific this whole global mean temperature caper is. Thanks in advance

    Gary

    • Gary

      It is the temperature equivalent of the average heat emitted by the globe to outer space that the global mean temperature refers. There is a relationship called Stefan–Boltzmann law that directly relates the heat emitted by a body to its average temperature.

      It is amazing how indeed a stable property of the globe is its mean temperature:

      http://bit.ly/v6RXQV

  41. Here I define “pause” to mean a rate of increase of temperature that is less than 0.17 – 0.2 C/decade. Why 0.17 -0.2 C/decade as a threshold?

    I’m going to quibble a bit until the Breakpoint below, as I’m irked by our kind host’s usage.

    Isn’t it a bit premature to make 0.2C/decade the null hypothesis on which to claim a pause, as it’s a rate that has never actually been observed on any statistically significant span of time?

    Wouldn’t that rate need to have happened first, before it could pause?

    Also, HadCRUT doesn’t really provide much confidence on the post-1998 timeframe. Certainly not enough — however global it may be — to base claims of discriminating between 0.17C and whatever the claimed rate on the utterly invalid sub-decadal trendlines.

    Also, why 0.17C, and not 0.163C, if you’re using the imprecise HadCRU?

    This strawman rate of warming that never was that’s magically paused seems contrived simply to allow people to throw around the pause word, when what is meant about the warming appears to be “failed to accelerate as much as predicted as soon as predicted” unless one means “accelerated warming” whenever one says “warming.”

    If Drs. Curry and Muller always mean “accelerated warming” in their expert opinions when they say “warming”, and use “pause” to refer to the acceleration only, then we’re in much deeper trouble than we thought.

    Conventional statistical and graphical analysis, on the other hand asks how consistent is the range of observed temperatures on the subject period with the expected range given the past trend, not the expected range given what someone from the IPCC said, especially noting that people from the IPCC are given to making predictions not based on anything in the IPCC’s science.

    WFT is a fair tool, but has its limitations.

    http://www.woodfortrees.org/plot/best/mean:13/mean:11/from:1976.5/plot/best/from:1976.5/trend/plot/best-lower/from:1976.5/trend/plot/best-upper/from:1976.5/trend/plot/best/from:1998/trend/plot/best-upper/from:1998/trend/plot/hadsst2gl/from:1976.5/trend/plot/best-lower/from:1998/trend/plot/hadsst2gl/mean:13/mean:11/from:1976.5

    Not what I’d normally do to demonstrate that the post-1998 period is extremely consistent with the pre-1998 trendline, but it does the job.

    There is zero basis for claiming a pause within the evidence.

    Sophistry that manufactures a pause of something that hadn’t actually started in the first place.. not what I’d have hoped from the BEST Team.

    Breakpoint.

    Even after 2.0C/century happens for a couple of decades in a row (which looks likely within the next sixty years barring aerosol emission increasing much faster than projections indicate), I’d still expect actual pauses to happen quite often. Perhaps one third to one half the time, if the present trend continues, on spans as long as almost thirty years in the most extreme case, there’ll be ‘pause’.

    How meaningful is ‘pause’ meant to be?

    Is it meant to signal a middle ground between pure GHG AGW and Natural Variability?

    Is it intended to agree with both camps in a way that makes neither happy?

    It can’t be intended as a precise description of actual observations, as.. it’s just not technically what ‘pause’ means.

    Perhaps ‘fishtailing’ is a better term than ‘pausing’. It’s a commonplace behavior in chaotic systems as the phase changes from one periodicity to another. Maybe that’s what’s happening.

    • Cling bitterly to your aerosols, but albedo is pointing at you.
      ===============

    • Bart, just a heads-up that I’ve been convinced that my taking half the uncertainty value to generate best-upper and best-lower was not correct, and the values should be +/- the full amount. I’ve changed this today, with the result that your confidence trends are further apart than before.

      Also, I’m not at all sure that the trend of the confidence has much to do with the confidence in the trend… Now if only I could work out a simple way to generate trend-upper and trend-lower as well, a lot of arguments might be solved :-)

      • Paul Clark

        I appreciate the head’s up, and I agree with your conclusion. (I’d wondered why I was seeing such narrow bands, and now you’ve removed one of the big concerns I had about wft, so thanks for that.)

        Trends of confidence themselves have an interesting relationship to confidence of trends. I believe others have discussed the ‘fat tail’ product of that relationship, if that’s what you mean.

        While you’re tweaking the increasingly wonderful wft toolset, if you could find a way to show parts of trend lines (they vanish if you put the “/from” and “/to” after “/trend”), it’d make demonstrating some arguments plainer.. and what’s with derivatives and normalization? They seem.. underdeveloped.

        Please continue the excellence.

      • Indeed and seconded.

        Not said enough, and your work is misused by almost all of us, but you are the most universally appreciated guy in the climate world. All positive.

        Thanks from an occasional misuser…

  42. So, I could listen to the armies of scientists and statisticians arguing about pauses and plateaus and significance and periods.

    Or I could look at the graphs.

    Hmmmm. But which to trust, which to trust? My eyes, or the scientists and statisticians?

  43. Judith: Your definition of a pause is somewhat incomplete: a trend of 0.17-0.2 C/decade isn’t useful until you include unforced variation to your model. Pick the observed unforced variation during one of these earlier periods. Now ask if your model (without a pause) is consistent with the observed data?

  44. Future is ‘cool’
    In the graph below, the blue line is derived directly from the CETemperatures. Similar oscillations are to be found in other natural events. Its direct extrapolation (inset) shows further cooling.

    http://www.vukcevic.talktalk.net/CET-NV.htm

    Modern Warm Period – MWP2 is over !

  45. I think you are overstating the consensus of a pause in global warming, plateauing of temperatures, etc. Tamino basically kicked me off his blog for claiming this. The argument is that since temperatures have not returned to the long term average, any slowdown is non existent as the trend is still positive, and in fact the trend has not changed much.
    So 1998 to 2010 may be the same temperatures, but 2009 is warmer than 1997, 2008 is warmer than 1996, etc. so the long term average is still growing.

    • Joachim Seifert

      To MikeN:
      Please look at HadCRUT3 global temps and you will see the beginning of the TEMP-PLATEAU, since the tipping point in 2000….. which will continue for the decades to 2045 and then comes the onset of a downswing thererafter……
      Reference: see my reply to Judith, just a short while ago…..

  46. There is a neat graph on this link which makes the point better than any number of words.

    http://www.skepticalscience.com/going-down-the-up-escalator-part-1.html

    • This skeptical science web site must be given the best prize for obfusication.

      Skeptics don’t deny the warming from 1970 to 2000.

      What we claim is a shift has occurred in the 2000s to slight cooling=>http://bit.ly/uXy8jw

      • sorry

        [The] skeptical science web site must be given the best prize for obfusication.

      • Joachim Seifert

        The longterm warming finished at its tipping point in the year 2000,
        tipping into a flat temp-PLATEAU, which will continue for 3 more decades… Reference on Amazon.de: ISBN 978-3-86805-604-4, all transparently for everyone to calculate….. (Amazon.de, not com because pocket book…)
        The warmists do not recognize this tipping point by insisting on the old warming trend of before 2000 and putting it onto the future…..
        which will get them more and more into explanation squeeze (see latest on Trenbert: – Hiding of temp somewhere in the ocean, Hansen -temp/heat Hiding in the pipeline – in both cases: “HIDING”! , because
        temps will not rise globally any more….we reached the top of the flagpool already….. The Hiding argument will get shallower from year to year, as the flat Plateau will 100% continue…..

      • “The longterm warming finished at its tipping point in the year 2000″

        Really?

        http://www.woodfortrees.org/plot/uah/plot/uah/from:2000/trend/plot/uah/to:2000/trend

      • I am merely presenting the record you should be using.

        skeptics on various blogs have been claiming the satellite records are superior to the surface records PLUS HadCRUT is maintained by Phil Jones, the man none of you trust.

        So *why* are you all citing HadCRUT to back up your “end of warming” claims? The two-faced nature of your approach is as brazen as it is reprehensible.

      • lolwol,

        I’ve always stuck with HadCrut, since it’s the one IPCC seems to rely on most.

        Is the IPCC wrong?

        Are you ready to embrace the UAH data set?

      • Joachim Seifert

        John, please go into Woodfortrees again and take a decade 2001-2011 and try to get El nino 2010 a little compensated ( reduced) and La Nina 1999-2000) compensated (increased),. These Ocean currents delay and “mask” and have to becompensated one with the other. Then you will see the horizontal trend-line after 2000/2001 until now. also compensate the 2010 El Nino peak with the (this winer 2011/2012 winter La Nina cold). And the tipping poit calculation you will fing transparently presented for everyone in the German amazon.de ISBN 978-3-86805-604-4, I am slow to translate the booklet, sorry, folks……

      • Girma

        “Skeptics don’t deny the warming from 1970 to 2000.”

        Name any year from 1970 to 2000, and I will find a published or internet quote denying global warming made in that year.

        Skeptics of some sort have recycled the very same argument over and over, during times we now know to a certainty were warming globally.

        Just as you are again reverting to your repeatedly refuted attempt to manufacture a sine curve by manipulating the curves so artificially as to lead to no other conclusion than academically fraudulent intent.

        Give it up, Girma. You’re done.

      • Joachim Seifert

        Skeptics deny warming from 2001 to 2011 (also compensating El Nino 2010 with la Nina cold winter 2011/12…..) because 2000/01 was the tipping point and we are on a peak temp. Plateau from which it can go only downward later on….. This way the IPCC fulfills the warming goal of +2 C, because we will stay substantially below this projected level……
        JS

      • Joachim Seifert

        Did you even read the first line?

        Every year since 1970 has been claimed as a tipping point by someone, often on better reasoning than yet another ENSO, regardless of what the IPCC has said or done.

        Here you go, http://www.sciencedaily.com/releases/2001/06/010615071248.htm is just one published (and refuted) claim of the end of global warming made in 2001 covering a prediction of CO2 levels. CO2 hasn’t paused, as the author implied it would by now.

        And for the world class wrong about AGW citation for 2001, “We got an energy crisis in America that we have to deal with in a common sense way.” GW Bush, March 2001, on Kyoto. Mr. common sense himself. Why, when I think of common sense, the face that pops up in front of my eyes is GW Bush.

    • SkepticalScience? Please…

      • Dikran Marsupial

        Refuting the argument is normally a more convincing argument than an ad-hominem. Just questioning the source of an argument is merely a tacit admission that you have no counter to the argument it provides.

      • A word to the wise, DM; SkepSci has an agenda to advocate, and that impulse has so tormented their arguments as to make one scream.

        How about you make their argument, if you can adequately express it?
        ==================

      • Dikran Marsupial

        Kim, all you have done is provide a tacit admission that not only do you not have an answer to the argument (as indicated by the ad-hominem), you can’t even make the effort to find out what the argument actually is. The blogsphere is full of trolls, and your comments today show pretty clearly that you are not actually interested in the answers to your questions, so I won’t waste my time answering any more of them.

      • So you can’t adequately express their argument? Bummer.
        =============

      • Son, the questions I have don’t have answers yet, so don’t waste your time blowing smoke. Nonetheless, I am interested in the answers, else why would I waste my time asking them?

        What’s the meaning of this pause, and is the sun involved? A question more worth your time exploring than trying to answer from your ignorance.
        ================

      • Do you say that to your side when they attack WUWT?

      • Dikran Marsupial

        Does that change the fact that an attack on the source of an argument is no substitute for an refutation of the content of the argument? No. The climate debate is full of ad-hominems and insults and implications of dishonesty etc. It would be far better all round if we ALL concentrated on understanding the science and gave the rhetoric a break for a while.

      • I’m all in favour of that. When your side dishes out the attacks I feel quite justified in sending the attacks back. Best to site the original source, not the messenger then.

  47. Joachim Seifert

    Dear Judith, you say:
    …….” Statistical analyses of various data sets over various periods aren’t all that interesting in the absence of an hypothesis that is related to a physical mechanism. I hope that this post stimulates more meaningful analyses of the recent data record……….”

    …….Answer: This is the crux of the matter….! Guesswork and assumptions derived from statistics are waste of time….. we need a “hypothesis of a workable physical mechanism”, which is able to explain
    1.) Observed Warming to the year 2000 (as tipping point) +
    2.) Followed by a temp.PLATEAU ever since 2000, which makes evident
    that NO MORE future temp-increases (11 years equalized, El Ninos will
    still happen) will occur. I.e. to say, in other words: Null hypothesis is
    proven, the globing warming issue is settled: “The end of global
    warming” (Book title) has been reached…..

    No problem at all, the answer is given in reference:
    Book ISBN 978-3-86805-604-4 ……. The reference,
    until today, not proven wrong or even pointed out as possible wrong….
    due to the fact, that only hard data without use of “uncertainty”- inflicted models are used.
    If you like to give me a post, I would be happy to explain the approach to the interested community…..this is an solicitation….
    JS

  48. I find the insistence of those most strident in their claim that the undeniable trend of warming in the late 20th century continued if not accelerated in the noughties, to be delusional, if not in denial.

    Here, starting in 1991, is a 10 year forward moving trend of trends using GISS data, I hope that even the most ardent warming advocate will open the other eye.

  49. To me, this thread and the previous one on the null hypothesis go together. The fact that serious scientists are discussing this at all shows that Kevin Trenberth has won in his desire to have the null hypothesis reversed. When I was taught physics, the idea was that one proposed a hypothesis, and then went out and found the observed, preferably experimental, data to prove the hypotheis was correct. Until this data was available, the idea remained just that; a hypothesis.

    What the proponents of CAGW have done is to use a series of non-validated models, and other dubious techniques, such as no-feedback climate sensitivity, to claim thjat they have proved that CAGW is correct. Now it is up to us skeptics to use the observed data to prove that CAGW is wrong. This is the wrong way round. It ought to be up the proponents of CAGW to find the observed data to prove that they are correct.

    But in the inverted world of science in the CAGW era, the onus is on the skeptics to produce the observed data to prove that CAGW is wrong. Luckily, as Girma so rightly points out, the observed data is doing just that. The observed data proves that CAGW is wrong, and as we get more and more data, this is becoinmg ever more clear. There is no CO2 signal in the observed temperature/time data.

    • Joachim Seifert

      Jim each word of you is mine……

    • Michael Larkin

      Is this strictly speaking correct? Isn’t the philosophical principle that one posits something is so, makes a prediction of what will happen if it is so, and rejects it if that doesn’t happen? Whereas if it does happen, that is evidence supporting the hypothesis, but not unchallengeable truth?

      I certainly agree that the climate science establishment has tended to assume something is so and gone looking for confirmatory evidence, and suspect that there are now faint glimmers of it reverting to the more traditional approach.

      As I see it, the prediction is, that if anthropogenic CO2 is a significant driver of global warming in recent times, and has continued to increase, then temperatures should have continued to increase in the last decade or so. I feel sure that if it had, it would be being claimed as supporting evidence (though shouldn’t be claimed as unchallengeable proof).

      Like it or lump it, there is increasing acknowledgement that over this period, temperatures have not risen as much as would have been expected were the hypothesis unqualifiedly so. The question is, what does one do about that? I think it has for the first time put a dent in the confidence and bluster of the establishment. Some are putting forward the hypothesis that confounding factors such as aerosols are masking the anthropogenic effect, but a few are beginning to wonder, along with the sceptics, whether the initial hypothesis might be wrong.

      My question would be whether the “confounding factors” are a real possibility, or whether they have a role akin to that of epicycles in Ptolemaic astronomy, i.e. function to keep alive a hypothesis that has become a dogma. I don’t know myself, but based on ordinary observation, have suspicions that the latter is the case. For the first time, I think that at least some in the establishment are beginning to feel what it is like to experience scepticism. Whether or not the anthropogenic CO2 hypothesis is correct, and if so in what degree, that is an outcome devoutly to be wished.

  50. Why are land surface temperatures running much hotter than atmospheric or oceanic temperatures? That is what all the datasets are telling us.

    We are told it can’t be UHI, or land change useage, etc. So what is it?

    PS You can’t blame AGW, because the atmosphere should be running much hotter than the land or the oceans.

    If you can explain this then you may understand why the planet has stopped warming over the past 13 years.

    • Joachim Seifert

      To Mac:
      All these aspects are shown in ISBN 978-3-86805-604-4 on Amazon.DE, not on .com (because Pocket book): There is still a slight net irradiation gain, due to Earth’s orbit libration (see libration – Wikipedia), which
      heats the land further, but due to increased ice melting from higher
      radiation gain, the oceans (Antarktis in particular) cool into more La Nina conditions…….

  51. Judith,

    The question that should be asked is, what physical changes has the planet and sun gone under in the last 50 years?
    Temperature readings do not look at any changes just if their is a change in statistical data.

    • Joachim Seifert

      This is exactly the point: The Earth’s orbit is not an airplane’s path, but it does pendulum swings along its progressive track, which have not been taken into account by the IPCC (they only did changes in eccentricity of the orbit and remained silent about the pendulum swings). You can convince yourselve with wikipedia : the motion is called “Libration” (an animated picture for the Moon, the Earth does the same…)
      ….therefore: The Libration RF (Libration forcing) was kept under the table
      and this missing power is the explanation everything, including the
      resulting temp-plateau since 2000, which will continue for 4 more decades, until temperatures will start to significantly receed….
      JS

      • Michael Larkin

        Thank you Joachim. I’ve been trying in vain to have the least understanding of what Joe has been saying so often and so long. If (and it’s a big if) it has anything to do with what you have said so clearly, then maybe he has a point.

      • Joachim Seifert

        This is why IPCC forecasts are wrong: They do not take changes in the Earth’s orbit into account (only “eccentricity”( not the pendulum swing movements (see Wilipedia: Libration) The Libration forcing increased temps to their 2000 level and from this tipping point on, temps will stay flat for 3 more decades, which can easily and transparently for everyone interested be calculated…..
        JS

      • If (and it’s a big if) it has anything to do with what you have said so clearly, then maybe he has a point.

        That’s the spirit, they are your guys, so feel free to take ownership.

      • Poor Web and his ‘Law of the Pack’. Joe is his own person, as are many skeptics. Is that why the true believers have such disdain for skepticism? Is it envy really?
        =============

      • Poor Web and his ‘Law of the Pack’. Joe is his own person, as are many skeptics. Is that why the true believers have such disdain for skepticism? Is it envy really?
        =============

        I recognize projection when I see it. The Cimate Etc comments section metaphorically acts as a giant projection screen.

        “true believers” => projected right back at you
        “own person” => …
        “law of the pack” => …

        and on and on and on

      • Mirrors, mirrors, down the hall,
        Endlessly projecting
        From the Fun House wall.
        ============

      • Is it envy really?
        =============

        Projection again. Poetry is for those that lack the analytical skillset.

  52. Judith,

    We have record shattering precipitation over the majority of the planet and yet that does not matter to climate science. Just temperature data.
    Earliest snows and growing glaciers, yet their is a pause in temperature trends.
    Ice Ages are precipitation based.

  53. Leap second data shows that the spin rate of earth has increased. That says ice volume has increased and ocean level has dropped. The warming has paused and the cooling has begun. Warming will resume after a few hundred years of cooling. As the little ice age followed the medival warming, cooling will follow the modern warm period.

    • Your assumptions are that Earth 2011=Earth 1300, and that all cycles repeat endlessly and predictably. It doesn’t and they don’t.

      • They may not repeat, but they sure rhyme.

      • Michael Larkin

        A beautiful way of putting it! :-)

      • Yes, the stable cycle that has been in place for ten thousand years will continue for thousands of years to come. A trace of CO2 will not change that. The stability in a narrow range that has occurred in this warm period has not been matched in the ice core history. Before the most recent major warming out of the last major ice age, the range of warming and cooling was much more severe.

      • Even a sensitivity of 1C warming per doubling of CO2 would completely destroy the “stable cycle”. 1C warming is more warming than has happened over the 20th century.

        And of course if either sensitivity is higher than that, or we more than double CO2, both of which are more likely than not, then the warming is going to be even greater than 1C.

      • any warming melts more arctic sea ice and then it snows more and cools us. there is powerful negative feedback to temperature through ice albedo from snow. when it is warm it snows more. it does not matter if CO2 or anything else causes the warming, the snow cools us. Earth is now warm and Arctic Sea Ice Extent is low and the snows have started.

      • History is the best prediction for the future.
        When the history is stable, the future will be stable.
        When the models are unstable, they are wrong.

  54. “IMO, the significance of the BEST data in terms of the temperature record of the past 50 years or so is that it puts to rest the concern that Phil Jones and Jim Hansen have “cooked” the land surface temperature data. This has not been a serious concern among the people paying close attention to this issue and who actually read the journal publications and look at the actual data; but it is a concern in certain circles, and in the U.S. this concern has been raised by at least one Republican presidential candidate. The relatively small discrepancies between the BEST and the GISS and CRU data sets are of some interest; the apparent discrepancy with GISS has been resolved. Note: the CRU data set shows less warming than BEST over the past 15 years.”

    So you accept the BEST data and accept the BEST code as representing state of the art knowledge of humanity?

  55. Nebuchadnezzar

    For what it’s worth…

    Judith shows the evidence for the pause in warming, but not the evidence against. In certain circles that could get you accused of cherry picking, but I think in this case the evidence is showing something slightly more nuanced than “global warming has stopped/no it hasn’t”.

    First HadCRUT3 has a poor coverage in the Arctic. The trend is higher in NCDC which has improved coverage of Canada and Northern Russia which have been quite warm these past few years. It’s higher still in GISS, which interpolates those high temperatures over the Arctic ocean. If you compare HadCRUT, NCDC and GISS over the region where they all estimate temperatures (roughly 60S to 60N), they come out pretty near the same (there are still differences, but they’re smaller).

    This suggests to me that Arctic warming and how well it is represented plays an important role in observed global temperature trends of the past ten years. HadCRUT3 doesn’t sample the Arctic at all well, so it probably has a cold bias if you consider it as an estimate of global temperature.

    There are very few measurement stations in the Arctic over land and even fewer over the oceans. This suggests that the uncertainties in measurements from these regions are larger than in other regions, and this will be exacerbated by the high variability. Most of the HadCRUT3 uncertainty range arises because of the poor coverage at high latitudes.

    If you take the AR4 models that give the 0.2C/decade warming over the next decade and look only at the Arctic (north of 60 N or so) then the observations have warmed much faster than the mean. No pause there. If you look at everything equatorward of 60S and 60N then the observed temperatures have warmed much more slowly than the mean. Across this range, land temperatures have continued to warm at a fair clip, but SSTs have not warmed as much.

    This suggests a number of questions to me. 1 – did the circulation-driven fall in Arctic sea ice (which AR4 models don’t do a great job of) have anything to do with the recent jump in Arctic temperatures and if so, could we get the ‘right’ global temp trend for the ‘wrong’ reasons. 2 – why have SSTs flatlined more than land temperatures over the tropics and midlatitudes. 3 – why do people suddenly forget that observations aren’t perfect, particularly at short time scales where systematic AND random effects are important, when they discuss this issue.

    I’m not about to suggest any solutions here, but I will note that if we ask “is it warming” then effectively, as Judith points out, we are muddling a prediction together with an observation: are we in the middle of a continued warming? Given that it’s a prediction it then matters a great deal what model (mental, computational, or otherwise) you use to make that prediction. The answer to the question will be model dependent.

    However, what people seem to be doing is using this 10-year (or however long) period to decide between these different mental models. Unfortunately a 10-year period such as we have just seen is consistent (on its own) with all sorts of different hypotheses and futures and mental models, particularly if one factors in the uncertainties in the observing system. A slight slowdown, considered on its own, could be the start of a new ice age, or it could be a ‘speed bump’ on the way to a hot house earth, or anything in between.

    By plotting and replotting global temperatures with various trendlines through them, we won’t learn anything more than we already know (so stop it, it’s boring). Arguing about start and end dates to fit straight lines to data that are manifestly not straight lines is where that leads. The question really is, can we understand every single wiggle in the observations of the climate?

    No one has ever looked at a ten-year period with such intense scrutiny, nor has had the observing systems or tools to do that effectively. Some would argue that we still don’t have the necessary observing system to do it. It’s not surprising that people are scratching their heads. However, scratching is not all that they’re doing. There are many different potential explanations for the hiatus of varying degrees of plausibility: Chinese aerosols, background natural aerosols, mini volcanoes, solar variability, observational biases, heat sequestered into the deeeeep ocean, internal variability, stratospheric water vapour, cosmic rays…

    The climate is a messy system and traditional attribution looking for the reasons for a warming of several tenths of a degree over a century can only reach the conclusion that it is ‘very likely’, what chance, consequently, does anyone have to confidently attribute changes of a hundredth of a degree over a decade?

    Almost zero. But there’s no doubt that by trying to understand we will learn something new about the climate along the way.

  56. Dikran Marsupial

    Prof. Curry writes: “Santer et al., searching for the AGW signal amidst the natural variability noise. Santer et al. argue that “Our results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature.”

    So in this context, starting the analysis in 1998 is not unreasonable.”

    Is it just me or is there a bit of a disconnect there!?

    Also “If one is seeking to identify an anthropogenic signal, one should choose years at each end point that are neutral in terms of ENSO and also the 9.1 year AMO signal discussed by Muller et al. ”

    well that criterion isn’t fullfilled either, as is well known from the many analyses where the effects of ENSO have been subtracted from the time series (after which there is no evidence of any pause in the warming, suggesting that the pause is due to the effects of ENSO).

    Starting the trend in 1998 is utterly unreasonable by both of the criteria listed by Prof. Curry.

    One thing that dissapoints me greatly is that Dr Curry has made strong statements about there having been a slowdown in the warming (or words to that effect), but in this post she does not give unambiguous answers to ANY of the questions, not has she provided an anlysis of the data that would support the statements that she has made.

    In science if you want to make a claim, it is incumbent on you to show that there is solid evidence to back up your claim. In this case, evidence that there has been a statistically significant difference in the rate of warming. However there isn’t one, and not recognising this fact does not encourage me to accept Prof. Curry’s claims.

    • “In science if you want to make a claim, it is incumbent on you to show that there is solid evidence to back up your claim.” Funny you should demand that. The AGW Prophets haven’t even come close to doing what you demand of Judith. Maybe you should take your demand to Trenberth or Mann first. Then get back to us.

      • Mr. Richard Wakefield, I am with you on this point.
        Until the AGW crowd produces the original records to back up all of their data sets, they have nothing. Let them get digging or whatever they need to do, and they need to explain to the world what happened to all of the collected documentation used to support their data. Where is it buried… remember PJ even said: ‘…whatever we may or may not have done’… just what did they do? That is the Big question at this stage. Why would anyone destroy the originals unless they would not agree, with what is being presented to us today? Hawkins razor, suggests there must be a cause, to get the desired effect. Until we all get a straight answer to this question, they are just beating their gums. We all know it too. Why would anyone continue to pay their premium for 500K in life insurance, when neither you or your carrier can produce the original policy you just bought?

      • Dikran Marsupial

        Don’t be tiresome. Science is a search for the truth, whinging “but they do it too” is not a valid response to a scientific criticism, never has been, never will.

        If you can identify a statement made by Trenberth or Mann, where the support from the data is demonstrably not statistically significant, and that is the only evidence suggesting it is true, then do let me know and I’ll happily criticise them as well for that.

      • Nit pick ‘p’ eggs ’til you’re blue in the face, this pause has meaning. What is it?
        ===========

      • Global warming is pacing itself. A little break now and then is good.

      • simon abingdon

        “A little break now and then is good”. (As Mr Attlee might have said).

      • I ask for a physical meaning, not a moral one, M. carey. And when are you going to figure out that warming is better than cooling?
        ==========

      • Dikran Marsupial, Don’t be tiresome. Science is a search for the truth,
        Then you need to take the bag off of you head and find the originals. Let us all take a peek at what was written down by the weather man… next the scientific number given. AGW say: Hay that’s science today.

      • Dikran Marsupial

        O.K., so you don’t know of a specific example of Trenberth or Mann ignoring statistical significance either. Do let me know when one occurs to you and we can discuss it.

      • Easy. Trenberth chapter 3 AR4. where ge and co author Jones misrepresented McKitrick. McKitricks result was statistically significant. Trenberth made up facts with no cites and claimed the result wasnt significant.

        Climategate dude dont go there. you lose on this one.

      • Dikran Marsupial

        can you give me a page reference on that one?

      • Steven Mosher

        section 3.2.2.2

        Here is the quote.

        “McKitrick and Michaels (2004) and De Laat and Maurellis (2006) attempted to demonstrate that geographical patterns of warming trends over land are strongly correlated with geographical patterns of industrial and socioeconomic development, implying that urbanisation and related land surface changes have caused much of the observed warming. However, the locations of greatest socioeconomic development are also those that have been most warmed by atmospheric circulation changes (Sections 3.2.2.7 and 3.6.4), which exhibit large-scale coherence. Hence, the correlation of warming with industrial and socioeconomic development ceases to be statistically significant. ”

        Let’s start with some background that you do not know. In the climategate mails Jones ( co author of this chapter with trenberth) said that he would redefine peer review to keep MM04 ( reference here ) out of AR4. For the first draft or two he succeeded. McKittrick was a reviewer and asked MM04 was not being considered. When two papers MM04 and Delaat06 were brought up Trenberth and Jones consented to at least read the papers. Then they wrote this paragraph. In the inquiry into CRU the committee looked intoo this matter and because they could not decide who wrote these words, they dropped the matter.

        The sentence in question is this: “Hence, the correlation of warming with industrial and socioeconomic development ceases to be statistically significant. ”

        That is a conclusion that is not supported by any cited calculation. It is not supported by any literature published or in press or accepted at the time the senetnce was written. Neither Trenberth nor Jones did the computations to ascertain whether or not the effect McKittrick found was rendered “non significant”. They made it up. There is one way and one way only to prove that TrenberthJones established that McKittrick’s findings were rendered “non significant”

        Produce the paper that shows the calculation. You can’t because there is none. Go look high and low, you will not find it because it doesnt exist. They assumed but never proved that atmospheric circulation changes would render the result insignificant. It may. It may not. The proper way to address that is to write the paper and show it.

        After AR4 was published, of course, other attacked this problem.
        The issue is still undecided

        http://www.rossmckitrick.com/uploads/4/8/0/8/4808045/final_jesm_dec2010.formatted.

        So, produce the paper or show their calculation

      • Dikran Marsupial

        Steven, fair enough, Trenberth should either have given a reference to a work demonstrating that exact claim, or stated instead that the analysis of Michaels and McKitterick were invalid for the reasons given.

        Trenberth could perhaps have referenced this paper

        http://regclim.met.no/results/Benestad04_CR_c027p171.pdf

        which suggests that the M&M results were not robust anyway.

        Now I have answered your question, however given that you have seen fit to descend to childishness “Dikranaway”, it seems that you are just another of the blogsphere rhetoricians. Sorry I am interested in science, I am not interested in argument for the sake of it, life is too short,

      • Trenberths admission that the heat they need for their theory is missing. Mann’s hockey stick nonsense.

      • Dikran Marsupial

        O.K., so in both cases how should a test of statistical significance be performed?

      • Steven Mosher

        you first Dikran.

        I’ve provided an example above of trenberth failing to do the calculation. In AR4 no less. So first we start wiith your admission that the example exists. Then we know that we can reason together.

        First things first.

      • taps.. foot.

        Dikran, didnt you say on the other thread that scientists should answer direct questions directly?

        You’ve got one waiting for you above..

        find that calculation that Trenberth did to claim that MM04′s result was not significant? hmm? how did they rerun his model with different atmopsheric circulations? hmm? maybe they forgot to cite the paper that did this? hmm? Maybe they planned to never discuss the paper in AR4, redefining peer review, and maybe they just made up the “fact” that they thought the result lacked significance? hmm?

        When you’ve finished searching for the paper or the calculations that dont exist to backup the bogus claim, I predict you’ll say it doesnt matter. not that that question is the one I’ve asked, but you wont give a direct answer to a simple sentence as you suggested Judith should. will you

      • Dikran Marsupial | November 5, 2011 at 3:06 pm |
        O.K., so in both cases how should a test of statistical significance be performed?

        ————

        That is exactly what McIntyre did, and why Mann failed.

      • steven mosher

        Dikranaway

    • Torture the data on the rack of Procrustean significance. Do you think this ‘pause’ is insignificant?

      If so, why does it give pause to so many?
      ==================

      • Dikran Marsupial

        Because many are ignorant of statistics. This isn’t a criticism of them, most people don’t need to have a solid grasp of statistics in their daily lives and there is no reason why they should know statistics better than I should know (say) art history. However, that does mean that scientists such as Prof. Curry have a duty to make sure that their public statements have solid support from experiment and observation. Tests of statistical significance (flawed as they may be) are designed to make it more difficult to torture the data not less. If you ignore statistical significance there is much more you can torture them to say.

      • So, what value of ‘p’ is significant, and why? And what happens on either side of that rigid line? Significance is only narrowly defined in statistics, and that narrow definition is useful and limiting. Useful because it is limiting,

        But we’re trying to figure out the cause of the pause, and your requirement for narrowly defined significance is stopping up your ears, rather than filtering the signal from the noise.
        ==============

      • Dikran Marsupial

        alpha = 0.05 is the normal criterion adopted by tradition; however FIsher said that alpha should be chosen according to the nature of the problem. However the point is that statistical significance is a hurdle that you must pass before making a claim, so it LIMITS what you can claim is true based on the data you have. Thus it prevents torture of data.

        If you want to know the cause of the pause, I suspect you ought to have a look at the many analyses where the effects of ENSO have been subtracted from the global surface temperatures. This eliminates any evidence of any pause, which strongly suggests that the pause is probably due to ENSO (and thus is a redistribution of heat rather than a pause in warming). This shouldn’t be news to anyone who has actually looked into it.

      • The nature of the problem requires that significance not be denoted as a line in the sand, on one side of which stands truth and the other error.

        And sure, I think the pause is caused by the oceanic oscillations. What I’d like to know is how the sun drives the oscillations, and what a sun whose spots are disappearing before our eyes is going to wreak on Climate Earth.
        ============

      • Dikran sez “Because many are ignorant of statistics”

        You are going to have to show the statistical significance of that statement. After all, it’s our “duty to make sure that their public statements have solid support from experiment and observation”

      • Dikran, ignorance is a two edged concept. The mathematical fact is that there is no valid way to compute significance when the data is created via grid cell analysis or kringing. Treating high level aggregations as data points is invalid.

  57. Hi Judy – You write

    “IMO, the significance of the BEST data in terms of the temperature record of the past 50 years or so is that it puts to rest the concern that Phil Jones and Jim Hansen have “cooked” the land surface temperature data.”

    As you note there was never an issue with credible climate scientists that anyone has manipulated (cooked) the data to produce a pre-conceived trend. However, the BEST data only tells us something new if they cover significantly different geographic areas. I still have not seen an answer from anyone on this question.

    • Go north, young man. Track the ice bear to its lair. Note the Stevenson screen on the patio by the charcoal grill.
      =================

    • doskonaleszare

      > As you note there was never an issue with credible climate scientists that anyone has manipulated (cooked) the data to produce a pre-conceived trend.

      In the words of your recent co-author, Anthony Watts (“SURFACE TEMPERATURE RECORDS: POLICY DRIVEN DECEPTION?”):

      “Instrumental temperature data for the pre-satellite era (1850-1980) have been so widely, systematically, and unidirectionally tampered with that it cannot be credibly asserted there has been any significant “global warming” in the 20th century.”

      “Around 1990, NOAA began weeding out more than three-quarters of the climate measuring stations around the world. They may have been working under the auspices of the World Meteorological Organization (WMO). It can be shown that they systematically and purposefully, country by country, removed higher-latitude, higher-altitude and rural locations, all of which had a tendency to be cooler.”

      “The thermometers were marched towards the tropics, the sea, and airports near bigger cities. These data were then used to determine the global average temperature and to initialize climate models. Interestingly, the very same stations that have been deleted from the world climate network were retained for computing the average-temperature base periods, further increasing the bias towards overstatement of warming by NOAA.”

      • Looks like yet another over-generalization by a “skeptic” about the beliefs of other “skeptics.”

        Why does this happen so often?

        It’s almost as if they are deliberately “tampering” with perspectives in the debate, or perhaps “systematically, and purposefully,” mis-representing each others’ views.

        Why would they want to do that?

      • Joshua –

        ‘Why would THEY want to do that’

        It seems you have given up any pretence of distinguishing between ‘some’ and ‘all’ to make your repetitive and blinkered points.

        Do you not see the over-generalisations around you and within you made by alarmists about alarmists?

        I thought, for a few days, that you had finally slunk off with your bigoted tail between your legs. Seems not.

      • Anteros –

        You’re absolutely right I should say “some skeptics” all the time When I don’t I deserve to be called out.

        As of the whole “bigoted” charge – I’d love an explanation. The reason why I stopped posting on the topic is because apparently, unlike as we see in the comments of numerous “skeptics” mocking the tribalism of climate scientists, Judith objects to my mocking criticism of a prominent “skeptical” scientist’s blatant tribalism (comparing an environmental ethos to eugenics). She also used the double-standard explanation that my post was off-topic (when my posst was in response to other posts – that didn’t get deleted – directed at me, on a thread with multiple “off-topic” posts).

        Perhaps Judith will delete this response to you also (it is her blog, after all). Well, if not, I still fail to understand why mocking said scientist is considered bigotry or “anti-Semitism” — and would be curious as to the explanation.

      • next he’ll say we have horns

      • Little josh is back. His need for attention won out over his shame. Or is he just shameless?

      • steven -

        Still waiting for the explanation.

        The scientists whose name apparently must be unmentioned analogized environmentalists to eugenicists.

        How does pointing that out (and laughing at the extremism/absurdity of the analogy – especially coming from a climate scientists, a clear indication of tribalism) constitute antisemitism. A simple explanation would suffice. I’m really curious.

        And while you’re at it, why would Judith delete my comment asking you for an explanation and not your comment saying that my comment was antisemitic?

    • different times matter as well.
      also the bring in CRN which is helpful.

      So, before I tell you how they improve spatial coverage, what do you mean by significant

    • Hi Roger, actually they do have a plot that shows this. i’ve seen it elsewhere but here it is in muller and rohde’s presentations at santa fe, there is a fig about 2/3 down the file.

      http://berkeleyearth.org/Resources/BerkeleyEarthSantaFe.pdf

  58. Why do they show the global mean temperature pattern like this?

    http://bit.ly/hDTohi

    Why don’t they show it like this?

    http://bit.ly/v6RXQV

    It reminds me Pravda of the USSR!

  59. As far as the BEST PR coverage is concerned, let’s separate “fact” from “non-fact”.

    Anything that has been physically observed, measured and recorded is “fact”.

    Anything else is “non-fact” (or “fiction”, or “conjecture”)

    Question #1: Has the Earth been warming?

    As Judith writes: Addressing this question in a sensible way requires that a specific period be specified, presumably in the context of the increase in atmospheric CO2 concentrations.

    Climate historians like Tony Brown might say we should start looking in the 17th century, when first modern records were taken in Central England and elsewhere and the long-term warming started, as we were emerging from a colder period called the Little Ice Age.

    But for now, let’s start in 1850 with the longest global record, HadCRUT3.

    This record tells us that it has warmed by about 0.7°C since the record started. The BEST analysis confirms this rate of increase.

    This increase was not steady, but occurred in three multi-decadal warming cycles of around 30 years each with multi-decadal cycles of slight cooling of about the same length in between. These can be smoothed out a bit by using 10-year averages, etc., but the “fact” is that they are there.

    CO2 has risen from an estimated 290 ppmv in 1850 to a measured 390 ppmv today.

    This occurred slowly at first, but after around 1970 it increased at an exponential rate of 0.45% per year, and now appears to have leveled off to a linear rate of around 2.2 ppmv per year. There were no multi-decadal cycles as in the temperature record.

    Question #2: Is global warming over?

    The only “fact” we have here is that it appears to have stopped around the end of 2000, and has cooled slightly since then (at a cooling rate similar to the warming rate experienced from 1850 to 2000, or around –0.06°C per decade).

    We have no “facts” to tell us whether or not it is “over”, but most people believe that it will eventually start warming again, possibly at the same long-term rate already seen since 1850, and quite possibly with similar multi-decadal cycles of warming and slight cooling. Some others (including IPCC) postulate that it will resume at a much higher rate, with no future cooling cycles.

    Question #3: Has global warming stopped?

    We have no “facts” to answer this question; it has certainly “stopped” for now, but most people believe that it will resume and continue as before (see previous question).

    Question #4: Has there been a pause in the global warming?

    We can answer this question with “facts”. The answer is “yes” (see above). Anyone who denies this is simply sticking his head in the sand.

    Now we come to Question #5: What is going to happen in the future?

    Here we have no “facts” – just “conjecture”.

    Whether the conjecture comes from gazing into a crystal ball or from a computer model, it is still simply conjecture.

    No one knows what is going to happen in the future.

    Anyone who claims to predict future temperatures, from computer model simulations based on “solid physical theories” (for one piece of the puzzle) is bamboozling you.

    Max

    • I know what is going to happen in the future. The globe is going to get cooler and warmer, repetitively. What I can’t predict is whether or not we’ll get lucky enough to figure out why.
      ==================

    • How do you know the “fact” in your answers to 2, 3 and 4?

      From the BEST data, post 2000 warming still looks like +0.015 C/yr (or 0.15C/decade):

      Get and unzip http://www.berkeleyearth.org/downloads/analysis-data.zip Then, in R:

      x=read.table(comment=’%’,
      col.names=c(“year”,”anomaly”,”uncert”,”anom5yr”,”unc5yr”),
      “~/Downloads/analysis-data/Full_Database_Average_summary.txt”)

      > coef(lm(anomaly ~ year, x,subset=year>2000))
      (Intercept) year
      -29.77958333 0.01531667

    • Joachim Seifert

      Hi, Max,
      I am unhappy about the Warmist term: “Pause”, which implies that after
      a certain rest or break, the road upwards will then continue!
      A better word would be “standstill of warming”……thus more neutral……
      Better still: Plateau, because we are on the top level from where it can only go down……
      Your quote:
      ——”No one knows……nothing. what will happen…..” – that says the burrow in front of the wall clock”
      What we need is to comprehend is the “clock mechanism” and when
      you understand the mechanism of the clock, than you will understand time and you will be able to predict the future …..
      If you focus on statistics, i.e. the swing of the clock pendulum (left-right-left-right etc) you cannot derive conclusions on the inherent mechanism….useless….

      • Joachim Seifert

        Yes. The word “pause” does suggest that the warming trend will continue.

        This is the position of the IPCC “believers”.

        I would go with Girma on this one.

        His analysis is based on the concept that “history repeats itself”.

        Your basis is somewhat different, but comes out to a similar conclusion, if I understand it right.

        Girma’s analysis shows it will first cool a bit and then re-start warming as it has in the past, like a sine curve on a tilted axis.

        Whether or not a) human CO2 has had much to do with past warming or b) will be a principal driver of future warming are separate questions.

        I’d say that until a) can be answered definitively (see earlier “uncertainty monster” thread), we cannot answer b).

        But I would be interested in hearing more about your thoughts on this.

        Max

      • Joachim Seifert

        Hi Max,
        I feel that the community feels that they tinker around on the surface with minimalistic short term trends and that some major aspect remains still in the pipeline which, until today, has been completely overlooked…..
        And this truely is the case: Omit one major factor (variable, parameter … mechanism….as you like) in the input of hindsight and prediction models, as in all of them, ever since TAR, you will not and cannot have correct predictions……The missing forcing agent is the Libration forcing (see Wikipedia:Libration, with animated picture of the Moon) . By calculating this Libration forcing on a time scale, you will see, that global warming has stopped at 2000 and stays flat as Plateau for the next decades until 2043. This is indisputable and can be transparently followed by everyone interested…..

    • Max

      Now we come to Question #5: What is going to happen in the future?

      Here we have no “facts” – just “conjecture”.

      We have to accept what the global mean temperature pattern shows as=>

      http://bit.ly/uXy8jw

      Assuming the above pattern continues, the globe will cool by about 0.3 deg C by 2030.

      However, due to the persistent warming of 0.06 deg C per decade, the actual further cooling by 2030 should be about 0.3-0.06*2 = 0.2 deg C.

      So expect further cooling by about 0.2 deg C by 2030. Then further warming at the rate of 0.16 deg C per decade will resume until another peak by 2060, similar to the peaks in the 1880s, 1940s, & 2000s.

    • max – I never claimed a number of degrees per decade. The last two months in the BEST data are currently useless. BEST admits this. When the rest of the data is assembled, those two months will change radically to the hot side. Accept it now or accept it later. Don’t matter. One way or the other, it’s coming down your tube.

  60. Using MEAN temps gives a false rise. note that i used the MEAN temps in trend line yet used isolated points ins graphing..

    http://www.woodfortrees.org/plot/best/isolate:13/isolate:11/from:1976.5/plot/best/from:1976.5/trend/plot/best-lower/from:1976.5/trend/plot/best-upper/from:1976.5/trend/plot/best/from:1998/trend/plot/best-upper/from:1998/trend/plot/hadsst2gl/from:1976.5/trend/plot/best-lower/from:1998/trend/plot/hadsst2gl/mean:13/mean:11/from:1976.5

    when isolated temps are used there is little to no rise in global temp. but when MEANS are used it artificially increases the temp.. Huston we have a problem…

  61. The inestimable kim writes :”I ask for a physical meaning, not a moral one, M. carey. And when are you going to figure out that warming is better than cooling?”

    Amen to that. Even if the warmists are right, I’ll take my chances with a warmer world. Man will adapt just as he always has. In any case, it’s obvious this is much ado about nothing in a practical sense. We’re never going to undertake meaningful countermeasures because they’re far too onerous in a world drowning in debt. I’m a helluva lot more worried about Greece defaulting than I am about milder winters and hot summers.

    • Pokerguy, saying you will take your chances on a warmer world ain’t saying much, since it’s not likely to warm fast enough in your lifetime to be a problem for you.

      AGW skeptics and deniers are not adaptable. They panic at the thought of having to pay the cost of pollution now, rather than pass the expense to future generations. These energy hogs are big fat weenies.

      If you are worried about Greece defaulting, hedge against the consequences. If you are wrong, consider it money spent on insurance.

      No matter what you do, your capital is always at risk.

  62. Here is the GHCN v2 data set. The black diamonds are the annual anomalies, 1/100 of a degree. The red line is a sixth order polynomial and the black line is the integral of the fit, giving the rate. Polynomials are nice to give you the ‘cleanest’ information free fit, and are dead easy to transform.
    The average rate is 0.68 degree century.

    The waveform of the rate plot indicates at least one cycle of 60-70 years, peak to peak; with an underlying zero order process.

  63. DocMartyn, it looks like insiders started to ‘dump’ their stock in early 2000.

    • Some super-large investor has been shorting global temperature for the past 10 years and making a fortune in the process – is it George Soros?

      • Probably Al Gore.

      • Al’s just the sucker who drew the crowd.
        ==============

      • kim

        Al may be the sucker that drew the crowd, but he’s amassed a neat bundle with his global warming gig.

        Was he also the guy that organized the band of pickpockets circulating through the crowd?

        Max

      • I did it quick and clean. There appears to be a 60-70 years cyclic warm/cooling trend and a zero order constant background (little ice-age bounce?).
        The beauty of a polynomial is that it is hands off. I looked at the residuals (temp-fit) and essentially have information free noise. The rate crossed zero between 2008/2009; the rate fell below the mean rate, 0.6864 degrees century, for the 1880-2010 period in in07/08.
        Am now looking at the ocean indexes, which have a 60-70 year waveform.

      • Were he the least bit leveraged, he’s throwing snake’s eyes lately, and the pickpockets dip in vain.
        ===============

      • ‘Why knot’ Soros…

      • DocMartyn, I should have put a smile on my comment. I have looked at many stock charts in my time, what I see is the 50 day moving average as it crosses the 200 day moving average. When they cross, it is time to review your position. Your chart was very clear to me. As to George, well.

  64. ‘Why knot’ Soros:

    Well, Soros did pretty well by breaking the British Pound on “Black Wednesday” (16 September 1992) by selling it short with $10 billion (he netted over $2 billion in one day).

  65. “Note that the short time scales considered here preclude determination of a statistically significant trend at the 95% confidence level, although lack of statistical signficance does not negate the existence of a pause as defined here.”
    I have no evidence that any goats in my neighbors’ fields haven’t disappeared, and I have even more no evidence that these possible disappearances weren’t the work of la chupacabra.
    I suggest that a single sentence will do in response to the question about a pause, “There is not enough yearly data to say with confidence that global warming has paused since 1998.” This is pretty much what Muller said, except you can best him by not waffling on it. That statement is not only accurate and clear, it would prevent abuse by journalists like Rose or irresponsible bloggers in those circles you mentioned that attack the credibility of surface temperature record.

    If you make the claim that “Our data show the pause,” I would expect you as a scientist to be able and willing to back that up with your data, or at least something other than what amounts to “I can’t shown that there wasn’t a pause.” Especially so since you’re listed as coauthor on a paper which concludes the opposite (Berkeley Earth Averaging Process, p. 26). Rather than being enlightening on that point, this post has only been muddling.

      • First problem is that the faulty data from the last two months of 2010 aren’t dropped (They come exclusively from 47 stations situated around the Antarctic, compared to almost 1,500 globally-distributed stations for the previous months).
        The second problem is that this only looks at 10 years of data, which isn’t even as much as the 12 years that Dr. Curry used despite admitting the statistical meaninglessness of such noisy data over such a short time period. Dr. Whitehouse can try and head this argument off at the pass about using previous years as starting points by calling this “cherry picking” but that’s -nothing- compared to the slight-of-hand it takes to present this amount of data as if it were a meaningful representation of climate trends.
        Third, and tying into the second point, the trend line should have indications for standard error, meaning there is more room around that line where you can fit “valid” trends both above and below it. Within the space afforded by using two times the standard error you will be able to draw trend lines that are indistinguishable from previous recent decades, and they will be as “valid” as the “statistically flat” trend Dr. Whitehouse assures us is in this data. In fact you could go the other way and draw a trend line with a -decline- of similar magnitude and still fit it within the appropriate bands of error. This reinforces point 2, that the time span used here is too short to draw meaningful conclusions from.

        So I’m sorry, but this is not a convincing rebuttal at all. In fact it tends to engender the opposite of confidence regarding reliability.

      • Sorry, Wheels, your latest rationalization of why the (land-only) BEST record of the past 10 years shows no warming is meaningless (“well, it’s OK except for some of the data points…and, well, it should be representative for the other 70% of the globe that it has not measured”…duh!)..

        Get used to the fact that the observed global temperature has stopped warming for over 10 years now (Trenberth’s “travesty”).

        It should be good news for you, if you were once fretting about rampant global warming scorching the Earth, rising sea levels inundating your great-grandchildren’s Manhattan apartments or Florida houses and all the other horrible “deleterious effects” predicted by the doomsday prophets like James E. Hansen.

        If IPCC cannot predict the next 10 years, why should we have any faith in its prediction for the next 100 years?

        Obviously, we shouldn’t.

        Max

      • It’s disheartening to see you totally ignore the problems involved in using such short time spans. I cannot say this any more plainly: you Capital C Cannot state with confidence that warming has stopped from only this much data. This is not a “rationalization,” it’s a plain fact. There’s a reason science relies on things like 95% confidence intervals instead of the ol’ eyeball when looking at data.
        It’s also disheartening to see you brush aside the obviously unreliable nature of the data for 2010, even though there’s an easy fix for that (leave those months out, since we know it’s bad; wait for an update that includes more data).

        You’re also factually incorrect about Trenberth’s “travesty.” He never lamented that temperatures stopped rising, he lamented that we don’t have enough sensors throughout the planet (from orbit to the oceans) to monitor where all the energy goes all the time. It’s like an accountant complaining that their client isn’t tracking expenses like they should be; the account knows their income, knows how much money their clients have at the end of the month, but isn’t being given enough receipts to account for all the spending.

        As to being able to predict the next ten years, once again that’s wrong-headed. Short-term cyclical factors (ENSO, solar variability, etc.), noisy annual variation, and unpredictable factors like the precise amount of sulfates we’re going to emit or whether we’re going to have any large volcanic eruptions make predictions over very short time periods (like a decade) next to worthless. Over the long term, these factors are less important; cycles and year-to-year variation cancel out, volcanic eruptions are rare and so don’t push down the century’s temperatures as much compared to a decade’s, etc. What you’re saying is no different in character from arguing that a failure to predict the weather three days from now precludes any ability to predict the climate in 50 years. 10 years is still too much weather and not enough climate.
        That’s why climate is generally defined in terms of multiple decades of data, why Santer et al. find that you need at least 17 years of data to compare models and the real world, and why real scientists don’t say “OMG GLOBAL WARMING HAS STOPPED!” every time the temperature seems to drop or flatten for a handful of years.

        If you have a real counterargument to all this, please let me have it. But don’t dismiss these inconvenient facts as “rationalization” and proceed to matter-of-factly say things about the climate that the data can’t support.

      • Wheels:

        You’re also factually incorrect about Trenberth’s “travesty.” He never lamented that temperatures stopped rising…

        I think it’s you who’s being factually incorrect. Here’s Trenberth’s quote below (bolded by me) in context:

        Kevin Trenberth wrote:

        Hi all

        Well I have my own article on where the heck is global warming? We are asking that here in Boulder where we have broken records the past two days for the coldest days on record. We had 4 inches of snow. The high the last 2 days was below 30F and the normal is 69F, and it smashed the previous records for these days by 10F. The low was about 18F and also a record low, well below the previous record low. This is January weather (see the Rockies baseball playoff game was canceled on saturday and then played last night in below freezing weather).

        Trenberth, K. E., 2009: An imperative for climate change planning: tracking Earth’s global energy. /Current Opinion in Environmental Sustainability/, *1*, 19-27, doi:10.1016/j.cosust.2009.06.001. [PDF]
        (A PDF of the published version can be obtained from the author.)

        The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t. The CERES data published in the August BAMS 09 supplement on 2008 shows there should be even more warming: but the data are surely wrong. Our observing system is inadequate.

      • @Peter317:
        No, I’m afraid you’re misinterpreting that remark. The last sentence gives it away: “Our observing system is inadequate.”

        This, combined with the content of the paper he was announcing publication of, clearly indicate that he’s lamenting the gaps in our monitoring of the climate system to show where the energy is being sent if it’s not showing up in the surface/upper oceans/lower atmosphere records. This is the entire point of the paper, in fact. Here’s the abstract:
        “Planned adaptation to climate change requires information about what is happening and why. While a long-term trend is for global warming, short-term periods of cooling can occur and have physical causes associated with natural variability. However, such natural variability means that energy is rearranged or changed within the climate system, and should be traceable. An assessment is given of our ability to track changes in reservoirs and flows of energy within the climate system. Arguments are given that developing the ability to do this is important, as it affects interpretations of global and especially regional climate change, and prospects for the future.”

        … and reading the email message without that context makes it easy to mistake its meaning. But once you take ALL the information in the message together, it’s very clear and unambiguous. We can’t account for the lack of warming in the records because we weren’t able to track the energy as it traveled around the climate system. Just like you can’t balance your checkbook if you’re half-assing records of your expenses and deposits, if you’re missing parts of the planet where energy can hide (say, the deep oceans) you’re not going to be able to track changes in the energy budget accurately. Given how important the climate is to us, Trenberth thinks it’s a shame that we aren’t doing more to fill in those gaps with more sensor networks etc. His remark has nothing to do with hypothetical shortcomings of AGW theories, and everything to do with our apparent indifference to studying the climate system when ignorance can bite us.

        Does that clear it up?

      • @Wheels, I’m inclined to concede that point, but for the remarks of Wigley and Mann in response to Trenberth’s email – which don’t quite gel with what he’s trying to say (and he might be quite sincere in this, I’m not saying he isn’t)
        But another day…

    • Curry’s statement:

      Note that the short time scales considered here preclude determination of a statistically significant trend at the 95% confidence level, although lack of statistical signficance does not negate the existence of a pause as defined here

      is curious for what happens when one presents it thus:

      …short time scales… preclude determination of a statistically significant trend at the 95% confidence level, although lack of statistical signficance does not negate the existence of [warming] as defined here.

      Remember Phil Jones’ much lauded (by denialists) claim that there was “no warming since 1995“? Well, this is no different, except that Jones was prepared to use the convention and state explicitly that statistical significance was not achieved with 15 years, and therefore similarly prepared to not over-interpret data from short periods of time. The rephrasing of Curry in the preceding paragraph says exactly was Jones was saying.

      Tellingly, Jones also noted (but was not quoted by the denial movement) that the probability of the 15-year period showing a warming trend that refuted a null hypothesis was 0.94, and further that another year would likely increase to significance the power to discern signal from noise. I’m curious to know what p-value Curry has determined her approach might produce, and also what the 1-β value of any such analysis would be.

      Or to put it another way, compare and contrast…

      • Bernard J.

        Your point regarding “statistical significance” is well taken.

        Jones’ HadCRUT3 data show a slight cooling since January 2001.

        Is the cooling “statistically significant” (as a long-term “trend”?)

        Probably not.

        But it does show that the IPCC forecasts of 0.2C warming per decade (made both in the AR4 and previous TAR reports) were incorrect.

        And, by extension, if IPCC cannot get the next decade right, why should we believe that it can get the next nine decades right?

        Remember that, by definition, predictions are more difficult to make the longer the time period.

        Obviously, this is a dilemma for IPCC, whether you would like to accept it or not.

        Max

      • Let’s see what the IPCC actually said:
        “This analysis focuses on three periods over the coming century: an early-century period 2011 to 2030, a mid-century period 2046 to 2065 and the late-century period 2080 to 2099, all relative to the 1980 to 1999 means. The multi-model ensemble mean warmings for the three future periods in the different experiments are given in Table 10.5, among other results. The close agreement of warming for the early century, with a range of only 0.05°C among the SRES cases, shows that no matter which of these non-mitigation scenarios is followed, the warming is similar on the time scale of the next decade or two. Note that the precision given here is only relevant for comparison between these means. As evident in Figure 10.4 and discussed in Section 10.5, uncertainties in the projections are larger. ”

        http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-3-1.html

        Seems to me we’ve only just started to get into the time period covered by their ‘per decade’ projections this year (and that there’s some uncertainty associated with the amount of increase per decade that you’re not taking into account anyway). So looking at the period 2000-2010 isn’t relevant when talking about the amount of warming they’re projecting.
        I should also point out that there is a difference between a projection and a prediction, but given the short time scales here and the amount of warming “in the pipeline” already it’s probably not germane in this case. Just please don’t confuse the two.

  66. “Pokerguy, saying you will take your chances on a warmer world ain’t saying much, since it’s not likely to warm fast enough in your lifetime to be a problem for you.”

    I have grandchildren, the latest just 2 weeks old. That said, I think CAGW is the biggest scientific mistake (I’m being generous) in modern history.

    • pokerguy, CAGW is scientifically sound. The National Academy of Sciences is not an organization of fools.

      Please accept my apology for my rude characterization of deniers and skeptics in my previous post, and for implying you are motivated by a desire to waste energy. For all I know, you may be a CFL using Prius driver.

  67. Warming has obviously stopped for the 14 last years.

    Look at WfT.

    RSS data : trend = – 0,02°C per decade.
    HADCRUT3 : trend = 0
    UAH data : Trend = +0,06°C per decade

  68. That’s pretty good. In my mind I amplified a few of your points as I think you might have — your post is quite succinct, and could be elaborated into a 20 minute talk very readily. I think that a room full of statisticians would love to hear and see your presentation. :-)

    I think that a more fruitful approach, at least until another decade has passed, is to pick starting dates corresponding to explicit predictions, and see how the climate evolution compares to the prediction. There are dozens of these. The earliest that I know of was Hansen in 1988 — the disparity of prediction and outcome has led him to attribute the disparity to his use of a climate sensitivity estimate that was too high (I think he is a little consistent about this, sometimes making public statements as though the 1988 projection was accurate.) iirc (sadly, I have not catalogued all my reading) I read a projection in 1990 based purely on model fitting, and it came to a concluding that the temperature record would be pretty flat about now. Girma has presented us with similar projections, and if there is a date when she did her first, we could pick that date as the starting date of a sequential evaluation. Vukcevik has given us some of these as well.

    For each dated forecast, we can track the subsequent record, and use a suite of sequential statistical tests to determine whether at some point it is clear that the forecast is wrong at one of the respected levels of statistical significance.

    Alternatively, one could start with this year, and work backward using a technique like cusum, and see whether evidence accumulates to conclude that, by 1988 (say) the regime has changed.

    To repeat a comment that several have made, the 17-year lower bound on the duration to detect a change is quite reasonable. That makes now a really good time to start watching closely to determine whether a change was induced about 2000. 6 more years seems now like a long time, but it is a short time compared to the time required to introduce new technologies. By then, electricity from solar will be much more competitive against electricity from conventional sources, and biofuel will be a non-negligible fraction of the fuel used by the international airline industry (maybe), Iowa and Texas will have perhaps 3 times as many wind turbines as now — who knows, maybe there will be new watershed control projects completed or under construction in Thailand, the Mekong River, Queensland and upper .Amazonia. Maybe plug-in hybrids will be the dominant type of new car and lithium mines and rare-earth mines will have re-opened in Nevada and California. Whether 6 years is long or short depends on what you compare it to, but it does seem as though an answer to the main question can’t be supplied before then.

    • MattStat –

      We can pick on Hansen, but he is just one person. What about a summary of the whole field of climate science? How about the first such summary since we have the longest period of time to assess its predictions?

      So, IPCC 1990 says – BAU prediction of about 0.3 degrees C per decade. Uncertainty 0.2 -0.5.

      My contention is that a more accurate prediction would have come from moving the whole estimate to the left by 0.3 degrees. I.e a BAU prediction of 0 degrees, uncertainty -0.1 – +0.2 degrees. Strangely compelling even if made with hindsight.

      There are many reasons for the overestimation (the prediction was that BAU emissions which they underestimated would lead to a doubling of CO2 ppmv by 2025, which is verging on the insane)

      A more major contention of mine is that the whole field of climate science continues to overestimate such things as equilibrium climate sensitivity for reasons of psychology and sociology. See Milikan’s oil drop experiment for an exemplar of this and bear in mind the original Hansen estimate of 4.2 degrees. I think we know a lot more about people than we do about climate. Therefore I predict that the ESTMATE of CS will fall from its present 3 degrees +/- 50%. I offered ten of my English pounds for such a wager over at Keith Kloor’s and there were no takers. Publication of AR6 to be the due date.

      BTW I always thinks Hansen (and his followers) excuse that the only reason for his failed prediction was that climate sensitivity is lower than thought, is extraordinary. His estimate of climate sensitivity WAS his prediction. That he got it wrong WAS his failure – what else was he trying to do ? Bearing in mind he also (like the IPCC) underestimated the increase of emissions – >50% since 1990

      Sooner or later we have to own up to our gaffes and move on (as I might have to with AR6….. :) )

  69. Go back 300 years, the earth is warming. Go back 2000 it is cooling. Depending on where you start your analysis, there is no point on earth that is not both warming and cooling at the same time.

    BEST found that 1/3 of all sites are cooling. How about if they said 1/3 of all people are below average intelligence and 2/3 are average or above? Would you take that as proof that human beings were increasing in intelligence?

    It reminds me of the politicians trick:

    to get sympathy:
    “nearly 50% of XXX are living below average”

    to get praise say:
    “nearly 50% of XXX are now above average”

    • You are confusing median and average. If I have a set {3, 9, 9) my average is 7, so 1/3 of my set is below average and 2/3 are at or above the average.

  70. M. carey | November 5, 2011 at 2:05 pm | Reply
    They panic at the thought of having to pay the cost of pollution now, rather than pass the expense to future generations.

    Who do you think is going to pay the national debt? Cleaning up pollution by borrowing money is passing on the expense to future generations so that you don’t have to live with pollution today.

    If you want the benefits of clean air, no problem. Balance the budget so that the expense is not passed on to the future generations.

  71. I think our focus is being diverted.

    Did not the IPCC AR4 claim “accelerated warming”?

    http://bit.ly/b9eKXz

    Did not the IPCC stated confidence in near-term projections?

    Since IPCC’s first report in 1990, assessed projections have suggested global average temperature increases between about 0.15°C and 0.3°C per decade for 1990 to 2005. This can now be compared with observed values of about 0.2°C per decade, strengthening confidence in near-term projections.

    Here is the current status of global warming for the last 20 years=>

    http://bit.ly/rYp5OM

    What we need to focus is on the validity of near-term projections of the IPCC.

    How come no one in the scientific establishment says IPCC projections are wrong?

  72. And yet, adding on the WoodForTrees Temperature Index (which includes the 3 you have used, plus GISTEMP) gives a positive trend of 0.04C/Decade :

    http://www.woodfortrees.org/plot/rss/from:1997.7/plot/rss/from:1997.7/trend/plot/hadcrut3vgl/from:1997.7/plot/hadcrut3vgl/from:1997.7/trend/plot/uah/from:1997.7/plot/uah/from:1997.7/trend/plot/wti/from:1997.7/plot/wti/from:1997.7/trend

    More data which says a continuation of warming and certainly not a “stopping”, surely ?

  73. Paper on surface temps and recent warmings:

    http://mpmedia.xpr.ca/media/CBC%20Petition.pdf

    Abstract.

    We evaluate to what extent the temperature rise in the past 100 years was a trend or a natural fluctuation and analyze 2249 worldwide monthly temperature records from GISS (NASA) with the 100-year period covering 1906-2005 and the two 50-year periods from 1906 to 1955 and 1956 to 2005. No global records are applied. The data document a strong urban heat island eff ect (UHI) and a warming with increasing station elevation. For the period 1906-2005, we evaluate a global warming of 0.58°C as the mean for all records. This decreases to 0.41°C if restricted to stations with a population of less than 1000 and below 800 meter above sea level. About a quarter of all the records for the 100-year period show a fall in temperatures. Our hypothesis for the analysis is – as generally in the papers concerned with long-term persistence of temperature records – that the observed temperature records are a combination of long-term correlated records with an additional trend, which is caused for instance by anthropogenic CO2, the UHI or other forcings. We apply the detrended fluctuation analysis (DFA) and evaluate Hurst exponents between 0.6 and 0.65 for the majority of stations, which is in excellent agreement with the literature and use a method only recently published, which is based on DFA, synthetic records and Monte Carlo simulation. As a result, the probabilities that the observed temperature series are natural have values roughly between 40% and 90%, depending on the stations characteristics and the periods considered. ‘Natural’ means that we do not have within a defi ned con fidence interval a defi nitely positive anthropogenic contribution and, therefore, only a marginal anthropogenic contribution can not be excluded.

  74. My comment above should have been as a reply to Eric Ollivet above :

    http://judithcurry.com/2011/11/04/pause/#comment-133424

    (I have re-posted my comment in the correct place)

  75. Dr Curry, you sate “IMO, the significance of the BEST data in terms of the temperature record of the past 50 years or so is that it puts to rest the concern that Phil Jones and Jim Hansen have “cooked” the land surface temperature data. This has not been a serious concern among the people paying close attention to this issue and who actually read the journal publications and look at the actual data; but it is a concern in certain circles, and in the U.S. this concern has been raised by at least one Republican presidential candidate. The relatively small discrepancies between the BEST and the GISS and CRU data sets are of some interest; the apparent discrepancy with GISS has been resolved. Note: the CRU data set shows less warming than BEST over the past 15 years.”

    You must be JOKING.
    The Taverage data, which are temperatures not anomalies is absolutely riddled with errors, how can you use an error ridden dataset for accurate trend analysis?
    I scanned the data initially looking for patterns and it soon became apparent that the data has lots of improper minus signs causing data to vary by 30-40 degrees between months.
    Next I looked at Winter averages and found that they were higher than summer averages, how can this be.
    I ran simple query for all stations above 10 degrees latitude for January versus June, July & August and if it was higher than any one of them flag it up.
    Of the 34103 sites above 10d Latitude 30506 have 1 or more January averages higher than June, July or August, sometimes all 3 summer months.
    I found that of the 34103 sites above 10d Latitude 29770 have 1 or more with both January & February averages higher than June, July or August, sometimes all 3 summer months.
    This can’t possibly be correct, what has there processing done to the values?

  76. In the end the thing that worries me about this “pause” notion is that it carries with it the implication that in some well specified model of the way global temperatures behave that temp is a function of time.

    I could believe temp is a function previous temps, or a function of something that is correlated with time, but time itself – its hard to image.

    • There is only one nominally independent variable: it is the sun, stupid!

      • On what time scale was your model approximating the climate?

      • Indeed? Let us say that the average land based rate of volcanic discharge of dust is about 0.28 km3 per decade, but that there is a positive feedback along chains, so that one one goes, it causes a chain reaction. Thus, the patten, in an active area, tends to be 0,0,0,0,0, 1, 2, 4, 10, 40, 25, 10, 3, 2, 1, 0, 0, 0, 0.
        This would tend to produce cold spikes. Should you have clusters going off at the same time, you have a cold few decades, whereas a series of 00000000000 is a warm phase.
        This is also an independent variable.

      • BTW just noted some recent work that suggests large earthquakes may cluster in time in this way (at least within a related geological region).

        In this regard it did occur to me to suggest continental drift as another independent variable, but didn’t feel it was quite in the spirit of the comment being made by Wagathon.

      • Sun is not an independent variable, not according to results shown here:

        http://www.vukcevic.talktalk.net/LFC2.htm

  77. This is all getting a bit silly.

    You can get the data to show you anything you want with the application of certain statistical methods.

    Don’t have the time now, but get the data pre industrial revolution, plot it, get the post data, plot it. Apply linear regression and compare the slopes.

    The post data will need a much larger error limit, given the shortness of the data set, but this test should tell you all you need to know. UNless of couirse the climate is cyclical, in which case any sort of linear trend is wholly misleading.

    HOnestly, only in climate science.

  78. Skeptics have a bit of a blind spot when it comes to the sun as an explanation of the pause. After the super El Nino f 1998 we went into a solar maximum by 2000 which only diminished to a minimum around 2009, and started to come out of it in 2010. The solar irradiance dropped enough to explain a temperature drop of about 0.1 degrees globally, yet skeptics prefer to remain focused on the CO2 rise. This convergence of El Nino and solar effects has unfortunately confused many and is exactly the reason that temperature changes over a decade are not very meaningful in climate prediction.

    • “he solar irradiance dropped enough to explain a temperature drop of about 0.1 degrees globally”
      You think we all believe in a ‘climate sensitivity’ control knob?

      • I used to think most people thought that the sun had an effect on climate, but I seem to be mistaken when it comes to skeptics, at least when it is not convenient for them. I merely draw their attention to something to think about regarding pertinent factors to this issue.

      • This convergence of El Nino and solar effects has unfortunately confused many and is exactly the reason that temperature changes over a decade are not very meaningful in climate prediction.

        There is another subtle effect. Clearly the atmospheric levels of methane have leveled off the last 10 years.

        Methane is a potent GHG but it only has 1/4 to 1/3 the temperature forcing of CO2, so it may act to modulate the rise. Since it has a much shorter residence time than CO2, the effects of methane are more immediate, and it won’t show the long-term inertia of CO2.

        Of course, the underlying concern is that natural methane could start to emerge from its permafrost lair if things start to heat up too much.

      • you are not the only one to notice the same skeptics who like to cry “it’s the sun stupid” are very reluctant to factor in the impact of the recent solar minimum on temperatures.

      • Well, at least they’re inconsistent.

    • The IPCC’s “scenarios” couldn’t figure out that the sun is on an 11 year cycle? Odd that they still claimed ~0.2 deg/decade, given that you claim a 0.1 deg drop from the solar cycle should be obvious to everyone.

      And speaking of blind spots, weren’t we told in 1998 that global warming was the cause of that super El Nino?

      Kind of cheeky to now claim that the “pause” is because of a lack of another strong El Nino.

      • We see these pauses to some extent in every solar cycle if you remove high-frequency signals like El Nino. Also it makes no sense to start a time series at a super El Nino, as that has a bias built in. I think I am just stating the obvious here.

      • …and ignoring the previous claims about “super El Ninos”.

      • El Ninos come from the ocean circulation, not CO2. It is an additive effect that causes more recent El Ninos to be warmer and La Ninas to be less cool than those in previous decades. Maybe that is what you read about in this connection.

      • Yes, only a poor little dumb skeptic like me would try to link stronger El Ninos to ghgs.

        These changes are qualitatively consistent with those expected from increased greenhouse gases in the atmosphere.

        http://www.cgd.ucar.edu/cas/Trenberth/trenberth.papers/PDSI-GRL-98-Paper.pdf

        Odd that such broad claims would be made on the basis of a 20 year period, starting in the late 70s, you know, when the PDO last shifted. Hey, but only skeptics choose selective starting points, eh?

        And back to the 1998 El Nino:

        The El Ninos have become increasingly severe and frequent through the 1980s and 1990, leading to suggestions that they are being affected by global warming, caused by an increase in heat-trapping greenhouse gases in the upper atmosphere.

        http://www.ips.fi/koulut/199802/2.htm

        One more:

        “So instead of having cool water periods for a year or two, we’ll have El Nino upon El Nino, and that will become the norm. And you’ll have an El Nino, that instead of lasting 18 months, lasts 18 years,”

        http://news.bbc.co.uk/2/hi/science/nature/25433.stm

        As I said, to now claim the “pause” is because of no more really strong El Ninos is pretty cheeky.

      • John M, so you think the hypothesized increased frequency of El Ninos should already have started in this decade we just had? This is typical of skeptics being too impatient for the big changes to happen on shorter time scales than the scientists say they will.

      • Jim D,

        I’m saying climate scientists were saying the changes had already started in 1998.

        Whatever may or may not be typical of skeptics can’t erase what is in the record. And I might say that what they were saying in 1998 is typical of climate scientists (and there supporters) jumping on whatever’s in the news and trying to make hay with it.

      • Trenberth is well known for his method of using current extreme events as teaching moments for things that might be more common in the future due to AGW, which is effective, but they do not apply to decadal trends.

      • I guess one man’s “teaching moment” is another man’s sophistry.

        Null hypotheses are such ephermeral things.

      • “Also it makes no sense to start a time series at a super El Nino”

        From a denialist’s POV it does!

      • Jim D – makes no sense, but let them. On GisTemp and BEST land, which does have something to say about global, there is still a positive trend.

        It’s one year to BEST land and ocean, which may well end HadCrut’s being used deceptively in this silly game.

        If Smith et al is right, it’s three years to slam dunking these folks.

      • And if not in 3 years? Is the AGW faithful slam dunked?

      • It’s one year to BEST land and ocean, which may well end HadCrut’s being used deceptively in this silly game.

        Does that mean the IPCC will then base all of its conclusions on the BEST data instead of HadCrut? You know, all those model “hindcasts” that were validated based on HadCrut and all the proxy studies that were calibrated on HadCrut. Will they all need to be redone using BEST data?

        It’ll be interesting to see the song and dance used to explain the strong 19th century warming shown by BEST. I wonder if the aerosol pixie dust will have to be rescaled based on BEST too.

      • JCH

        On GisTemp and BEST land, which does have something to say about global, there is still a positive trend

        Let’s forget GISTemp (the odd man out, run by an advocate,who predicted that there would be a positive trend – duh!)

        But BEST shows that the warming has stalled (over land, at least):

        http://thegwpf.org/the-observatory/4230-best-confirms-global-temperature-standstill.html

        Max

        PS Even Trenberth has conceded this “unexplained travesty” – are you still one of the lonely deniers left out there? Pull your head out of the sand and accept the data as they are.

      • John M | November 5, 2011 at 6:29 pm |
        It’ll be interesting to see the song and dance used to explain the strong 19th century warming shown by BEST. I wonder if the aerosol pixie dust will have to be rescaled based on BEST too.

        ———-

        Not from me you wont. I don’t deny the evidence. I challenge the CAUSE. Watch the song and dance when I demand that the AGW show that CO2 emissions is the cause of this warming.

      • Richard,

        The song and dance I’m anticipating will be coming from the “consensus” side. Of course all that pre-supposes the BEST method actually survives peer-review.

      • Yes, skeptics usually care about the sun and statistics, but in this case they seem to be found lacking on both fronts. Is a trend biased if you start with a maximum? Why aren’t they being skeptical here?

      • If we observe the solar cycle on the t series in the SH the first observation is the appearance of spikes in the ascending phase.

        http://www.woodfortrees.org/plot/hadcrut3sh/from:1970/mean:4/every:4/to:2010/plot/hadcrut3sh/from:1970/to:1980/trend/plot/hadcrut3sh/from:1980/to:1990/trend/plot/hadcrut3sh/from:1990/to:2000/trend

        /plot/hadcrut3sh/from:2000/to:2010/trend/plot/pmod/from:1970/normalise

        Normalised to see if information is topologically relevent.So do we remove all Elnino excursions or not seems to be the pertinent question.

        BTW the problematic issue with instruments is not addressed in the PMOD data as suggested by Svalgaard and which has been confirmed.ie the amplitude of the solar minimum 22/23 is deeper then used in recent models eg lean 2011,Hansen 2011.The get out of jail card is cancelled. eg Krivova 2011.

        These results suggest that early degradation trends in PMO6V data (Fr¨ohlich, 2000; Fr¨ohlich & Finsterle, 2001) might have not been fully accounted for (cf. also Frohlich, 2009). For this reason, the level of TSI during the activity minimum in 1996 seems to be overestimated in the PMOD composite by roughly 0.2 W/m2, which explains the apparently different behaviour of the TSI over cycle 23 when compared to other
        proxies as found by Fr¨ohlich (2009). Therefore we conclude
        that the TSI variability in cycle 23 is fully consistent with the
        solar surface magnetism mechanism

    • Jim D, skeptics are trying to falsify CO2GW! Of course they’re focused on the CO2 rise! Regarding solar, most sceptics are focused on the solar variation between the 11-year cycles and not on the irradiance variation between minima and maxima of the single cycles. For instance, sc 21 and 22 were short cycles (strong) and they caused the late 20th century warming. Sc 23 was long (weak) and that caused the pause. Sc 24 seems to be even weaker, so cooling is ahead.

      • Exactly, they don’t realize how important the solar variation is in the period of the pause itself. If they want to focus on this sub-decadal variation, they have to consider the sun equally or any argument is worthless.

      • JD, google ‘Livingston and Penn’ and then please try to explain large, sparse and primarily southern hemispheric sunspots during the Maunder Minimum.
        ================

      • It’s not the TSI, though, it’s something else; what it is even kim doesn’t know.
        ==============

      • Wait for the next solar max before judging this as a ‘pause’.

      • It’s not the TSI. Doesn’t vary enough to explain climate variation.
        ============

      • Yet variations of up to 0.2 C occur in phase with the solar cycle. TSI or GCRs, it doesn’t matter which you prefer, something happens.

      • Yes, and the climate varies more than 0.2 degrees Centigrade. I am talking about millenial scale variation in the sun, presently unknown, and you are talking about eleven year cycles.
        =====================

      • Since this thread is about decadal scales, those few tenths of a degree become very important here.

      • Your apple will fall to the ground and then jump back in the tree every eleven years, while my orange has gone pale.
        ===================

      • I think we agree that sub-decadal trends have nothing to do with century climate forecasts, and this whole topic is a sideshow.

      • KIM,

        TSI is a “static number” given the fusion reaction on the sun. what it fails to show is the effect of magnetic waves on the earth and its systems. One is solar wind which directly affects Cosmic radiation which affects the earths cloud cover. this secondary system of magnetic waves either allows the radiation to enter the earths atmosphere and ionize water into clouds or it pushes them away reducing that interaction.

        there so much we still do not understand about how the gravitational and magnetic waves affect our earth and its complex systems.

        Blowing off the sun is a bad thing to do….

      • It’s the balance. This is kinda like watching a slow motion train wreck. CO2 radiant is overestimate, solar underestimated, natural variability underestimated, conductive influence of carbonic acid not even considered. Solar atmosphere/surface absorption ratio not seriously considered. The sum of several third and fourth order effects are overtaking a second to third order effect.

        But, they are confident we need to do something now, even though that something may be the wrong thing.

      • dallas, you nailed it.

        My take is that it’s the wrong thing for sure, to try to do something. The talk is empty and no real CO2 emission reductions will be achieved, even if we all agree. It’s just bureaucratic verbiage. How much has Kyoto reduced global CO2 emissions? How much is that in °C? Anybody knows?

      • dallas and Edim

        There have been NO actionable proposals made to date for slowing global temperature increase by reducing CO2 emissions that make any sense at all.

        The very few specific proposals that have been made range from ridiculous to absurd to incredibly stupid.

        Max

      • Edim, You should look at some of the Arctic and Antarctic surface energy budget attempts. One had DWLR underestimated by 30Wm-2, but the surface temperature was too low. Tail wagging the dog, this DWLR fixation.

  79. The thing I keep coming back to is just how much energy….and pure stubborn will…it takes these days to be an informed true believer. Failed predictions left and right, missing heat, an ever increasing body of scientific literature supportive of the skeptical case….and these guys have to find a way to ignore or rationalize all of it.

    It must be exhausting.

  80. Ten years in Earths climate is less than a blink of an eye. Climate is never static, it never has been never will be. Fifty years from now it may be a a degree cooler or it may be a degree warmer, no one here can say for certain one way or the other. Myself I would bet on warming, but not because of anything man will do or not do. It’s simply that we are still a bit on the cool side historically.

  81. “It’s simply that we are still a bit on the cool side historically. ”

    Do you have a scientific reference for this assertion?

    • Oh, that’s easy. The last 200,000 years of earth history has been an iceage. Unprecidented in all of the previous 400 million years. Throughout the geological record winters are a rarity.

      • Oh, that’s easy. The last 200,000 years of earth history has been an iceage. Unprecidented in all of the previous 400 million years. Throughout the geological record winters are a rarity.

        So why do you believe in what paleoclimatologists say? Aren’t they scientists too? Cherry-pick data, cherry-pick science, no difference to the ignorant.

        I suppose you think that the Vostok ice core data is all screwed up.

      • I don’t believe anything anyone says. Unlike the AGW faithful, I look at the evidence, not what someone claims. The geological evidence is clear. Are you implying that the Arctic was the same 55myo as it is now? I never said the ice core data was screwed up. Greenland’s ice core data is only 200,000 years old. Antarctic was completely ice free 3 million years ago. A very short period of geological history.

      • I don’t believe anything anyone says.

        I kind of suspect that is true because you said “The last 200,000 years of earth history has been an iceage” with such certainty. All you have to do is bring up the Vostok data and see how that is wrong.

        This is worse than cherry-picking, this is just making stuff up.

        Wakefield, I remember when you got banned from http://TheOilDrum.com for all the anti-AGW comments you made. For a bunch of realists like the PO crowd, this nonsense does get tiresome.

      • @webby

        Perhaps you;d like to issue us with a list of the approved climate-related works that we are allowed to believe. Together with a list of those we must ignore. Then there can be no accusations of cherry-picking.

        In case you’d have any trouble giving the banned list a name, I’m sure the pope would give dispensation to let you borrow from his gig:

        ‘Index Librorum Prohibitorum’ has nice catchy feel about it. And such a good historic provenance as well.

        http://en.wikipedia.org/wiki/Index_Librorum_Prohibitorum.

        While we’re on the subject of historical provenance, are we still permitted to read contemporary records showing a warm spell in medieval times? Or have the subsequent publications by Mikey Mann and his Mates shown them all to be a denier conspiracy created by backward time travel to discredit a fine and honourable scientist?

        I just need to know exactly what the correct interpretation is today. Sorry if this is a difficult question. Please guide me.
        Cheers.

      • I’m afraid we can’t dismantle the quality controls that distinguish between real science and pseudoscience.

        Would those be the same quality controls that found little or no fault with the widepread and unrepentant fraud revealed in Climategate ?

      • @Robert

        None of the above Your Worship. As there is such a lot of climate-related literature and some of it is consensus approved texts and some are not, I just wanted a list of which ones us ordinary mortals are permitted to read.

        Because without the guidance of the clever climatologists here we might fall into error or heresy by reading unpermitted texts. Or history. Or lead us into asking awkward questions that the clever guys have difficulty in answering.

        And that would never do.

        But while we’re here, can you briefly outline the ‘quality controls’ that climatology goes through? Because it seems from my perspective that as long as you can find two mates to look at your work for ten minutes and anonymously sign (without any possibility of subsequent comeback) that it isn’t complete balderdash, then that is the entire QC regime completed.

        Which doesn’t seem very rigorous to me. I worked a lot in industries where QC was taken seriously – both because it was a good thing to do and because you go to jail if it isn’t. And to describe climatology as laughably inadequate by comparison would be an understatement.

      • Would those be the same quality controls that found little or no fault with the widepread and unrepentant fraud revealed in Climategate ?

        Thanks for illustrating a key point of the conspiracy theory mindset: the failure of “the establishment” to believe in your half-baked delusions (like “unrepentant fraud” or “Climategate”) is then used as evidence of their untrustworthiness.

        With perfect circularity, you then reject the evidence falsifying your fantasies because it comes from people who don’t believe in your other fantasies.

        You see the same cognitive fallacy at work in Birtherism, vaccine denial, belief in “chronic Lyme disease,” etc., etc.

        You are interesting as a classic presentation of self-delusion, but you’re not doing your credibility any favors.

      • Robert
        Climategate uncontrovertably showed widespead hiding of data, attempts to pervert peer review, etc. Your denial of these obvious realities places you firmly in fantasyland. And it is precisely this sort of refusal to criticise these frauds, that lowers the credibility of climate science.

      • None of the above Your Worship.

        It’s interesting to me that without my claiming any authority at all . . . just by talking about real science . . . Latimer is compelled to label me an opressive authority (“Your Worship.”) It underscores how, for scientifically ignorant deniers, reality itself seems tyrannical and oppressive. Merely speaking up for scientific fact is hateful because it denies Latimer the ability to simply invent a story he wishes were true.

        Of course no one is trying to deny Latimer the right to compose and distribute his fantasies. The conflict arises when he demands that these fantasies be placed on an equal footing with science, and that he, without going to the trouble of understanding the science, be considered an authority on the matter.

        Science is science, Latimer. It’s about the evidence. Why not call your thing, where you make up what you wish were true, something else, and stop trying to interject it into the world of rationality?

      • I wish Dr Curry would ban you, Robert. Your posts are usually off topic and are so incredibly boring. This thread had been a pleasure to read until you pitched up again.

      • Oh, keep him. It’s like Old Home Week. We skeptics used to get treated like that all the time, and I’m missing it a little.

        Robert’s got an automatic election to the True Believer’s Hall of Fame.
        ================

      • @robert

        Aw shucks. You just don’t understand my cute English sense of humour. We use a form of words called ‘irony’ a lot. Simply put, it is when we say one thing to emphasise the exact opposite meaning.

        So If I were to refer to you a person as ‘His Excellency’ in an ironic tone, it would mean that I felt that said individual was anything but excellent. I know that this sometimes doesn’t travel well across the pond.

        Did I miss your essay on Quality Control in climatology? I think you were going to be able to explain how Phil Jones – according to his testimony before Parliament – has published over 200 papers in 30 odd years and nobody has ever asked to see his data or his working. In 200 papers. To my mind, this doesn’t tell a tale of an indepth and robust QC culture flowing through every pore of the field. But I’m not a climatologist – I did a hard science, so maybe you can put me right on the standards expected for its senior practitioners.. Toodle pip

    • there are literally thousands of references if one does a bit of research. Just specify your timeline. Here is a graph of fairly recent temperature changes. Notice the Minoan and Roman warm periods

      http://www.clivar.org/publications/other_pubs/clivar_transp/pdf_files/lb_pag2_992.pdf – this is from Von Grafenstein et al (1998)

      check the temperature throughout the Cenezoic, we have been cooling for the last 65 million years or so and are probably a good 2 degrees cooler than we were even 10 million years ago.

      We really need to stop thinking in decades and centuries here, the Earth has been warming and cooling since time began. There is still no definite answer for the Younger Dryas since the meteorite has been ruled out and the sudden freshwater influx hypothesis has some gaping holes in it, no pun intended.

  82. I saw Tamino’s post claiming that the Best data show the same trend after 1998 as before. I think he is being misleading here, because the average after 1998 is below the 1998 value.

    • You should expect the average after a high outlier to be less than the outlier. That
      is what makes it an outlier, and it will be true for any time series with a random component. So no, there’s nothing misleading about analyzing the trends in this case.

    • …And, 1998 was one h-ll of an outlier. It was head-and-shoulders above any previous year! People like to make a big deal out of the fact that, according to HADCRUT, the 1998 record has not yet been surpassed. However, the fact is that only 3 years since 1998 have not surpassed the pre-1998 record…and two of those were in the two years immediately following 1998. And, if you look at the pre-1997 record, it looks like every single year since 1997 has surpassed it!

      The whole argument for a “pause” basically rest on the data from one year…1998 (as well as looking at trends over short time periods without bothering to compute the uncertainty). It is just bad science.

      • Maybe you can hide it?

      • The whole argument for a “pause” basically rest on the data from one year…1998 (as well as looking at trends over short time periods without bothering to compute the uncertainty). It is just bad science.

        Worse, it is bad statistics masquerading as science, turning what passes for the science into a numerology side show. I think that is the intent, as all that matters is to convey FUD.

    • What was your start date?

  83. Stephen Wilde

    “the absence of an hypothesis that is related to a physical mechanism.”

    There is such a hypothesis.

    An active sun gives more zonal jets and/or more poleward climate zones with less global cloudiness and more energy into the oceans for gradually strengthening El Ninos as compared to La Ninas and a gradual rise in global tropospheric temperatures.

    The opposite when the sun is less active.

    Keep it simple.

    • BRAVO!….

      as Ive heard another say “its the sun stupid”

    • The sun does have its role. A little more to it. The climate shift seems to have started around 1994. You can see it in the mid trop versus strat data and it is pretty obvious in the ACE hurricane energy data. I can’t find a global Tmin data set, but it should be in there too starting in the southern hemisphere. How that matches the solar, I don’t know, haven’t looked.

      The Tmin data when UHI is properly corrected should clearly show the change in the radiant and conductive/convective impacts. Maybe Girma should start plotting that :)

  84. Stephen Wilde

    If the surface pressure distribution begins to shift to a more meridional/equatorward pattern as it did around 2000 then if previously it was in a poleward/zonal mode it is clear that warming will have ceased and cooling has begun due to more global cloudiness and less solar energy getting into the oceans.

    The regional implications are clear. Each region will get more weather characteristic of the climate zone which has moved closer to it.

    The largest changes will occur in the parts of the mid latitudes which find themselves more often on a different side of the mid latitude jes from the side they were more often on previously.

    Large changes will also be observed for areas that shift in or out of arid or semi arid zones.

    Or closer to or further from the ITCZ.

    So unless the air circulation becomes more zonal/poleward again we will continue to see more incursions of both polar and equatorial air masses into the mid latitudes (with the greater extremes that implies) but with a generally cooling trend.

    Regional seasonal trends can be readily discerned from that proposition subject only to shorter term chaotic variability.

    Thus a less active sun gives colder winters and cooler wetter summers in Western Europe simply because a less active sun gives more meridional/equatorward mid latitutude jets. Each region around the world will be affected in a slightly different way depending on its change in position relative to the nearest climate zone.

  85. So, we have a longer trend with high statistical significance, and a more recent, shorter trend with low statistical significance.

    What is the justification for saying anything about the longer trend?

    Yeah, it has long been known that short-term variances can overwhelm the longer term CO2 signal. So? If you trust short-term trends, you would conclude that global warming has been over about half a dozen times so far.

    • Are you refering to human caused global warming, that short period from 1975 to 1998, or the over all natural warming that has been happening since the end of the Little Ice Age?

      • There was a slight decline in temperature over the last several thousand years, up until humans started using fossil fuels, and since then there has been a rise. But, don’t let reality disturb your comforting thoughts.

  86. JC

    I have a request.

    Could you please, please, please, please insert the following graph (not just the link) just below this post’s title of “Pause(?)” as it answers all the questions you raised?

    http://bit.ly/rYp5OM

  87. Alex Heyworth

    Has global warming stopped?

    Global warming almost certainly stops many times a day. I think the question is not sufficiently specified.

  88. The question isn’t really whether the warming has stopped or even whether it has paused. A more intelligent question would be if the pattern of warming has recently changed. We’ve had 6 stops, or pauses if you prefer, in the last 40 years , so is the latest one any different from the previous 5?

    Without wishing to get into a convoluted argument about statistical significance, I’d just make the point that it doesn’t look like it.

    However, we should be due for another temperature jump in the next few years. Will we see one? That will be interesting.

  89. Those of you who want to calculate the trend of a profile after a peak by selecting a starting point before the peak must understand that you are not calculating the slope of the profile but the slope of the tunnel that starts from one side of the peak and comes out on the other side of the peak as shown in the following sketch.

    http://bit.ly/tFA8Qj

    The correct way to calculate a trend after the peak is to start from the peak as shown.

    • But if the long term trend is a sine wave, the over all trend is flat across several cycles. 1975- 1989 is just part of one cycle. The frequency of the cycle is some 1000 years long.

      • Yes.

        But are not we discussing at the short-term trend here?

      • Short term trend is meaningless when the frequency is long term. It’s like claiming a pendulum with a 1 minute frequency will keep rising forever because you are only looking at the first 2 seconds of the rise.

      • Joachim Seifert

        Rich: To longterm-shortterm trend.

        First of all: Why should a trend be a STRAIGHT line? Why can a longterm-trend not be stepwise-staircase like (see the old HadCRUT2 used to 2005) or saw-tooth-like or increase-followed by Plateau-like?
        The real trend is: Increase/decrease followed by plateau a.s.f. stepwise! This you would never detect by straightline trend, which are produced by Wood-for-trees-graphics, which in this blog always come up…..
        With a straightline trend, you may detect the tipping point into a plateau of the year 2001 only after many decades and if you are one of them straightliners, you will be convinced of it not before the year 2030….you will be the stubborn late learner….. but all here we are the ones, AHEAD of our times, otherwise it would be all just timewasting……
        JS

      • Latimer Alder

        @joachim

        Do the models predict such a stepwise trend? If so, which ones did so? How many do not? And when did they make the prediction?

        How long will the ‘plateau’ last?

      • JS, the real world, especially climate, never follows a straight line. Straight lines are our interpretations. The climate system is likely various cycles within cycles of various frequencies. Any attempt to predict the future based on a 30 year period (climate scientists claim is all they need, absurd) or our puny recordkeeping (100 years maybe), is futile. I love these AGW faithful who claim to be claravoyant by saying this pause is temporary and in a few years will take off rising again. I’d like for them to make heavy bets on that with real money. Then watch the backpeddling. Prophecy is cheap.

  90. Which prediction is more realistic?

    http://bit.ly/tFA8Qj

    The trend that starts before the peak or that starts at the peak?

  91. So the least fit for 1998 to 2009 is about .024 per year according to the BEST data.
    How much of an outlier can 1998 be when it has been beaten several times after that in the BEST data? The next 11 years show 2 years much higher, 3 much lower, and 5 near it in value.

  92. “Now listen closely, consensus defenders, because I know how the obvious facts go right over your heads…
    “This result also flies in the face of those [that includes you, Mr. Pratt] who would say the clouds of Venus reflect much of the incident solar energy, and that therefore it cannot get 1.91 times the power per unit area received by the Earth — the direct evidence presented here is that its atmosphere does, in fact, get that amount of power, remarkably closely.”

    Then, for the benefit of the lay reader, who would not be expected to understand the clear (to a competent physical scientist) implication of this simply-stated fact, I wrote: “This in fact indicates that the Venusian atmosphere is heated mainly by incident infrared [not the VISIBLE portion, which is indeed largely reflected, defenders, but INFRARED] radiation from the Sun, WHICH IS NOT REFLECTED BUT ABSORBED [or allowed in to heat the lower atmosphere] by Venus’s clouds, rather than by warming first of the planetary surface. (It also indicates that the Earth atmosphere is substantially warmed the same way, during daylight hours, by direct solar infrared irradiation…)” ”

    So one could say there is one difference between Earth and Venus in that sunlight doesn’t significantly directly warm the Venus surface. And your “Earth atmosphere is substantially warmed the same way” could allow for this- meaning earth is much same as venus other than a factor earth having surface warming. But a large part of earth warming is due to infrared spectrum [the adsorbed portion- as indicated, here:

    Or with Venus the only significant warming is done is the energy absorbed by atmosphere. And I suppose the other radiant energy leaves Venus at speed of light, though may bounce around bit before departing, but this doesn’t add significant heat.

  93. Over at the Blackboard, an article by Zeke presents a bar chart comparing 1979-2009 land surface temperature trends in degrees of rise per decade from a number of organizations. As best as I can tell from the bar chart, the trends are:

    BEST………………………. 0.28
    NCDC …………………….. 0.28
    GISS (land mask) …….. 0.27
    CruTemp (sa vg) ……… 0.26
    RSS land ………………… 0.20
    UAH land ………………… 0.16

    The bar chart also presents the results of independent work by several individuals.

    http://rankexploits.com/musings/

    • You know, I think I inspired some of that. I kept asking about Muller’s comment about CRU being an outlier, which I found to be the single interesting thing said in the entire Judy-Richard drama . I finally asked at Stoat, and a fellow said BEST made a mistake. At first I thought it would be impossible that a group of non-climate scientists would make a mistake as they’re purportedly better scientists, but there was something about the way he said it they it that made me think he knew what he was talking about (no spittle, climategate-free, rage-free, etc.), so I tipped it to the guys at Nick’s blog, and they took that part from there.

      I still don’t know if BEST made a mistake, but CRU is not an outlier there, just terribly chilly.

      • I still think you need to do weighted least squares for BEST and CRUTEM3 (savg), since they are given with stated uncertainties.

        Without including the weighting (“unweighted least squares”) I get:

        BEST: 0.279 °C/decade
        CRUTEM (savg): 0.268 °C/decade

        (It actually looks like Zeke made a roundoff error here.)

        WITH the weightings included… the so-called “weighted least squares fit”: They become:

        BEST: 0.344 °C/decade
        CRUTEM (savg): 0.266 °C/decade

        As far as I can tell, the biggest difference with BEST is that months that have large excursions tend to have the largest uncertainties (so these outliers get downweighted when you do a weighted least squares).

        In case anybody wonders the two fits to BEST both look “reasonable” plotted against the data.

  94. Just on a point of information: ‘exponential growth’ means that the rate of increase is proportional to total size.

    That’s true. It turns out that emissions growth is not exponential but more like a power-law. A power-law can accelerate fairly quickly but it does not sustain like an exponential growth will.

  95. The billion-dollar question about the pause is why did it happen like this?

    http://bit.ly/rvL1W5

    Instead of like this?

    http://bit.ly/b9eKXz

      • Girma

        Could you relate the CI for your trend lines to us?

        Do you understand what a confidence interval is?

        Because I don’t see a billion dollars worth of anything in your graphs.

        Or a dollar’s worth, either.

        If we’re taking Dr. Curry’s definition of pause at face value, you aren’t actually showing it on your graphs.

        Here:

        http://woodfortrees.org/plot/best-upper/from:1998/trend:11/plot/best/from:1981/trend/plot/best-lower/from:1981/trend/plot/best-upper/from:1981/trend/plot/best/from:1998/trend/plot/best-lower/from:1998/trend/plot/best/from:1981/to:1998/trend/plot/best-lower/from:1981/to:1998/trend/plot/best-upper/from:1981/to:1998/trend

        Note we’re using BEST land area, so actual rates of warming are slightly elevated from global levels including sea surface temperatures, however BEST has enough resolution to allow us to work with 12.5 years of temperature data and not have such abysmal CI as to need to reject the comparisons outright.. which would be a problem for HadCRU below 17 year spans.

        The trend prior to 1998 and the trend after 1998 are both slightly lower than the overall trend including both spans. This would hold true if we included sea temperatures, but would also lower our CI substantially.

        Further, looking at the overlapping 95% CI areas of each of the shorter spans with the longer span, we see very similar ratios of overlap with non-overlapping area for each span on BEST.

        There’s poor evidence for a pause on Dr. Curry’s terms, not just based on my quibble that it’s uncommon phrasing to pause something that hasn’t yet begun, but also because on BEST the pace of temperature rise is not demonstrably slowing, though it’s clear there could be a delay to reach the high rate of temperature rise predicted by an IPCC spokesperson, if SST is included from a reliable source.. but it’s premature to say.

      • Bart R

        “Pause?”

        n 1. a temporary stop or rest, esp in speech or action; short break

        Seems to fit (so far).

        After all, 11 years is a “short break” in the overall scheme of things.

        If it were to continue for another 5 or 6 years it would no longer be considered a “short break” (according to the wizards of climatology), but would become a “statistically significant trend”.

        So let’s see what happens.

        But let’s not delude ourselves into thinking it isn’t happening.

        That would be sticking the head in the sand.

        Max

      • Joachim Seifert

        To Max:
        Do you refer to Trenberths 17 years of fingerprint – interview?
        Can this number: “Another 6 years” – for being “statistically significant” seen in other statistical papers? Lubos Motl “The reference frame” calculates another 10 years……
        Clear is, (see my book) the temps have reached their max. Plateau and cannot/will not rise any further, because it is impossible…..
        Considering that, in only 6 more years we will be in a better argument’s position and meanwhile, have to defend science against AGW-BS…..

        In any case, time is on our side, which on the long run means, we will be the winner of history, although at the moment, AGW screems us down or
        ignores us…… lets hold out 6 more years and the dices will fall different:
        Interesting enough: scientific AGW-papers were already voluntarily withdrawn from publishing at the highest rate ever (!!!) and even “Nature”
        talks about the good value of “pre peer reviewed papers”, which do not have to pass AGW “gatekeeping”…….amazing what will happen in the course toward these 6 more required years until the fingerprint has been laid to rest…..
        JS

      • manacker

        There is no so to far. Stop doesn’t precede start. Rest doesn’t come before work.

        Please, by all means, show me on any global temperature record including SST the two decades or more that rose 0.17C/decade+ at 95% CI, preceding the supposed pause also at 95% CI.

        I’m not saying there won’t be one, however there isn’t one now, and there isn’t — based on past behaviors — even scant indication there might be one involving the current date.

        If the previous 95% CI trend to the 1998 date was only about as steep as the current 80% or lower CI trend, and both of those within a steeper cumulative temperature rise, then the argument of a pause now is no stronger than the argument of a pause from 1981-1998, which has been disproven by waiting not just another 5 or 6 years, but another 12.5 years (remembering BEST on WFT is only to 2010.5).

        Since every year in the 1970+ period has had people talking about the warming stopping or pausing or resting or on hiatus or slowing or cooling, we can adequately by hindsight apply the test you say is valid, waiting 5 or 6 years, and making the comparison every year up to 1993.. and oh look! They were wrong 24 times in a row, often on stronger evidence than you now claim now is a pause!

        You’re already deluding yourself into believing your evidence is more competent than it is, that it says the opposite of what logic tells us, and that you can treat greater Uncertainty as a form of greater certainty.

        That’s some sand, Max.

  96. Judith,

    It may be slightly off topic but I can’t see where else to post this.

    I notice that Gavin received an award recently. He is the recipient of the inaugural AGU Climate Communication Prize for his efforts at Realclimate.

    http://www.agu.org/news/press/pr_archives/2011/2011-34.shtml

    I thought perhaps you’d missed it and would like to add your congratulations. It’s the done thing, you know. It sounds like sour grapes if you say nothing at all !

  97. Some light but OFF-TOPIC questions for Judith :

    What textbooks and readings would (do?) you prescribe for first-year climatology students ?

    (And do you regard “climate science” and “climatology” as completely interchangeable?).

  98. Girma and MikeN

    According to the HadCRUT3 surface record, which is the one preferred by IPCC:
    - 1990s warmed at a rate of 0.18C per decade
    - 2000s cooled at a rate of 0.06C per decade

    http://www.woodfortrees.org/plot/hadcrut3vgl/from:1991/to:2000/plot/hadcrut3vgl/from:1991/to:2000/trend/plot/hadcrut3vgl/from:2001/to:2011/plot/hadcrut3vgl/from:2001/to:2011/trend

    Denialist arguments used to counter these observed facts:

    - Yeah. But the 2000s were “warmer on average” than the 1990s (so it must still be warming).

    Duh! Look at the graph.

    - But, hey, how about some other record, like GISS?

    Tell it to IPCC, who cite HadCRUT3.

    - Yeah, but, if we start at 2000 (or 1999) we show warming.

    So what?

    Get over it, folks.

    There has been a “pause” in the warming (as Judith has described it).

    Learn to accept it and live with it. It’s not the end of the world.

    In fact, it should be good news for those who are seriously worried about human-induced global warming, because it occurred despite the fact that CO2 levels were reaching record levels at the same time.

    Rejoice!

    Max.

      • Fixed a bit more:

        http://www.woodfortrees.org/plot/best/from:1991/to:2000/plot/best/from:1991/to:2000/trend/plot/best/from:2000/to:2010.2/plot/best/from:2000/to:2005/trend/plot/best/from:2005/to:2010/trend

        Hey, this is fun. We can play this game all day, if you like.

        Moral of the story: you can put your start points and end points wherever you like, and the trend line changes. What does that tell you?

      • Actually, the moral is: people who live by the trend line die by the trend line ;-)

      • It tells me that claims of “cooling” or “temperature flattening” are unrobust, ie shaky and not to be taken seriously when they fall apart at the whim of changing the start or end points slightly.

      • Give that man a cigar!

        So one can also say with justification, as our host has, that it also works the other way.

      • Latimer Alder

        Tells me that despite the game of statistical pattacake going on, there is no discernible trend in temperature (up or down) over the last ten or so years.

        So my personal level of concern about global warming is reduced yet further and is rapidly approaching zero. I just hope we don’t get the third bad (by our standards) UK winter in a row.

        But I also see some commentators here apparently desperate for the previous gentle upward trend in temperature to have continued.

        How very strange that those who are most frightened of the warming’s effects spend so much effort trying to ‘prove’ that it hasn’t gone away. With Kyoto coming to an end, surely they should be rejoicing at how effective it has been rather than trying to show that all their huffing and puffing and pontificating has been entirely pointless.

        Strange times indeed……. ;-)

      • Because Latimer some of us know that CO2 at the current rate of rise has a large warming effect and we also realize short-term periods are insufficient to determine the trends and therefore there’s no reason to assume the longterm warming has ended.

      • You do realize your paintball starts during a La Nina and ends during an El Nino?

      • lolwot:

        …some of us know that CO2 at the current rate of rise has a large warming effect

        Shouldn’t the bolded word be replaced with ‘hypothesise’?

        …short-term periods are insufficient to determine the trends and therefore there’s no reason to assume the longterm warming has ended.

        Just as they’re equally insufficient to show that the longterm warming hasn’t ended, or paused, as our host has been valiantly trying to point out.

      • JCH, ***splat!*** :-)
        But, in case you didn’t get my point, you can’t assert anything from trend lines, (especially short-term ones) because they are extremely sensitive
        to which side is doing the cherry-picking.
        They just serve to muddy the waters.

      • If AGW is so firm. If there is a looming catastrophy from rising temps, then there should be no question of whether or not the last 10 years is rising. The fact that it is NOT definatively rising like the 1975-1998 period means there is more going on in the climate system than just CO2 emissions, which have clearly risen during the last 10 years. AGW theory did not predict this, thus the fact that there is no way of knowing what the temperature is doing means AGW has a serious problem. If AGW was correct, the last 10 years would be definiatively rising. It’s not.

      • If AGW was correct, the last 10 years would be definitively rising.

        No, not ncessarily. It is still possible for other, natural forces be acting so as to cool, and thus offsetting AGW.

      • Joachim Seifert

        ——If WAG were correct, the temperature 2001-2011 would have been risen…….”not necessarily……..???

        Answer: The TAR SRES scenarios of 2000, with all their combined computer simulation power, of joint efforts from 40 famous climate institutes, made their Millenium forecasts 2000-2100 to triumph over the ignorant skeptics to AGW and push them out of the way by applying their combined wisdom………
        Such enormous knowledge of TAR (40 Institutes) must have produced at least 1 smallish paper, showing the present temp.plateau 2001-2011……
        Show me just one please of the 40 which forecasted correctly 2001-2011….

        You know better then me: “Not necessarily….?”.
        JS

      • Tells me that despite the game of statistical pattacake going on, there is no discernible trend in temperature (up or down) over the last ten or so years.

        So my personal level of concern about global warming is reduced yet further and is rapidly approaching zero. I just hope we don’t get the third bad (by our standards) UK winter in a row.

        But I also see some commentators here apparently desperate for the previous gentle upward trend in temperature to have continued.

        Not that at all, just trying to deduce or infer what is actually happening.

        I came up with an interesting analogy that relates to tsunamis. Before a tsunami hits shore, there is a precursor stage where it looks like the sea is appearing to retreat. Of course, we see the videos and watch people wander into the receding area while everyone with some knowledge is running for the hills.

        This is of course stretching an analogy but the point is that what you see and try to intuit is not always the way things turn out.

        The other aspect pertains to the nature of noise and fluctuation phenomena in itself. I received an early appreciation in my own education when I took a course from a pioneer in the field, van der Ziel. Noise is not just a statistical phenomena and there are many underlying explanations that shouldn’t be ignored.

      • Peter317

        Wow.

        The desperation of confirmation bias.

        FIVE year trend lines?

        FIVE?!

        Ludicrous.

        Might as well use trend lines from September to January of the same year in the Northern Hemisphere.

        You can play your game all day if you want, but if you make up rules and ignore the out-of-bounds lines and move the goalposts, everyone watching your game is going to know the quality of your unsporting character and just refuse to play with you.

        Either stick to trend lines with some semblence of an above 50% confidence interval on a timespan that itself covers at least a 95% CI (this isn’t so hard; it’s only 17 years), or compare enough trend lines of the length you choose to establish a 95% CI for the whole (for 5 years, you’ll need about 60 years) and then apply Bayesian analysis to determine how likely it is you’ve found the pause you claim given the downward trends you see.

        Which would give you a predicate probability of under five percent that there is a pause in the actual (not the IPCC projected 2.0C/century), and a not dissimilarly low probability there is a Curry Pause, too.

        I leave the details as an exercise to the reader.

      • Bart R, you missed my point by miles.
        Next time, try to ensure you have things in context before shooting your mouth off.

      • Peter317

        Your point? This point in this context?

        But, in case you didn’t get my point, you can’t assert anything from trend lines, (especially short-term ones) because they are extremely sensitive to which side is doing the cherry-picking.
        They just serve to muddy the waters.

        I get your point. It’s just wrong on fact.

        Trend lines are not “sensitive to which side is doing the cherry-picking.”

        It is possible to select trend lines without cherry-picking. If you really think I’ve cherry-picked, by all means point me to the graph you’re suspicious of, and I’ll be glad to detail the valid methodological rationale for my selections.

        If not cherry-picked — which is hard to do for sufficient timespans, though I’ll grant your point about short timespans — then not sensitive; if not sensitive nor cherry-picked, then one can only assert on the graph what the evidence indicates.. well, you do have something of a point there, I’ve seen manacker and others (on both sides) asserting the opposite of what the graphs say.

        But that can’t be blamed on the trend lines.

        That’s just plain inability to read a graph.

      • Bart R, if you go back to the start of this conversation: http://judithcurry.com/2011/11/04/pause/#comment-133692
        you’ll see that my first posting was meant as a somewhat sarcastic reply to the exchange between lolwot and edim, with the intent of showing them how ridiculous their arguments were getting.
        It was not meant to criticise any of your graphs – in fact, I’m not aware of any of your graphs just off the top of my head.
        Perhaps you should brush that chip off your shoulder, before it sticks.

      • lolwot

        Fixed that for you:
        It tells me that claims are unrobust, ie shaky and not to be taken seriously when they fall apart at the whim of changing the start or end points slightly on spans too short to have a significant confidence interval.

        Peter317
        Fixed yours too:
        Moral of the story: on spans too short to have a significant confidence interval you can put your start points and end points wherever you like, and the trend line changes.

        Latimer
        Fixing yours took a bit more work:
        there may be no discernible, or otherwise misleading, trends in temperature (up or down) over ten or so year spans where they are too short to have a significant confidence interval.

        The solution to all your problems?

        On HadCRU, don’t use trend lines shorter than 17 years.

        On BEST’s last half century, it appears slightly shorter trend lines may be reliable, but below 10 years is still just noise.

      • Bart R:

        there may be no discernible, or otherwise misleading, trends in temperature (up or down) over ten or so year spans where they are too short to have a significant confidence interval.

        What did you think I was trying to say all along? You simply can’t say whether or not it was warming or cooling (or whatever) on the strength of a 10-year trend line, which they were apparently trying to do. Why are you making waves about it? If you’re going to misrepresent me at every turn then I have no interest in continuing this discussion.

      • Peter317

        What did you think I was trying to say all along? You simply can’t say whether or not it was warming or cooling (or whatever) on the strength of a 10-year trend line, which they were apparently trying to do. Why are you making waves about it?

        I’m making waves because your conclusion isn’t exactly what the facts indicate.

        You conclude that both arguments were trying to draw a conclusion about warming or cooling on a 10-year trendline. When I do it, my argument in response to too-short trendlines sometimes is to supply alternative trendlines for exactly the same period that show the opposite sign, as proof by counterexample to indicate the specific trendline suggested is invalid; sometimes to supply long-enough trendlines when such are available, to illustrate a more correct method; sometimes to apply a methodologically valid use of short trendlines within a framework of a longer timespan and suggest the appropriate Bayesian treatment to predict the very low likelihood of the true trend being actually cooling given the too short trendline.

        None of these three is identical to your “throw up your hands and call it a draw” conclusion, nor are they anything remotely like the specious reasoning that claims, “well if it were real, it would be obvious on 10 years,” that frequently hangs out in the same bad neighborhood at the crossroads of Error and Illogic.

        On any timespan in the dataset, if you choose short enough samples, you will produce many, many trendlines of contradictory sign and rate. If your longer timespan itself is long enough, and your analyses of the short trendlines competent, you can (so long as the short spans are not too short) get robust answers about whether the present short trendline indicates a change from the longer term present trendline.

        The answer on the current 10-year trendline is, “No evidence of change from the 17-year trendline.”

        This is a standard statistical approach, and it puts the lie to your statements that nothing can be concluded.

        What can be concluded is that the present 10-year warming is more than 95% likely to be at least as great as the prior 17-year or even the current 30-year (slightly higher) period, nineteen times in twenty.

      • Punksta,

        Blimey! Your comment of November 6, 2011 at 9:20 am makes perfect sense!

        Maybe there is hope for you yet!

      • Don’t sell yourself short, Tempterrain, the credit is all down to you, for heroic efforts in extracting that enalrged skull of yours from your nether cavity.

      • Bart R: let’s just leave it at that, huh? I’m getting a bit tired of you putting words in my mouth.

    • Max

      They are telling us not to believe our lying eyes!

      They say the following is not a pause!

      http://bit.ly/rYp5OM

      I say it is a “decline”!

      • Girma

        You’re right.

        It looks like a “decline” to me, as well.

        But some may prefer to call it a “pause” (implying that it is sure to reverse very soon – maybe)..

        Others will stick their heads in the sand and simply say it doesn’t exist.

        DAGW “consensus” believers apparently do not like your analyses, because they are based on actual observations of past climate trends rather than on model predictions of future climate changes, which myopically fixate on the human-induced aspect only.

        Max

    • Latimer Alder

      @lolwot

      But even if you are right about long-term trends, it is short term stuff – a decade or so – that is being discussed here.

      Why the huge concern and data torturing to try to demonstrate a positive trend? Why would it matter so much to you if the consensus were that it is zero?

      Because the difference between it and zero is so small that arguing about it is ‘angels on the head of a pin’ stuff. To all practical purposes it is zero. Get over it. You will not persuade people that 0.006C per decade – or whatever minuscule trend you think you can detect – is anything to worry about. Not even with ‘drowning’ polar bears. Their knockers will remain pleasantly dry and trying to flog that particular dead horse gets you nowhere.

      And on the positive side, we have bought ourselves a further ten years plus for mature and considered reflection on what we need to do about this ‘problem’..if indeed there is one. We are no ‘worse off’ now than we were in 1998.

      Win win.

  99. Dear Dr Curry
    You say that the BEST analysis shows that CRU did not cook the books. That’s fine but please can you confirm that the global temperatures used by BEST were the original temperature readings from all the stations and not the readings homonigised by CRU.

    • that’s already been confirmed

    • Now it might be time to go ask all those prominent “skeptics” how come their supposed proof that Hansen and Jones had cooked the books didn’t turn out to be true.

      Take this one for example:

      http://joannenova.com.au/2010/03/the-mystery-deepens-where-did-that-decline-go/

      “When did the “funny business” begin? By 1980 Hansen and GISS had already produced graphs which were starting to neutralize the decline. His graphs of 1987 and then 2007 further reduced the decline, until the cooling from 1960 to 1975 was completely lost.”

      Yet if this was true BEST would have revealed the deeper cooling in the 1970s that Hansen had “neutralized”. Yet BEST agreed with GISTEMP over the 1970s

      And this is also another example of skeptics arguing the warming hadn’t happened. Precisely what skeptics try to pretend now they were never saying.

      • Silly you. By surface stations they actually meant the stations on the surface of the ocean. The photographs of the land stations were just a ruse to make Hansen they weren’t on to him. Just you wait until BEST completes the oceans.

      • JCH,

        I’ll ask again, will IPCC then use BEST to redo all of its previous work?

        Explaining that 19th century warming shown by BEST ought to be a hoot.

      • I do not know what the IPCC will do. But HadCrut may have a problem, and if it does, things will have to change, won’t they?

        I believe BEST is saying as they go back in time, the better HadCrut does. There may be an obvious reason for that.

      • Doesn’t BEST show a lot more 19th century warming than HadCrut does?

      • It will be interesting to see what happens when the oceans are included. I expect it to lower the temperature and the trend. What do you expect it to do?

        http://home.earthlink.net/~ponderthemaunder/id38.html

      • It will be interesting to see what happens when the oceans are included. I expect it to lower the temperature and the trend. What do you expect it to do?

        http://home.earthlink.net/~ponderthemaunder/id38.html

        Hey, it’s a link to the climate science website run by the delinquent teenager that Canadian raspberry lady was writing about!

      • I can’t say anything about the website since I yesterday was the first time I have visited it. I know the graph and this is where I happened to find a copy. My questions at RC also went unanswered when I asked why it was no longer there and I was asking before climategate. So I guess my response to where I found the graph is if it was still being posted at the GISS website I would have linked that ;)

      • So, there was no Cooling in the 60 & 70s.
        Do you not know how to read papers & historical documents?
        Or do you think that all those people and scientists just imagined it?

  100. lolwot
    You turn a blind eye to the undeniable systemic dishonesty in the climate establishment, as revealed in Climategate – both on the part of proven active miscreants like Jones and Mann, the attempted coverups by their employers, and the deafening silence on the topic from most of their professional fellows.

    That is the basis of most scepticsm. And what riles you so; you would it seems prefer that everyone just accept without question what these proven science crooks have to say. Well that just isn’t going to happen. Until the profession expels or punishes the Climategate crooks, it will continue to be seen by thinking people as an unreliable witness.

    • You turn a blind eye to the undeniable systemic dishonesty in the climate establishment, as revealed in Climategate . . .

      What are you referring to? The email theft that failed to turn up any evidence of dishonesty whatsoever?

      The “Climategate” myth has long since joined the “faked-moon-landing” myth and the “9/11-inside-job” myth as a meaningless canard that marks the conspiracy theorist as one in denial of reality.

    • It is Climategate denialism such as you espouse that ranks along with the faked moon landing as myth. Jones et al were clearly shown to be hiding data, manipulating the review process etc etc. Had he and others been promptly sacked as they so richly deserve, mainstream climate scientists might today not be regarded as cheap frauds as they now are.

  101. I was comparing BEST with GHCN v2 and found something odd.
    I created cumulative anomaly plot; adding annual anomaly from 1981 to 2010, of both BEST and GHCN v2 and then looked at the difference.

    Man made global warming appears to consist of adding noise and 1 degree per century to a temperature data-set

  102. “Note that the short time scales considered here preclude determination of a statistically significant trend at the 95% confidence level, although lack of statistical signficance does not negate the existence of a pause as defined here.”

    “Statistical analyses of various data sets over various periods aren’t all that interesting in the absence of an hypothesis that is related to a physical mechanism.”

    -
    Dr. Curry, some candid, crucial advice offered cordially…

    ‘Expert’ online climate discussion participants such as yourself and Leif Svalgaard need to brush up on Simpson’s Paradox.

    The primary conceptual bottleneck at this stage in the online natural climate variability discussion is in the area of spatiotemporal sampling & aggregation theory, not “mysterious unknown” physics.

    “On comprend, mais cela équivaut à chercher ses clefs au pied d’un réverbère parce que c’est là qu’il ya de la lumière.”

    http://www.pensee-unique.fr/theses.html#lod

    Google Translation:
    “It is understandable, but it is like looking for his keys at the foot of a street lamp because that’s where there’s light.”

    I’m again offering this fundamental advice with genuine sincerity and absolute confidence.

    • Re spatiotemporal sampling & aggregation theory, , considering this in the context of the spatio temporal chaos of the coupled nonlinear ocean atmosphere system will give you much richer insights than statistics alone. Svalgaard may be talking about missing physics/forcing, but I am basically talking about spatiotemporal chaos, which also happens to be physics (nonlinear dynamics).

      • Some here & probably many at WUWT have me pegged as a statistician, but I’m a hybrid (engineering, biology, ecology, math, stats, forestry, physical geography).

        Spatiotemporal aliasing (taking the form of actual physical leveraging) is evident in multidecadal terrestrial summaries. EOP (Earth Orientation Parameters) inform us that the alleged “spatiotemporal chaos” is spatiotemporally constrained.

        Careful data exploration & diagnostics are prerequisite to meaningful statistical inference & physical modeling, but untenable geometric modeling & inference assumptions are being made unconsciously since central-mainstream data exploration has overlooked fundamental spatiotemporal paradoxes.

        Until the models can recreate EOP, they ignore very simple asymmetries. This is something that should be quite easy for the climate science community to work out in collaboration with the EOP community. Crucial guidance appears almost certainly needed from other fields that have been through a sampling & aggregation awaking, such as some branches of advanced physical geography & landscape ecology. (There’s a major cross-disciplinary communication breakdown here.)

        Although I’m having doubts about the utility of blogs for efficiently discussing natural variability, I remain keen to contribute to serious cross-disciplinary collaborations if & when the time becomes ripe.

        http://wattsupwiththat.com/2011/10/15/shifting-sun-earth-moon-harmonies-beats-biases/#comment-769231

        http://wattsupwiththat.files.wordpress.com/2011/10/vaughn-sun-earth-moon-harmonies-beats-biases.pdf

        Regards.

    • I’m again offering this fundamental advice with genuine sincerity and absolute confidence.

      “Google Translation:” The fantasy above is brought to you courtesy of the Dunning–Kruger effect.

      • Parfait. Gentil. Good night.
        ==================

      • Simpson’s Paradox is real.

      • Sound studios are real. It doesn’t mean they were used to fake the moon landings.

        Most crackpot theories are not simply made up out of nothing. If someone doubts your belief in the Loch Ness monster, “Loch Ness is a real place” is not a counterargument.

        I advise you not to waste your time and ours seeking refuge from reality in allusions to things you don’t understand.

  103. So now it is settled…CO2 has nothing to do with AGW…this wonderful, magical life-giving compound has been abused and its virtues were distorted but now we can all celebrate it`s survival and revival. So who do we go after next? Water vapor will be the natural choice and all those nuclear plants spewing out all that pollution will be the new culprit. But how do we make money off this?

    • Joachim Seifert

      Latimer,
      the accurate Plateau-forecast you can find in the (German) Amazon.de:
      ISBN 978-3-86805-604-4, which shows that global temps continue for 3-4 decades as Plateau and will decline thereafter. Temps cannot rise higher than the plateau…….
      This was crystal clear to me since 2006 and I am in the fifth year of being correct…….forget CO2 completely…..
      The underlying longterm trend is Earth’s orbit “Libration” (please see Wikipedia, animated picture for the Moon) and you will see that variations in the distance Earth-Sun along the generally known orbit are the cause of the underlying trend…….this is transparently for everybody demonstated with clear calculations …….
      The AGW fraction is feared stiff and not even dares to touch the book
      for in case the truth comes out to fast……

      • Joachim

        You mean “http://en.wikipedia.org/wiki/Libration” ?

        So, we are getting closer to the sun, eh? Congratulations! You seem to have come up with a new theory. I’ll have to let skepticalscience know about that one.

        Maybe I should reserve judgement until we’ve seen your “clear calculations” which are “transparently for everybody demonstated ….” Is it something to do with a sudden increase in the world’s population at the end of the 20th century? The extra weight is causing an increased gravitational force between the earth and the sun and it’s pulling us in closer?

      • Joachim Seifert

        Tempterrain,
        can you please stop your jokes if you do not know what you are talking about…. The Earth’s orbit is worth looking into…..the real flight trajectory is not the orbit line, which is in your head and in your
        simplistic imagination, but rather does pendulum swings around this
        line, which lengthens or shortens the distance to the Sun, thus producing more or less RF….producing higher or lower global temps….
        Its not my fault if your level of astronomical knowledge is at rock bottom….

        JS

  104. Dr Curry -

    Though in some of your posts there has been communication back and forth, I see no communication going on here in this one. My guess is that with the BEST study the warmers have jumped to the conclusion that it is all over and their side has won, so they have no interest in any rational discussion – just pushing the same old assertions and expecting everyone to start accepting them like good little fundamentalists.

    But they don’t even realize – or hear – that BEST did not, in Dr Muller’s own words “what portion human activity contributed.” The warmers all believe that CO2>warming was somehow proven with BEST. Their confirmation bias is intact, and not to the benefit of the discussion or the future of all of this. And even though BEST’s intentions were to address the questions raised by skeptics, the warmers don’t get it: The science was not settled.

    The discussion of all of this should have taken place back in the late 1980s and early 1990s. All the uncertainties and ambiguities should have been addressed – not to mention to ACTUALLY falsify alternative forcings other than CO2. All discussion then was shut off, which put us where we are now. There were so many things that weren’t even known about then or included in the discussion at that time (PDO, AMO, cosmic rays, etc.), yet we are to believe that the “settled science” of 1990 was exactly the same as now. They knew it all then, to hear them tell it, but obviously they didn’t, not if all that was not even on the horizon. Al the time since then it has been them shoving CO2>warming down our throats, and it is still that way. Nothing has changed except for the hardening of the lines. BEST is taken for something it is not, and the skeptics have to bear the brunt of their misplaced hubris. They act – again – as if it is all over but the shouting. Sounds like 1990 all over again.

  105. Sniping between Robert and Latimer has been deleted. While I sometimes let this go, I don’t want it to clutter up a technical, high traffic thread.

  106. Punksta | November 6, 2011 at 9:20 am |
    If AGW was correct, the last 10 years would be definitively rising.

    No, not ncessarily. It is still possible for other, natural forces be acting so as to cool, and thus offsetting AGW.

    ———————-

    Or the warming from 1975-1998 was just a normal fluctation, nothing to do with CO2 emissions. There is no way you can definitively claim the current lull is AGW masked by some other natural mechanism. Maybe this is normal, 1975-1998 was just a natural fluctation, a ripple, a change in the direction of the climate as per: https://pantherfile.uwm.edu/kswanson/www/publications/2008GL037022_all.pdf

    • There is no way you can definitively claim the current lull is AGW masked by some other natural mechanism. Maybe this is normal, 1975-1998 was just a natural fluctation, a ripple, a change in the direction of the climate
      Yes indeed.

  107. I have a proposal to all the AGW faithful who think this flat trend is temporary and that within 5 years it will take off up again to pledge a substantal amount of money to the charity of your choice should you be wrong.

    Me? No I’m not foolish enough to know what the future will do next year let alone 5 years.

  108. Schrodinger's Cat

    In the early Seventies the global cooling prompted climate scientists to claim that we were entering an ice age. During the next 30 years the planet warmed, prompting some of the same scientists to claim that we were warming due to CO2 emissions and the warming would be catastrophic (please send more funding to enable us to quantify the doom). Now we appear to be entering a new cooling phase.

    Cooling causes more deaths than warming, so,climate scientists, please get your ‘Catastrophic cooling will cause destruction of humanity’ funding requests in now to beat the rush.

    Those of you heavily committed to the current cycle, such as searching for the missing heat, can delay funding applications until the cooling phase is over and the missing heat can then be declared as ‘found’.

    • “In the early Seventies the global cooling prompted climate scientists to claim that we were entering an ice age. During the next 30 years the planet warmed, prompting some of the same scientists to claim that we were warming due to CO2 emissions and the warming would be catastrophic (please send more funding to enable us to quantify the doom).”
      This is not actually true. A small minority of predictions for future climate were in the cooling direction, these were outnumbered by predictions of no change and far more still that predicted warming.

      http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F2008BAMS2370.1

      Given that we know more about climate today than we did then, especially with the intervening decades of accumulated data, is it really any surprise that the already small number of cooling predictions has shrunk to nil? This is because science tends to improve over time and converge on the more correct answers, leaving behind those that don’t work.
      Today there are almost no predictions of cooling in the literature, though many self-styled “skeptics” have made predictions that haven’t panned out.
      Do not be ready to leap up and shout that there is a cooling phase in action, as the data show the warming continues despite short-term slumps.

      http://data.giss.nasa.gov/gistemp/graphs/

      “Cooling causes more deaths than warming, so,climate scientists, please get your ‘Catastrophic cooling will cause destruction of humanity’ funding requests in now to beat the rush.”
      We actually don’t have a solid answer on which extremes cause the most deaths, but since we’re unlikely to return even to anything like the climate of the mid-20th century it’s pretty unwise to recommend that hypothetical fund-chasers start doomsaying about an impending ice age.
      Especially since you haven’t offered any physical mechanism that would drive the climate downwards. I notice you seem to be overlooking one of the major factors that prompted concerns about which way the climate would turn back in your “early Seventies” argument, the negative climate forcing of aerosols and other particulate pollutants that drove global dimming. Are you suggesting that we’re going to experience a resurgence of dirty skies to block out the sun and drive temperatures down again? If so, I would love to see your evidence.

      • science tends to improve over time and converge on the more correct answers, leaving behind those that don’t work.

        Except when the vested interests of the science’s funder, are best served by everyone believing or hearing the incorrect or unsubstantiated answers.

      • Wheels

        There have been several studies from all over the world, which point out that cold kills more humans than heat

        T. Moore (Stanford) study: “Health Benefits of Warmer Climate”

        http://www.stanford.edu/~moore/HealthBenefitsofWarmer.html

        “Simply put, warmer weather means fewer deaths.”

        Goklany study: “Death and Death Rates Due to
        Extreme Weather Events- Global and U.S. Trends, 1900–2006”

        http://www.csccc.info/reports/report_23.pdf

        Deaths from all extreme weather events (USA and global) have decreased sharply over 20th century. Extreme cold caused roughly twice the number of deaths in the USA as extreme heat. [Note: mortality data from the Center for Disease Control (CDC)]

        The National Bureau of Economic Research (NBER) cites a study that shows the “annual deaths attributed to cold weather” in the USA averaged 27,940 per year since the mid-1980′s. This is over twenty times higher than the direct deaths from cold weather reported above. Many of these are directly related to heart attacks while shoveling snow, traffic accidents during icy and snowy weather, etc., which are not included in the above weather related death statistic.

        Goklany study: “Winter kills more than summer”

        http://heartland.org/policy-documents/winter-kills-excess-deaths-winter-months

        Falagas et al.: “Seasonality of mortality: the September phenomenon in Mediterranean countries”

        http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2761439/?itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_SingleItemSupl.Pubmed_DiscoveryDbLinks&ordinalpos=1&tool=pubmed

        There are two added studies I have read (one from London, covering several European countries, and one from a U.S. medical doctor and physicist, Howard Maccabee, covering global statistics), but I do not have links handy.

        Max

      • Max,

        Living in Australia I can understand the desire of others to live in a warmish climate.

        But, instead of cheering on AGW, (which incidentally I thought you were disputing anyway?) wouldn’t it make more sense for you Americans to migrate to somewhere like Florida, or Southern California? Or you Swiss, to head off to Spain?

        Better than messing about with something you don’t understand, wouldn’t you say?

      • tt

        A lot of northern and central Europeans are doing exactly what you suggest once they retire (moving south to Spain, etc.).

        So are a lot of Americans (retiring in Florida or Arizona).

        It’s because they cannot wait for AGW to do its magic; 0.6C per century is too slow to be of much use, and besides, it seem to have stopped warming recently (topic of this thread).

        Max.

    • Oh no. Not the “they said there was going to be an ice age in the 70′s argument”!

      http://www.skepticalscience.com/ice-age-predictions-in-1970s.htm

      • tempterrain

        See:

        John Cook may be too young to have noticed what was going on in the 1970s, but there was a “global cooling scare”, which was not only confined to the popular press, but also had the support of many climate scientists at the time, as the video documents.

        Admittedly, it was a “mini-scare” compared to the multi-billion dollar AGW business of today..

        Max

      • So…You can find a few climate scientists today who still believe that it is cooling…or not warming…and write books about it There is never totally unanimous opinion. The relevant questions are: What was being said in the scientific literature AND what did respected scientific bodies like NAS say about it? And, the answer is that the scientific literature was split, with more concern about warming than cooling and an NAS report in the mid 70s said that there were concerns about the future state of the climate but scientists were not yet able to predict in which direction the future climate would go. They correctly identified the various forces acting in the various directions (greenhouse gases => warming, aerosols => cooling, on longer time scales expect natural cooling from interglacial into an ice age); however, they said more research was needed to reliably say what path the climate would take.

        So, in fact, the past experience shows that the scientific community was cautious when they didn’t think they had enough information yet and made the right call. Thus it gives no reason to ignore science and go back to the Dark Ages as the denialist community seems to desire to do.

  109. Here is a quite recent paper by A.Mazzarella & N. Scaffetta likely to explain the pause or even the stop for the next 2 decades.

    Evidences for a quasi 60-year North Atlantic Oscillation since 1700 and its meaning for global climate change
    Published in Theoretical Applied Climatology (DOI 10.1007/s00704-011-0499-4) last august

    link

    Abstract
    The North Atlantic Oscillation (NAO) obtained using instrumental and documentary proxy predictors from Eurasia is found to be characterized by a quasi 60-year dominant oscillation since 1650. This pattern emerges clearly once the NAO record is time integrated to stress its comparison with the temperature record. The integrated NAO (INAO) is found to well correlate with the length of the day (since 1650) and the global surface sea temperature record HadSST2 and HadSST3 (since 1850). These findings suggest that INAO can be used as a good proxy for global climate change, and that a ~60-year cycle exists in the global climate since at least 1700. Finally, the INAO ~60-year oscillation well correlates with the ~60-year oscillations found in the historical European aurora record since 1700, which suggests that this ~60-year dominant climatic cycle has a solar–astronomical origin.

  110. BEST shows a year that is .3 warmer than 1998 so a plateauing of temperatures in BEST is hard to see.

  111. Here are two possible reasons why people don’t say the following PAUSE (actually a slight decline) what it really is.

    http://bit.ly/rYp5OM

    Reason One (Tolstoy):

    know that most men, including those at ease with problems of the greatest complexity, can seldom accept even the simplest and most obvious truth if it be such as would oblige them to admit the falsity of conclusions which they have delighted in explaining to colleagues, which they have proudly taught to others, and which they have woven, thread by thread, into the fabric of their lives.

    Reason Two (Elbert Hubbard):

    If you work for a man, then by all means, work for him. If he pays you wages which supply your bread and butter, speak well of him; stand by him and the institution he represents. If put to a pinch, an ounce of loyalty is worth a pound of cleverness.

    If you must vilify, condemn and eternally disparage – resign your position, and when you are outside, damn to your hearts content. But as long as you are part of the institution, do not condemn it. If you do that , you are loosening the tendrils that are holding you to the institution, and by the first high wind that comes along, you will be uprooted and blown away, and probably will never know why.

  112. To compare with GISS, the record temperature of 1998 was beaten in 2005, 2007, 2009, and 2010 by .07, .02, .01, and .07 C. BEST shows .07, .20, .04, and .30, substantially warmer. Even with GISS land only the max difference is .13.

    • MikeN

      BEST (land-only data) shows a flat trend over past 10 years.

      HadCRUT3 (land and sea data) shows a slight cooling trend over past 10 years.

      But this has been discussed ad nauseam on this thread.

      Max

  113. manacker, I am not seeing the flat trend in BEST since 1998.
    The have values of 1.2 and 1.1 compared to .9 in 1998. Many of the people who have posted about a flat trend are posting HADCRUT, which of course says nothing about a trend in BEST data.

    • MikeN

      I have written that the BEST (land only) record shows a flat trend for the past ten years

      This means since the start of 2001 NOT since 1998.

      Don’t arbitrarily move the goalposts, Mike.

      Max

  114. Manacker even that is not true. Woodfortrees shows .25 or so from 2001 to 2009. Adding in the 5 months of 2010 still has a positive trend over .15 per decade

    http://www.woodfortrees.org/plot/best/from:2001/to:2010/trend/plot/best/from:2001/to:2009/trend/plot/best/from:1975/to:2010.