What we agree(?) on

by Judith Curry

This post draws heavily from Bishop Hill’s post with (almost) the same title, related to the Cambridge Workshop discussed on the previous thread. Specifically, this addresses the attempt by Dr. Eric Wolff to find a measure of agreement between the two sides in the climate debate.  I attempted something similar on a previous Climate Etc. thread titled What we know with confidence.

Dr. Wolff’s summary points (as per Bishop Hill) are listed below:

1.  Everyone in the room agrees that CO2 does absorb infrared radiation, as observed in the lab

JC comment:  I think we can declare this one 99.99% accepted

2.  I think everyone in the room agrees that the greenhouse effect (however badly named) does occur in practice: our planet and the others with an atmosphere are warmer than they would be because of the presence of water vapour and CO2.

JC comment:  I tried valiantly to lay this one to rest with the threads on Slaying a Greenhouse Dragon, but the skydragon group isn’t buying it.  I have yet to see an interesting (let alone valid) argument from this group.  I assume they will continue to generate noise (but no light).

3.  The greenhouse effect does not saturate with increasing CO2.

JC comment:  a slightly complicated issue, but one that has been more than adequately dealt with in the published literature and the technical climate blogosphere (e.g. here).

4.  It seemed that everyone in the room agreed that the CO2 concentration in the atmosphere has risen significantly over the last 200 years

JC comment:  should be 100% agreement on this.

5.  Almost everyone in the room agrees that this is because of anthropogenic emissions (fossil fuels, cement production, forest clearance).  We did hear Ian Plimer arguing that volcanic emissions of CO2 are more important than most scientists claim.

JC comment:  the anthropogenic contribution is (should be) undisputed. However, uncertainties in the global carbon budget do leave room for arguing about the relative contribution from fossil fuels.

6. I then suggested that if we agree all these statements above, we must expect at least some warming.

JC comment: as it stands, this is an incomplete argument.

7.  I think everyone in the room agrees that the climate has warmed over the last 50 years, for whatever reason: we saw plots of land atmospheric temperature, marine atmospheric temperature, sea surface temperature, and (from Prof Svensmark) ocean heat content, all with a rising trend.

JC comment:  there should be 100% agreement on the sign of the temperature change, although there is some room to debate the actual magnitude of the increase.

8. We probably don’t agree on what has caused the warming up to now, but it seemed that Prof Lockwood and Svensmark actually agreed it was not due to solar changes, because although they disagreed on how much of the variability in the climate records is solar, they both showed solar records without a rising trend in the late 20th century.

JC comment:  the role of solar variability on 20th century warming is not settled; the IPCC AR4 gave “low confidence” to our understanding of solar variability.  There has been a spate of recent solar analyses, but the issues of direct vs indirect solar effects (e.g. Svensmark’s ideas) is far from settled.

9.  On sea level, I said that I had a problem in the context of the day, because this was the first time I had ever been in a room where someone had claimed (as Prof Morner did) that sea level has not been rising in recent decades at all.  I therefore can’t claim we agreed, only that this was a very unusual room.  However, I suggested that we can agree that, IF it warms, sea level will rise, since ice definitely melts on warming, and the density of seawater definitely drops as you warm it.

JC comment: if it warms and there are no confounding factors like coastal subsidence and isostatic causes and sedimentation in deltas, then yes sea level will rise.  However in many locations geological factors swamp eustatic sea level rise, and sea level is actually decreasing.  The scientific and socioeconomic impacts of sea level rise are fundamentally local, and emphasizing the global rather than local sea rise issues isn’t very useful IMO.

10. Finally we come to where the real uncertainties between scientists lie, about the strength of the feedbacks on warming induced by CO2, with clouds a particularly prominent issue because they have competing effects that are hard to quantify.  I suggested to the audience that we could probably agree that the likely range of warming from a doubling of CO2 was 2-4.5 degrees C (which is actually the IPCC range).  This was the first time I really got any dissent, so I then asked whether we could all agree on at least 1 degree (implying no positive feedbacks at all, even from increased water vapour and sea ice loss).  I got one dissenting voice for that, but there wasn’t a chance to find which of the preceding statements he had disagreed with (it would be necessary to disagree somewhere up the line to be consistent with dissenting on this one).

JC comment: indeed, this is where the biggest uncertainties lie.  I don’t buy the IPCC’s likely/very likely ranges for climate sensitivity (see this previous post).  Re the 1 degree no feedback response, see this previous thread.

Summary

This was certainly an interesting exercise by Wolff, see also the Bishop Hill thread for Montford’s comments.  The bottom line is that there are a few basics that everyone agrees upon, and plenty  of topics where there is legitimate disagreement (which signals significant ignorance about the topic).

355 responses to “What we agree(?) on

  1. Of the 68 comments currently on the Bishop Hill post I see significant disagreement with some or all of those positions.

    Other than the fact that you agree with what was said what’s your basis for statements such as

    “The bottom line is that there are a few basics that everyone agrees upon, and plenty of topics where there is legitimate disagreement (which signals significant ignorance about the topic).”

    You are arbitrarily defining “legitimate agreement”. It’s highly disingenuous to claim practitioners of a particular discipline are wrong or worse engaging in fraud and then start talking about “legitimate disagreement”.

    Do you actually read skeptical blogs? Do you read the comments posted there? Do you read the blog of “Steve Goddard” whom you attended the Lisbon conference with? Do you read Anthony Watts’ blog?

    You’ll regularly find lots of disagreement with what you claim “everyone agrees on” there.

    If you think you can open the door wide enough to push out all the people you think bad as a result of Climategate, regardless of the quality of their work or the robustness of their conclusions while still keeping out the “C02 cools the atmosphere!” people then you simply can’t.

    There’s a reason scientists generally don’t declare each other frauds or liars (in public at least) because they disagree with them. There’s a reason they don’t use terminology like high priests and dogma.

    That reason is once you put your discipline in the trash it sits there with the other trash. You can’t dust it off and declare the bits you like are still good.

    You can’t expect anyone to believe you need to spend years learning about something to understand it while also invoking simplistic arguments to tear down everything else.

    • Try posting something symmetrical to this at RC or Romm’s place.
      Something about how fear mongers are making crazy unfounded claims in the name of science and how the RC guys or Romm have no credibility if they do not toss out the misanthropes and death culters.

    • If I had not known this blog, using your criteria your comment would make me shun it.

      • shaperoo seems to think that it is OK for Hansen, Mann, Schmidt, Brifa, Jones, etc. etc. etc. to dump their discipline in the trash, if it is for a good cause.
        Also, his assertion that someone’s work stands apart from their ethics is interesting and unfounded.

    • John from CA

      “The bottom line is that there are a few basics that everyone agrees upon, and plenty of topics where there is legitimate disagreement (which signals significant ignorance about the topic).”

      I think what Dr. Curry is saying, Climate Science can’t hide behind the “its to complicated to explain” premise and needs to openly embrace the its short comings.

      This isn’t hard to quantify. One only needs to look at the current Climate Science proposals for funding to discover the need to properly research the Carbon Cycle, Water Cycle, etc.

      The one thing we can all agree on, it simply doesn’t make sense to waste trillions on an unproven tipping point theory when we could actually achieve more by simply addressing real problems.

  2. Starting at the beginning, regarding point #1: a general philosphical point, what happens in Las Vegas stays in Las Vegas and what happens in the lab STAYS in the lab. Translating the narrow and specific of the wet lab to the large and generalized global atmosphere has always been susceptable to what have been the assumptions to get results in the lab. Assumption: CO2 is uniformally distributed in the atmosphere. Well, we’ll wait on that one since the CO2 sensing satillite is in the drink. Assumption: the behavior of CO2 and assumed feedbacks at the poles is the same as at the tropics: water vapor, no water vapor; possibly, but with global warming a peculiar feature of the Arctic, IMO, maybe, and then, maybe not. So my question: does the radiative transfer model work equally well all over the world, in high and low water vapor regions? altitudes? or mostly?, or it depends?…. I certainly don’t know; does anybody? and the…proof? Is CO2 the regulator of the “Greenhouse Effect”? the fine tuning thermostat? You’ll have evidence for that, I just missed it.

    • See this previous thread on confidence in radiative transfer models

      http://judithcurry.com/2010/12/05/confidence-in-radiative-transfer-models/

      • Dear Dr. Curry:

        Gases, including air absorbs solar radiation and this is an disputed fact supported by experiments. However, there is no such a thing as heat trapping gases, never existed anywhere. Had heat trapping gases existed, there would have been already a useful practical application for them that could help in solving the energy-environment issue, a profitable business. But we do not have a single practical application or observation that supports the existence of the greenhouse gas effect; on the contrary, we have experiments that prove otherwise, and heat trapping gasses are simply fiction and their related science is fiction as a result.

      • Nabil,
        You are simply wrong.
        Air is used as an insulator, and is one of the best insulators.
        Down blankets work by trapping air, as one example.

      • Funny answer from Hunter. Vaccum being an even better insulator than air, let’s conclude about a “greenhouse vaccum effect“…

      • David L. Hagen

        Judith Re:
        “3. The greenhouse effect does not saturate with increasing CO2.”

        This depends on the interpretation of “saturate” vs “greenhouse effect.”.
        CO2 absorption alone is more logrithmic with intensity and thus technically does not “saturate”..

        However, for the confounding details of actual reality, see Ferenc Miskolczi’s latest results:
        The stable stationary value of the Earth’s global average atmospheric infrared optical thickness
        Presented by Miklos Zagoni, EGU2011 Vienna

        From quantitative Line By Line evaluations of the global optical depth using the best available dat from 1948-2008, Miskolczi finds:

        The dynamics of the greenhouse effect depend on the dynamics of the absorbed solar radiation and the space-time distribution of the atmospheric humidity. The global distribution of the IR optical thickness is fundamentally stochastic. The instantaneous effective values are governed by the turbulent mixing of H2O in the air and the global (meridional ) redistribution of the thermal energy resulted from the general (atmospheric and oceanic) circulation. . . .

        Global mean IR absorption does not follow the CO2 increase (from 1948 to 2008). Greenhouse effect and the 21.6% increase of CO2 in the last 61 years are unrelated. Atmospheric H2O does but CO2 does not correlate with the IR optical depth. . . .Atmospheric CO2 increase can not be the reason of global warming. . . .IR Optical Depth has no correlation with time. The strong CO2 signal in any time series is not present in the IR optical depth data.

        Thus Miskolczi finds there is NO correlation of global optical depth with CO2, only with H2O.
        Furthermore, the global average is about constant – with very little trend.
        So would “stationary” or “static” be better words than “saturated”?

        Some will argue that teh TIGR2 data is flawed. What better is there?
        Miskolczi has also adjusted to match satellite data.

        Has anyone else taken the effort to actually quantitatively evaluate the global optical depth and how it changes – or explain why it does not?

  3. There is another dimension to this discussion. Not all of us are competent to have opinions in all areas. Some of us are very competent to evaluate and comment on specific areas; in some cases more so that someone with a more general climate science background. By this I mean areas such as instrumentation, statistics, economics, civil engineering, solar physics, etc. Claiming agreement on a subject may be overstating the situation. Many areas of agreement are actually what is best described as provisional, based upon trust that the research behind the claim is correctly performed. Likewise, disagreement may be from misunderstanding of the underlying science. Or, disagreement may be from specific errors detected by people experienced and fully qualified in those subjects. Simply having folks raise their hands to show agreement or disagreement is probably providing a poor representation of real views.

    • Yes. And those of us that know systems know that individually you can know every part and function but when it’s put together you can easily have something that doesn’t work. The are principles of design that can often not be seen.

      Sometimes the sum is greater than the parts or you can have incommensurate scaling or something else emerges.

      So such lists will be deceptive if you put too much into them without recognizing the complexity of the system.

  4. Gary, very good points, but IMO the evidence for the points where I presume close to 100% agreement is very strong and fundamental. That leaves plenty of room for legitimate and important disagreement on the other topics.

  5. Dr. Curry: There is indeed a lot more disagreement than your summary suggests. Note too that in several cases you say there is agreement but not on magnitudes. These are among the greatest disagreements! Plus several key steps are not listed.

    • I agree that there is substantial disagreement on magnitudes, and this list is far from complete

      • In several points you indicated that there is agreement on the sign, but uncertainty on the magnitude. That may be implied to mean that there is an agreement on a relatively narrow range of possible values as the alternative might lead to some uncertainty also on the sign. My own view is that all such cases on the list indeed fit the description that almost everybody knowledgeable on the issue considered could agree also on the most important quantity (or dominant component) within reasonable limits, which might allow 30% deviation in some case and 10% in another, but always significantly less than 50%.

        I have been involved here in an argument on one such point: the share of the anthropogenic emissions in the increase of CO2 concentration since start of Mauna Loa observations. It’s clear that there are uncertainties in the knowledge and there is also disagreement on, how the anthropogenic contribution should be defined. The uncertainties in knowledge are perhaps a few percent of the whole increase and the different reasonable definitions may differ even more from each other, but my view is that the whole uncertainty cannot be more than 20% and even that is a high estimate.

        Similarly it’s not enough to say that there is an agreement on the sign of the increase in temperature over 50 years, but the agreement should be extended to some quantitative limits to be meaningful.

        Stating only that we agree or should agree on the sign, but not on the magnitude leaves too much open for those, whose quantitative estimate is far from almost everybody else.

      • Pekka

        I believe the disagreement is BOTH on the magnitude and the sign of the net climate feedback.

        We are talking about a postulated no-feedback 2xCO2 sensitivity of around 1C (IPCC, Myhre et al.).

        Spencer/Lindzen talk about a CS with all feedbacks of around 0.6C, while IPCC talks about 2.0 to 4.5C.

        That is the quantitative range of the basic disagreement between scientists on CS.

        Max

      • Max,
        I didn’t refer to all points, I was commenting only on those points, where Judith indicated that there is a general agreement on the sign.

        We have already seen in this thread that there are hardly any statement agreed on by everybody, but there are clearly statements agreed on by a large majority of both main stream scientists and knowledgeable skeptics. The sign of the feedback might be marginally on either side on this criterion. Wolff reported that all but one agreed in that room. That might well represent fairly the ratio also in a wider knowledgeable group of scientists and skeptics.

        (I have used the expression “knowledgeable skeptic” to describe skeptics, who have spent significant effort to learn about climate change without further intended implication about their opinions.)

    • David L. Hagen

      IPCC AR4 declared even the sign uncertain:
      “[T]he sign [positive or negative] of the climate change radiative feedback associated with the combined effects of dynamical and temperature changes on extratropical clouds is still unknown.” IPCC AR4, WG1, p 637

      Spencer similarly notes high uncertainty in cloud feedback as well as in cause/effect on clouds. “Five Reasons Why Water Vapor Feedback Might Not Be Positive”

      What progress has there been and what is needed to quantify these radiative feedbacks to both get confidence in the sign and the magnitude of the feedbacks?

  6. The bottom line is that there are a few basics that everyone agrees upon

    I only agree to a global warming rate of only about 0.06 deg per decade
    For 1940 to 2000=>http://bit.ly/mCgC8Q

    Or

    For 1880 to 2000=>http://bit.ly/jbhKZ1

    Not to the following 0.16 deg per decade warming.

    For 1970 to 2000=>http://bit.ly/jG3ch3

    This is because this period takes into account only a single warming phase.

    Do we agree on this basic?

    • You forgot to account for the fact that the extra added CO2 in the atmosphere is four times larger in 2000 than in 1940, so the rate should be far from linear, and later years give a far better idea of the future change.

      • If later year give a better idea of future change, look at the past decade. No significant warming and lots of snow that will promote lots of cooling.

      • The 2000’s were indeed 0.15 degrees warmer than the 1990’s, which proves the point.

      • Do you actually wish to assert that
        a) 0.15 degrees is a number with any significant meaning on a global basis
        and
        b) that 0.15 degrees is a number that has any precision ?

      • It has more precision than taking a few years from 2000 to 2010 and saying warming is not occurring. Complain about those people.

      • Jim D,
        Both are equally credible, and equally meaningless.
        But your seizing on to the former is your excuse to do expensive wasteful polices.
        The second allows us to progress and look at reasonable policies.

      • andrew adams

        hunter,

        It would be silly to make any policy decisions based on what has happened in just 10 years.

      • aa –
        It would be silly to make any policy decisions based on what has happened in just 10 years.

        But it was perfectly acceptable to make policy decisions on the 10 years that Hansen had when he testified in 1988?

        There’s a word for that attitude. Hypocrisy, I believe?

      • aa,
        For climate issues, besides the question of how mitigation can possibly be considered as a policy tool, is the question of time scale.
        Using the time from the late 1970’s to the late 1980’s as the basis for making claims about global catastrophe was flat out bogus and irrresponsible.
        Pretending that 0.x degrees of alleged change in a system that is very difficult to measure meaningfully, and has a daily swings in temperature of 10’s of degrees, is ludicrous.

      • Is your number subject to starting point cherry picking or the climate (or weather ) cares for decade beginning or ending?

      • The thing about choosing only decade-averaged temperatures is that it gives robust changes from one decade to the next, regardless of starting point for any decades since the late 70’s. It is always from 0.1 C to 0.2 C per decade.

      • Four times larger is a huge Exaggeration

      • OK, maybe 3.5. About 305 ppm in 1940, 370 in 2000, compared to 280 baseline, so it goes from 25 to 90 added CO2.

      • CO2 is a trace gas. a fraction of a trace is a fraction of a trace. I am sure that it has a fraction of a trace influence on global warming.

      • Water vapor is only a trace gas too (less than 0.5%), but look at all the rain and snow and clouds it causes. This is a common misconception that people have. In the upper part of the atmosphere CO2 exceeds water vapor.

      • Jim D,
        You are vastly wrong on your assertion of water vapor content of the atmosphere:

        http://en.wikipedia.org/wiki/Water_vapor

        Additionally, water has the ability to triple point the atmosphere, which is significant and seems to be over looked, oddly enough.

      • The point is, yes, it is pretty effective for a trace gas too, so why does that mean CO2 should not be effective when it exceeds water vapor in large volumes of the atmosphere?

    • Dear Girma:

      I agree with you, and 0.05 to 0.07 degrees centigrade/decade is what math suggests. Please see the work posted on my website http://www.global-heat.net. Please start with Article-12 then book PDF.

    • Girma

      The “rate of past warming” was not a point of agreement (as Dr. Wolff observed). He proposed:

      I think everyone in the room agrees that the climate has warmed over the last 50 years, for whatever reason

      to which he wrote he got general agreement

      Why he picked out “the last 50 years” instead of the entire 161-year HadCRUT record is unclear to me, especially since there was just as much warming from around 1910 to 1940 as there was from 1970 to 2000 (as Phil Jones has confirmed and you have shown graphically).

      Max

  7. Mike Keller

    I believe “we agree to disagree” is a more apt description of the current state of affairs, with Hill’s attempts at creating a consensus more or less a “rope-a-dope” effort.

  8. “But it’s all right now, I’ve learned my lesson well
    You see, you can’t please everyone, so you’ve got to please yourself”
    (Rick Nelson -“Garden Party”, 1972)

    • Excellent taste!

    • That is a good old Ricky Nelson song!

      And it’s a fine position for everyone in this debate. Unfortunately, those on the climate change are singing: “You see, you can’t please everyone, but they darn well better please us.”

      • Good point.
        At least the UFO believers are not seriously demanding vast sums of public money to satisfy their obsession.
        Even rapture believers are not begging for government money or demanding huge policy changes at great cost.
        They simply want to get beamed up.
        AGW beleivers, on the other hand, demand we agree, demand a lot of money, and want to tell all of us what to do.

  9. The problem I see with lists like this, viewed a certain way, is that some fear them as “kook tests”.

    That is, for example, some might worry that there’s an attempt, simply by framing a continuum of understanding, consensus, agreement, confidence or what have you, that at some point — for example between #4 and #5 in the list above, a “kook line” will be drawn, implying that anyone who questions 1-4 can safely be dismissed by ‘reasonable people’ as a crackpot, while the fringe at 5-7 are merely suspected loons, while the 8-9’s are merely heretics who might have something rational to say, with the foregone conclusion that they’ll be talked out of their ignorant ways eventually.

    Oh. Wait, there’s some faulty assumptions underlying what I’ve just said.. But no matter.

    Indeed, though points 1-7 are very nearly insurmountably supported by evidence and argument, and 8-9 are fairly comfortable reasonable conclusions (vague as they are), from where I stand, I try not to draw such inferences myself as I suggest some may fear.

    I think we can get something productive out of attempting to draw up lists of what people engaged in a debate agree with, and not need to bash, disenfranchise or otherwise create a bias against those who disagree.

    There is no kook line here.

    • There is always a kook line. It’s necessary. Do you want to spend your time debating with people who think the earth is 6,000 years old, or that the Rapture is coming on October 21st, or that evolution is a fraud?

      Finding a kook line is the whole benefit of the exercise, although it might be more diplomatic to state the problem from the other end: In an ocean of kooks, where is the “Semmelweis line” that defines people who are far from the consensus and yet warrant respectful attention?

      • Well said. I’m trying to identify where the more substantive issues lie.

      • Sadly, Semmelweis was considered until after his death on the very far end of the kook continuum by far, far too many, and given little respect.

        It’s good and proper to identify substantive issues in the main for the major elements of the debate if one seeks productive and efficient resolution. That’s debating.

        It’s important and — though counterintuitive — reasonable to leave open room for scientific investigation to consider and explore independently of the wider debates even irrational-seeming claims.

        I mean, washing one’s hands to decrease infant mortality. Preposterous notion. Sounds like some sort of voodoo, really. No logic to it at all.

      • Robert

        Regarding “kook lines”:

        Do you want to spend your time debating with people who think the earth is 6,000 years old, or that the Rapture is coming on October 21st, or that evolution is a fraud?

        How about people who think we might be inundated by 6 meter waves 100 years (or even 10 years) from now as a result of human CO2 emissions, or that 450 ppmv CO2 (no, wait a minute, 350 ppmv) is a “dangerous” level leading to “irreversible” “tipping points” resulting in “deleterious changes” in our climate and “extinction of species”?

        Kooks are kooks, no matter what other category they may fall into.

        Max

  10. Agreement on 4 is far from 100 percent for 200 years. The core debate is ice core data versus Beck data, but it is much more complex than that.

    • Beck’s analysis seems quite kooky, do you have anything else that illuminates this issue from the skeptical perspective?

      • Statement written for the Hearing before the US Senate Committee on Commerce, Science, and Transportation
        Climate Change: Incorrect information on pre-industrial CO2

        March 19, 2004

        Statement of Prof. Zbigniew Jaworowski
        Chairman, Scientific Council of Central Laboratory for Radiological Protection
        Warsaw, Poland

        Prof. Jaworowski statement claims ice CO2 readings are off.

      • I did not refer to Beck’s analysis, but to his data, something like 95,000 measurements. There is also stomata data, etc. Then there are the various problems with the ice core gas extraction data, a research topic all its own. This is a large issue with a lot of participants. Moreover, with all due respect what you personally find “not interesting” or “kooky” is not the issue. We are talking about the demographics of belief, which is itself a scientific question.

      • Thanks for the details, I’m trying to understand the demographics of belief on this one, since I rarely hear these issues mentioned.

      • David – there are issues with both the Beck data and, particularly with his attempt at creating a time series from it. Relative to the data, nearly all, if not all, of the measurements are taken from near surface locations which are not necessarily representative of background tropospheric conditions. It is well known that near surface CO2 concentrations can vary widely even diurnally based on plants’ respiration cycle. Further many were taken in urban areas where there were numerous combustion sources which would lead to higher near surface CO2 concentrations and again not representative of tropospheric background. So even if we take the every one of the CO2 readings in Beck’s compilation as accurate, they are likely not representative of the true tropospheric background concentrations.
        Relative to their accuracy, early wet analytical methods had a precision of about +/- 100 ppm with a detection limit of right around 250 to 300 ppm, with many opportunities for a slight bias high if proper drying of the sample, etc. were not followed to a T. So while many of the readings may be reasonably accurate, without doing a through QA/QC of all procedures followed for each one, it would be safe to assume that at least some of them aren’t 100% accurate.

        Finally, the killer for me relative to Beck’s analysis is that you cannot create a valid time series ofaverage atmospheric CO2 concentrations by taking measurements from one location at one time, then measurments from another location at another, measurementts from a third location at another time, etc. To be a valid time series, you either have to have ongoing measurements from the same location or ongoing measurements from the same set of locations. Comparing 1910 CO2 measurements in, let’s say India, to measurements collected in Germany during WWII and calling it a time series is not valid.

      • I think the basic lay-skeptic idea with ice cores problems is that over time co2 will drift due to brownian motion and gravity and because ice is somewhat plastic and there are ice streams and compression changes that change ice properties over time. That’s my elementary school science explanation anyhow. One would hope that the people doing the ice cores would be able to calibrate their results with real world measurements and other methods, including statistical verification but apparently there are recent studies that dispute the accuracy of ice cores but it would not be totally surprising if problems with ice core measurements were found.

  11. 5 is certainly controversial. For example, Hayden and others argue that the co2 increase is entirely due to ocean warming.

    • Out of interest, how do they explain that the ocean is acidifying at the same time?

      • How do you claim that which is not happening?

      • So you honestly think CO2 in the ocean is decreasing or staying constant. Is there a reference for that, or did you just make it up? Haynie seems to have avoided this issue because it doesn’t fit his theory.

      • Jim D: Do we have good knowledge of the activity of all CO2 sources within the ocean? Exchange with the atmosphere is not to only factor in play.

      • You mean that undersea volcanoes have suddenly become active in the industrial age?

      • Jim, show me data that confirms no change in volcanic activity along 30,000 km of mid-ocean rift since the industrial revolution. 40 years ago we did not even know about a separate ecosystem down there.

        How many times more CO2 is held within the oceans than is in the atmosphere? Consider the biomass within the oceans and limestone as a buffering agent.

        You seem to be asserting that CO2 exchange with the ocean is minimal. We do not agree that our knowledge is strong enough to assert that

      • You seem to think that fossil fuel CO2 added to the atmosphere cannot account for the increase when it is more than double the increase, and the rest goes mainly to the ocean. Why would you even need another explanation if you have closed the budget already? If you have your undersea volcanoes, you are going to need an explanation of what absorbs the fossil CO2, but leaves the volcano CO2 alone, otherwise the problem is worse than we thought with the CO2.

      • No, I think that the CO2 cycle in the oceans are not well understood. It seems that the facts show that the oceans are not ‘acidifying’.
        But it is fun for believers to talk of ‘acidification’ in a massively basic system, sort of like telling spooky stories around the campfire at summer camp.

      • Are you making the argument that it can’t be acidifying because the oceans are basic?
        Would you allow the argument that the oceans are becoming less basic?

        The warmist argument is that the oceans cannot be the source of the increase in atmospheric CO2 because the concentration of CO2 in the oceans is increasing. (as H2CO3, HCO3-, and CO32-)

        Also, acidifying means a lowering of pH, whatever the intial pH is.

        Also, the qualities of acidity and basicity are directly correlated, if you know one, you know the other in aqueous environments.

      • There seems to be an edit war on “Ocean Acidification” in Wikipedea. 50 edits in 5 weeks.

        http://en.wikipedia.org/w/index.php?title=Ocean_acidification&action=history

        The ph of the ocean is reported to have moved from 8.
        8.25 to 8.14,[2] representing an increase of approaching 30% in “acidity” (H+ ion concentration)
        … in the last 240 years. Seeing as how an EQUAL increase of H+ results in a ph of 8.05, it’s not going to keep me up nights.
        pH [H+]
        8.25 5.62E-09
        8.14 7.24E-09
        8.05 8.87E-09

        It reminds me of a favorite saying from “The Trouble with Tribbles”: “Twice nothing is still nothing.”

      • Stephen Rasey

        Watch out for “OA” (the new “buzzword”).

        Once the thermometers of the world no longer play along with the premise that AGW is a real and present danger, we’ve always got “OA” to fall back on.

        Scientists have measured an “alarming increase of acidity” from 5.62 to 8.87!

        No one will worry about the fact that we are talking about parts per trillion, unless someone explains that one part per trillion of the distance to the sun is 15 cm (or 6 inches).

        “Much ado about nothing” (as you write).

        Max

      • I am not defending these positions, merely pointing them out. The question on the table is what is, and is not controversial, not who is right. It is a scientific question regarding the demographics of belief. This requires understanding the issues, in their full scope and complexity, which few do. My field is issue analysis and I have been studying these issues for 19 years. I think I understand their logical structure as well as anyone, if not better. See my little textbook: http://www.stemed.info/reports/Wojick_Issue_Analysis_txt.pdf

      • “My field is issue analysis”

        That’s the quote of the day. Where a philosophy degree will take you, eh?

        Given your history as a nonscientist paid by the Heritage foundation and the Cato Institute to pontificate about science, I think a more accurate description of your mandate would be “issue obfuscation.”

      • Alas, I never worked for the fancy folks at Cato or Heritage, but I did get funding for climate change issue analyses from Greening Earth (rural electric co-ops) and API (big oil). I am a cognitive scientist, specializing in the applied logic of complex issues, something most people know nothing about. When I address climate scientists I usually say “you study climate while I study you, more specifically your reasoning.” My Ph.D. is in the Logic (or Philosophy) of Science so I understand certain aspects of science (the logic) far better than the bench scientists do. As it happens, clarity favors skepticism.

      • “I am a cognitive scientist, specializing in the applied logic of complex issues, something most people know nothing about.”

        That’s because it’s not a real thing. Anyone can call themselves a “cognitive scientist,” but unless your degree is in psychology, sociology, psychiatry, or neuroanatomy, you are no more a “scientist” than a “sanitation engineer” is an engineer.

        You have a degree in philosophy. You could call yourself a “cognitive philosopher” if you wanted, but calling yourself a “scientist” is just dishonest.

      • If you look up “cognitive science” you will find philosophers included, especially those of us trained in technical topics like mathematical logic and concept analysis. http://en.wikipedia.org/wiki/Cognitive_science

        For example, I have a diagnostic system of 126 kinds of confusion, based on a lot of empirical research. I do mathematical modeling of the diffusion of scientific issues, also based on empirical data. I have just developed an algorithm to find and map the core literature on a given scientific issue. This work is called scientometrics. http://en.wikipedia.org/wiki/Scientometrics

        Mathematical description of the real world is science, and that is what I do a lot of the time. The issue tree itself is a scientific discovery, of the hidden structure of expressed thought. My kind of issue analysis is in fact an empirical science, because the structures are already there to be studied, whenever we talk or write. If I say that the climate debate has a certain structure that is a scientific claim.

        More generally, if you look at the history of philosophy a lot of what philosophers do is to articulate concepts to the point where science can take them over. The scientific concepts of momentum, inertia and kinetic energy grew out of Medievel philosophical debates about the “quantity of motion.” This is just what I have done with the concept of an “issue.”

      • Robert:

        “Given your history as a nonscientist paid by the Heritage foundation and the Cato Institute…..”

        Do you have any evidence to support this assertion?

      • Thought not…your silence speaks volumes.

      • Sure do. See his client list: http://www.bydesign.com/powervision/clients.html

        His claim here: “I never worked for the fancy folks at Cato or Heritage,”

        And on the client list: “CATO Institute.”

        Shocking that he would lie like that, eh?

        There’s more, but let’s see if you can admit one fact before we bombard you with a peck of them: David Wojick worked for the CATO Institute, and just now lied about it.

      • Thanks for your reply, Robert. In my view it is always best to back up controversial assertions. Your evidence certainly looks compelling but I would prefer to hear what David has to say about it.

  12. 6 is false because it skips over all other features of the climate system, such as feedbacks. It would only be true if it included a caveat that all else is equal, nothing else happens, or some such. Applied to climate it is a serious fallacy.

  13. Anyone want to agree that the city of Chicago spending precious resources readying itself for their imminent transformation to Baton Rouge, would be funny were it not so sad? Many generations hence, anthropologists will shake their heads in wonder at the continued foolishness of primitive man.

    • As far as I can tell, Chicago is mainly trying to manage its storm water, a long standing issue there (and also in Atlanta).

  14. 7 is a personal favorite. Both the magnitude and timing of the warming are highly controversial, and central to the debate. This is a major area of uncertainty. Agreement on the sign alone is insignificant.

    • David L. Hagen

      The relative temperature changes during the Medieval Warm Period (WMP) and Little Ice Age should be even more important in determining the cause of the late 20th century warming and relative magnitudes of anthropogenic vs natural climate changes.

  15. “Our planet and the others with an atmosphere are warmer than they would be because of the presence of water vapour and CO2.”

    Thinking about how quickly deserts cool off at night compared to more humid places … I’ll agree that water vapor makes a difference, but not CO2.

    • Bruce

      Mind explaining, “I’ll agree that water vapor makes a difference, but not CO2.” in a bit more detail?

      I mean, CO2 is special stuff and all, but why ought it break the laws of Thermodynamics when even H2O vapor obeys them?

      • There is so little CO2 it makes no real difference. There is so much H2O in the atmosphere – 8000 times as much on average from what I can find — that even a minor up and down change in humidity would completely overwhelm any chance of noticing any effects Co2 has.

      • Bruce

        Aha.

        So, you’re agreed in principle with the +AGW side, you’re just negotiating over the estimates?

        That greatly simplifies the matter; all one would need do is calculate the additional darkening due water vapor of the sky over a forest compared to a desert correlated expected temperature rise, work out the logarithms, compare absorbtivity CO2 vs. H2O, and then you’d know if the ratio were indeed on the scale of under 1/8000th, or something more significant?

        Sounds straightforward enough.

      • Its just too bad that during the Eemian (for example) Co2 ppm always lagged behind temperature as if more Co2 in the atmosphere was related to temperature, not the other way around.

        (PS the 8000 number is wrong. My bad (googling) )

      • Bruce

        You don’t have to go back to the Eemian, or back at all.

        CO2 ppm rises measurably follow temperature rises today regionally.

        Though the word ‘always’ is different from the word ‘only’.

        A positive feedback mechanism doesn’t preclude all other mechanisms. Indeed, it rather suggests other seed mechanisms.

        And no worries about the google-fu.

        My own estimate by eyeballing the absorbtion spectrum graphs is that for equal optical densities of CO2 and H2O, CO2 contributes perhaps a quarter as much absorbtivity as H2O vapor.

        Since both CO2 and H2O are nonsaturating for most of their absorbtion spectra, and significantly non-overlapping, and there is a logarithmic relationship of some degree involved as concentrations increase, we expect the lesser concentration gas (CO2) to gain more impact per additional optical density than the (far higher) concentration H2O vapor, but would need some clever mathematically-oriented investigator to calculate the ratios given CO2’s somewhat narrower absorbtion bands, bounded on “at least 25% for equal added optical density of CO2″.

        Also, as we’re speaking of optical density, not concentration, we’re dealing with ratios that rise as a square (area), not cube (volume), which again favors increasing impact per unit increase of the lower concentration gas (CO2).

        Since we’re trying to estimate sensitivity CO2 from sensitivity H2O by comparing forests and deserts and then working from basic optical properties, we’ll have to be careful to state that we’re not discussing actual CO2 +AGW impacts, merely a ballpark estimate to determine whether CO2 might be significant, on the principle Bruce enunciated.

        So, how much temperature difference do equivalent forests see over deserts, and what is the ratio of H2O vapor change on the logarithmic optical density curve compared to CO2’s measured increase from 280 ppmv to 390 ppmv?

        If the forest/desert temperature difference were so much as 10C, and the H2O:CO2 ratio based on (390 ppmv – 280 ppmv) 110 ppmv CO2 at the point on the logarithmic CO2 curve as little as the equivalent of 265 ppmv effective (depending on square of the cube root of the slope of the logarithm of H2O), then we’d predict CO2 had on the order of a 1C rise largely due human emissions from the dawn of the industrial revolution.

        If only I were any good at math.

  16. Nobody mentions sunshine. Not the IPCC either.

    Bright Sunshine Hours are up over the 20th century in enough places and it goes up and down like the temperature record. But this is mostly ignored or people try and change the topic to TSI.

    • This touches on another factor that “shall not be named.” Our civilization has been working quite hard at cleaning up combustion exhaust. Could it be that a significant part of any real warming comes from the stuff we have taken OUT of the air the last 30 years? Now China’s exhaust products are rising sharply at the same time temperatures are stable to declining. Could be coincidence. Could be related. There will not be agreement.

      • Thats a good theory. The air used to be amazingly filthy.

      • This is an often cited topic the team’s scientific papers. Why are you saying it “shall not be named”?

      • TSI gets mention. I searched the IPCC website. Sunshine is not mentioned.

      • I say “shall not be named” because I do not recall anyone in the press mentioning that Global Warming might in part be a side efect of the Clean Air Act.

        I have not seen it here either. For instance, can we add an agreement that some part of #7 is a result of EPA regs. (I didn’t think so.)

  17. wayne arnold

    Re: point 6
    The warming of the last 50 years needs to be compared to previous warming
    Using the GISS basic Global Land -Ocean Temperature Index Graph, you can see that if the 1940s and 1960 were hotter within the green uncertainty bars and the 1890s were colder, then the warming between 1890 & 1940 would would be more than the present warming.

  18. wayne arnold

    Re: point 6 OOPS!! I meant point 7
    The warming of the last 50 years needs to be compared to previous warming
    Using the GISS basic Global Land -Ocean Temperature Index Graph, you can see that if the 1940s and 1960 were hotter within the green uncertainty bars and the 1890s were colder, then the warming between 1890 & 1940 would would be more than the present warming.

    • I find it interesting that sunspot numbers approximately doubled in the first half of the 20th century. I would not rule out some kind of a solar effect.

      • Jim D

        I’ve long suspected something along the same lines myself. Sunspot numbers double.. and the human population doubles.

        Coincidence? I think not!

        Clearly, sunspots cause fertility to rise.

      • Yes, crazy idea that the sun might have something to do with temperatures. What was I thinking?

      • What a great example of your analytical skills, Bart R.

      • Bart R

        It’s even better than that.

        – Atmospheric CO2 has risen.

        – At the same time, human life expectancy has risen almost on lock-step.

        Higher CO2 levels are apparently good for humans.

        Max

      • Ah, but CO2 rise is global, and human life expectancy growth is regional.

        Indeed, the disparity in human lifespan regionally is what has grown as CO2 has risen.

        Likewise, and through no coincidence, relative incomes have had a similar rise in their discrepancy worldwide, too.

        Higher CO2 levels tend by your logic to cause social inequity, which historians (who are never wrong, historically) argue leads to violence.

      • Bart R

        Human life expectancy is local, as are human emissions of CO2 (supposedly the primary contributor to increased atmospheric CO2 levels).

        Local regions with higher CO2 emissions also enjoy higher life expectancy.

        Max

      • and higher CO2 leads to higher incomes, if I understand Bart R correctly.

      • Teddy

        Only if you understand me ironically.

        Higher CO2 exploitation can lead to higher incomes for free riders, most certainly, as things currently stand.

        Were we all to be paid for our common share of CO2 budget, that too could lead to higher net incomes for the 70% of us who aren’t using more than our share of the COE2 budget.

      • Bart R,

        So who decides everyones share of the CO2 budget? Al Gore, James Cameron and Hollywood, you?

        Carbon taxes are regressive.

      • manacker

        Let’s compare:

        http://en.wikipedia.org/wiki/List_of_countries_by_life_expectancy

        http://en.wikipedia.org/wiki/List_of_countries_by_carbon_dioxide_emissions

        Huh. Correlation seems pretty weak there to me.

        Maybe you mean per capita?

        http://en.wikipedia.org/wiki/List_of_countries_by_carbon_dioxide_emissions_per_capita

        Nope, still pretty poor correlation.

        What do you mean?

      • weird, when people want to argue for a solar effect they suddenly accept the temperature record.

      • steven,
        My take is that since the solar record can well explain the minor fluctuations we see, it is difficult to attribute it all to CO2.
        IOW both are equally credible, and the changes are very trivial.

      • Weird .. when it comes to climate variables warmers worship only one – Co2. Some of us actually notice the data says sunshine hours are up in the 20th century. You aren’t aren’t interested.

        Mosher Math = you can write an equation any way you like as long you only use one variable = x.

      • It’s not black and white – accept/not accept.

        Some trends for example may be accepted, but not the accuracy claimed.

        Divergent thinking you know.

  19. I find it interesting that after all these years, most of it society being bombarded with “consensus” science informing the world from on high that “the science is settled”, the scientific community is attempting to determine what they agree on. And not on some nuances around the edges, but the very basics of the hypothesis. Does this not speak volumes about the state of the science underpinning this hypothesis?

    Putting that aside, as has been properly pointed out #10 is the key. Without an answer to #10 then there really is no theory, only conjecture. It is called the enhanced greenhouse effect for a reason. About the only thing that everyone seems to agree on is that the level of that “enhancement” is the greatest source of uncertainty and disagreement. How can you have a theory when the the key component to that theory is so totally unknown? But it’s worse than that.

    Not only is the single most important factor in the theory so much in dispute and unknown, the promoters of the theory treat this great unknown were gospel. They act as if the unknown is reality, the same as they treat hypothetical climate models as real. They have polluted society and science by clouding the distinction between the known and the unknown while promoting the unknown as being reality. This is why they will be branded by history as charlatans pretending to be scientist. Selling something that they know that they do not know-fraud.

    The sooner that the real scientist out there call all this out, the sooner science can repair its place in society. People are waking up.

  20. trunkmonkey

    “Clearly, sunspots cause fertility to rise.”

    I hope you don’t mean directly.

    A new plow was invented, bumper crops filled the pantries, it was warm, everyone was ebullient. More babies were concieved, and more survived.

    I believe there should be substantial agreement on all of the points. The disagreement hinges on the relationship between well mixed non condensing GHG’s ( I hesitate to suggest WMNCGHG’s) and water. Water is a wild thing. Its vapor hangs out in the trophosphere, it has two phase changes within earth temperature range with attendant latent heat, and it has “feeds” back, forth, up down and sideways.

    The modelers have a notion that water is “feedback only” and that well mixed non condensers somehow manage water. In spite of their otherwise rigorous standards for physics, I have only found the supposed control mecanisim described as a “skin”, a “skeleton”, and a “relentless ratchet” (I like relentless ratchet the best).

    I can understand that CO2 mixes into the stratosphere up to te ozone inversion and could act as some sort of a lid and a backstop for any escaping photons, but whither the control?

    • trunkmonkey

      A new plow was invented, bumper crops filled the pantries, it was warm, everyone was ebullient. Cheap energy was available to all, along with better hygiene and medical care. More babies were conceived, and more survived. Life was good.

      But there were still many who did not have access to “cheap energy” (or clean drinking water and better hygiene and medical care). They conceived more babies since many would not survive to adulthood. Life was not so good, but there was hope that it would improve some day, as it already had for hundreds of millions of Chinese , Indians, etc.

      Then those who had all the good things decided it was time to reduce the supply of cheap energy for those who already enjoyed it and deprive those who did not have it yet of a supply of cheap energy in order to fight a virtual hobgoblin, which had been created by a handful of scientists and computer jockeys and promoted by another handful of politicians.

      Historians later chuckled about this strange epoch in human history (now referred to as the “golden era”), which ended abruptly as the planet cooled again, causing massive crop failure and famines.

      Max

    • trunkmunkey

      I meant sarcastically, actually.

      Correlation equals causation, just as sarcastically.

      CO2 causes violence, also meant in irony.

  21. My tuppence worth (in case anyone’s interested :-) ):

    1- Agreed

    2- On my current understanding- Agreed. I’ve seen lots of debate on this, but nothing that’s been explained sufficiently well (or clearly) for me to change my position on this.

    3- I’m afraid i haven’t come across this before so can’t comment.

    4- Agreed

    5- I’m hazy on this one, so I’ll have to disagree. I was under the impression that the natural component dwarfs the unnatural. Further, that there were issues with the identification of the specific carbon isotope used to attribute the anthropogenic signal.

    6- Disagreed- this point discounts any role of feedbacks (though i am disagreeing in principle i cannot discount positive feedbacks too).

    7- Agreed, but the warming is not a) unusual or b) significant- or at least not that we can tell with the data we have.

    8- Disagree strongly. “they both showed solar records without a rising trend in the late 20th century” – this is a fallacious argument. If you put a stove on to boil a kettle and you gradually increase the gas, the water temp will rise. Now, if you stop increasing the gas does the temp magically stop rising? No- not until equilibrium is reached.

    We don’t know the equilibrium point of the planet; therefore we cannot say that just because the solar output isn’t raising that it isn’t significant.

    9- Irrelevant, symptom not cause.

    10- Disagree; our level of understanding is not sufficient to attribute (with any level of significance) a value to this factor, though i would imagine it is at the lower side of the scale due to the incredibly stable climate at present.

    • Labmunkey – this is interesting, thanks.

      In my view, when its clearer who agrees with what and why, it makes the discussion more focussed.

      For what it is worth, I agree with the first 7 points.

      http://mitigatingapathy.blogspot.com/

    • Agree or disagree, a decent skeptic may wish to set out what to do about resolving further their position.

      I mean, if I agreed with any point ‘just because I think it sounds about right’ I’d be as bad as if I disagreed ‘just because it doesn’t smell right to me.’

      Of course, some claims are easier to do something about resolving than others, and some more important to do something about than others, and we’d generally prefer the chain of claims comprising a larger claim to be the one easiest and containing only those smaller claims important to the larger.

      So, some have stated there’s missing steps, or they don’t know enough about specific claims on this list.

      Seems to me important to enumerate, validate and verify those statements, and thence the resultant chain of claims.

      Me, I think most of this list can be substituted for the statements, “1.’) The climate is spatiotemporal chaotic in some measure; 2.’ The climate is not so chaotic as to be completely random; 3.’ Increased perturbations increase the randomness of chaotic systems; 5.’ CO2 represents a powerful source of perturbation; 6.’ Risk increases with randomness; 7.’ Risk need not be quantified to ascribe attribution and require compensation, mitigation and remediation.”

      See? My chain is two steps more efficient, and much, much easier to prove.

      • Bart, I believe that a scientist, skeptic or not, is very interested in agreement on quantified ranges of estimation of natural phenomena.

        Items #1 through #10 are decidely non-quantitative and quite fuzzy.
        If P then Q. If not Q….

      • Stephen Rasey

        Rutherford was very careful in his famous experiments to take detailed quantitative measures; his findings and exposition, however, can be stated clearly and unambiguously without reference to exact figures at all, and generally were described by analogy with throwing a ball at a brick wall and watching it pass through solid bricks.

        Nothing fuzzy there for all the lack of quantified ranges, and one of the foundations of modern understanding of the atomic nature of matter.

        So we’re offered a list with the fuzz edited out, as far as I can tell, here.

        I prefer details where details are germaine, not where they’re mere obfuscation.

        Please, by all means suggest expansions including those vital clarifying details you believe are missing, or specifically point to a place where lack of detailed quantified ranges excite doubt.

      • Ah, but then that’s a different matter altogether- for what it’s worth i think you’re right and i have two lists on this subject that i keep.

        One is on gaps in my knowledge, the other is on points that i’d need demonstrated for me to change my position.

        I’d be suprised if most sceptics didn’t do something similar.

      • Labmunkey

        Care to share your lists?

  22. On nr 8, note that Wolff made a clear distinction between the extent to which solar contributes to *variability* in the temperature record (disagreement) and the extent to which solar contributes to the *rising temperature trend* in the late 20th century (there *should be* agreement on that, at least between Lockwood and Svensmark, since they both showed solar records without a rising trend in the late 20th century.

    In your response, you seem to conflate the solar contribution to the temperature variability with its contribution to the warming trend.

    Overall, very good points and a worthwhile exercise by Wolff. Thanks for highlighting this.

  23. Surely a theory is judged only by the comparison of its predictions to independent observations or experiments. Presumably predictions into the future are significantly better than predictions into the past. If a theory cannot make readily testable predictions into the future, it doesn’t matter who agrees or disagrees with parts of the theory. No policy should be based upon an untestable theory.

  24. wayne arnold

    There may be warming for the last 50 years, but if 2011 stays relatively cool, Everyone will have to agree that the climate has cooled over the last 10years (GIStemp, hadley, UAH, RSS & NOAA/NCDC are all likely to have a Jan2002 to Jan2012 cooling trend)

  25. David Bailey

    We all agree about the infrared absorption spectrum of CO2, and I suppose the measurements of CO2 concentration in the atmosphere are correct, but honestly, not having made the measurements myself, I almost doubt that!

    Someone mentioned a 0.16 C per decade temperature rise. If you look at the way the ground measurements are collected, with instruments that are not even sensitive to 0.1 C, and then massaged by an assortment of algorithms that supposedly ‘correct’ for such things as an airfield being built round a measuring station, is this really established science (even forgetting the short time scale that it covers).

    I feel uneasy that there has been such a large percentage rise in CO2 concentrations, but honestly, I don’t think institutionalised science (funded asymmetrically) has done anything but add confusion.

  26. Too many incompetent experts, crosseyed from staring at bad theories and bad data. Do you agree the Earth’s surface radiates as a blackbody? There you go, that’s your problem right there. Hand me a wrench, I’ll fix it for you. WHAM! Now just keep a cold compress on that until you can think straight.

  27. What bothers me most about this list is its one-sided bias. It is not a list of basics that AGW proponents and skeptics might agree on, to find common ground, rather it is all about AGW. So we need a parallel list of skeptical basics. Some entries might include the following, for a start.
    S1. Climate changes naturally.
    S2. The mechanisms of natural climate change are not well understood.
    S3. The climate system includes many non-linear feedbacks.
    S4. These feedbacks are capable of producing counter intuitive behavior, surprises and unforced oscillations.
    S5. The climate is chaotic.
    S6. Chaotic behavior is intrinsically unpredictable.
    S7. We have no direct measurements of the major climate parameters over long periods of time.
    S8. The indirect measurements of climate parameters that we have are of unknown accuracy.

    • Latimer Alder

      S9:

      There is absolutely no evidence to suggest that the climate of the last 100 years was optimal for the planet and its organisms. And much anecdotal evidence to suggest that a warmer world will be, overall, a better world.

    • wayne arnold

      You can even break it done further (to individual mechanisms)
      Do we agree cloud feedbacks are positive?

    • WisconsinitesForGlobalWarming

      David, I very much enjoy and respect your posts, and this one is spot on IMO. If the pro-AGW crowd was truly interested in gaining agreement on what we agree on, then their list would include every item you mention. I, for one, would appreciate our host’s comments on S1-S8.

      In the absence of a balanced list of “items we agree on”, it appears to me that the lists put out are in fact some form of parlor game with a goal of entrapping skeptics into admitting they agree with AGW.

      Best,
      WFGW

      ps – Please send more global warming our way. May 25th in Milwaukee and it’s bloody cold (< 50 F)!!

    • David Wojik

      Too bad you were not there at Cambridge to direct the discussion beyond its myopic fixation on AGW,

      Your S1 through S8 should have been proposed to the group to see who agrees/disagrees.

      I would have agreed with all 8 points (as I think most of those present would also have).

      It would be interesting to see whether or not Judith Curry would also agree with all 8 points. From earlier posts on this thread I think she is in basic agreement with most, if not all.

      Judith – can you take a stand on these 8 premises raised by David?

      Max

    • David Wojick 5/25/11 at 7:04 am, Agree on

      S1: Agreed!

      S2: Disagree. Climate is driven by the Sun, the energy being primarily absorbed by the ocean, which distributes the heat and smoothes the temperature response over a century or so. The Sun, however, is the weak link, being not well enough understood to be predictable on climate to geological time scales.

      S3: Climate models are linear or not, not the climate system. Linearity is a mathematical property, and mathematics is man made and does not exist in nature.

      S4: Disagree. The feedbacks are easily understood, especially in proportion to their strength. Modeling some of them in IPCC’s radiative forcing paradigm with no flow variables is a different story, and some may require inventions like super-parameterization in that domain.

      S5: Disagree. The climate is neither chaotic or non-chaotic. Chaos is a property of models, not of the real world. The real world has no initial conditions, for example. Secondly, Earth’s climate is quite predictable and in a narrow band, given enough tolerance on the accuracy, and assuming the THC and Sun models do not become chaotic.

      S6: Quibble. Unpredictability in chaos is by definition.

      S7: Agree, but not with the implications. Climate is a thermodynamic problem, and thermodynamic variables are macroparameters, not directly observable. The major components of climate, the global average surface temperature and global average albedo are examples. This does not imply that a thermodynamic model has no solution.

      S8: Disagree. While the accuracy of climate parameters may still be lacking an accuracy computation does not mean that the accuracy is unknowable. For example, the Global Average Surface Temperature anomaly is about 3ºC ± 1.5ºC in the warm state, and -9ºC ± 1.5ºC in the cold state. The Global Average Albedo is about 0.3 ± 0.05. If anyone wants to quibble about the accuracies cited, just increase their value until they quit complaining. An accuracy is almost always possible.

      • Math may or may not be man made (as opposed to discovered) but nature is mathematically describable. That is, mathematical statements about nature are either true or false. I have 7 horses not 6. So some processes are linear while others are not, some chaotic, some not. Just as some things are red and some not, even though red is a man made word. This is called intentionality, the ability of language to be about things in the world. We do not understand it but we know it works. Science is the mathematical description of the world based on observation.

    • I don’t disagree with any of these statements. However, this list needs to be considered with Bishop Hill’s list (well actually a better list would be better). S1-S8 do not any any way preclude AGW, but they certainly make the point that deciphering an AGW signal and understanding its implications is not simple.

      • Judith

        Thanks very much for taking a stand on David’s list. Your agreement with his points is a pretty clear signal.

        Actually, I agree with you that BOTH lists should have been included by Dr. Wolff, with David’s as a more general preamble (climate variability in general) to the more specific list (AGW impact on climate).

        While your response to David’s list does “not in any way preclude AGW” it does relativize it and (in your words) “make the point that deciphering an AGW signal and understanding its implications is not simple”.

        To me this sounds like “uncertainty” (with a capital “U”) and quite different from the level of confidence one finds in the IPCC AR4 WG1 SPM report (not to brand you with Lemonick’s “h” word).

        Max

      • “not disagreeing” is not the same thing as “agreeing.”

      • WisconsinitesForGlobalWarming

        I will echo Max’s thanks to Dr. Curry for taking a stand on S1-S8.

        I agree, these aren’t the only statements regarding agreement we should be discussing, but David’s point was so well made.

        Time to reopen the discussion of Cambridge with a complete set of questions.

    • I think the point is to stop wasting time on what all but the crackpot fringe agree upon, thereby spending time more productively pinpointing the precise points of controversy. It’s a waste of everyone’s time to hash over whether or not CO2 is a greenhouse gas; and politically, it hands a weapon to the CAGW warriors when they can wave around that “Glenn Beck said so and so”.

      This is why it was Bishop Hill who chose to pursue this. Joe Romm is as happy as a clam to allow the impression to continue that large numbers of skeptics deny the greenhouse effect. All of that ambiguity plays into the hands of the activists.

  28. I am about to try and do what is clearly impossible; explain something that I do not really understand. But I balk at 1. Everyone in the room agrees that CO2 does absorb infrared radiation, as observed in the lab.

    This is a trap. The proponents of CAGW perpetuate a myth; that it is possible to conclude from science, physics, what happens when you add more CO2 to the atmosphere, merely by looking at what happens to the absorption of infra-red radiation. If you start down this line of reasoning, you come to the absurdities of forcings and feedbacks, and then come to 10, where there are major disagreements. But the process looks like it is physics, when it really isn’t. This is why the first “agreement” is so important.

    This is what happens when a proponent of CAGW asks the questions. I would suggest that the first order of business is something more like the following. The way the atmosphere works is a combination of conduction, convection, the evaporation and condensation of water, and the absorption and emission of infra-red radiation. No-one understands, in detail, the way these processes act and interact. Can we agree that physics cannot tell us what happens when we add more CO2 to the atmosphere from current levels, until we know, in much more detail, how the atmosphere works?

    My answer to this would be a very definitive YES. I would be interested in how anyone who claims that, without knowing the detailed physics, we can still say something useful about CAGW, can justify that answer.

    • Joe Lalonde

      Jim,

      Science settled itself with generalized physics of “it’s okay to NOT be exact”.
      This then puts all of science into the same frame of not looking deep enough for answers.
      A lab does not produce all the same factors or energy interactions that the atmosphere produces. CO2 is mostly concentrated at the planet level while many other gases are above this plus the motion of a rotating planet and rotating sun produces many different deflections. This is without a single cloud.
      Density of gases are different in different regions from warm or cold gases.
      Etc,etc,etc.

    • Kent Draper

      Jim, do you know if it has ever been proven conclusively that CO2 increased first or warming increased first? In other words, did the increase of CO2 proceed the warming or did the warming proceed the increase of CO2? Would be really handy for my thought process to know this.
      Kent

      • I am no expert on this issue, but I have always understood that the ice core data suggests that temperatures rise first, and CO2 follows some 800 years later. But dont quote me.

      • Jim Cripwell

        That’s what the Vostok ice core data showed (CO2 lagged temperature by several hundred years).

        http://www.daycreek.com/dc/images/1999.pdf

        Moreover, there are at least 3 periods in this record where temperature started dropping when CO2 was at its peak and 3 periods when temperature started rising when CO2 was at a low point. A real dilemma for those postulating CO2 as a “driver” of temperature.

        CO2 was definitely not “driving” temperature in this record no matter how many rationalizations are made to try to show this.

        Max

      • Jim Cripwell

        Further to the geological atmospheric CO2 record

        From: R.A. Berner and Z. Kothavala—GEOCARB III: “A revised model of atmospheric CO2 over Phanerozoic time” http://earth.geology.yale.edu/~ajs/2001/Feb/qn020100182.pdf

        There appears to have been very high early Paleozoic levels of CO2, followed by a large drop during the Devonian, and a rise to moderately high values during the Mesozoic, followed by a gradual decline through both the later Mesozoic and Cenozoic.

        RCO2 = the ratio of mass of CO2 at time t to that at present (t = 0)

        Million years BP RCO2 ppmv
        500 27 7560
        450 16 4480
        400 12 3360
        350 3 840
        300 1.5 420
        250 7 1960
        200 5 1400
        150 7 1960
        100 4 1120
        50 2.5 700
        0 1 280

        Sort of raises questions regarding Hansen’s postulated 450 ppmv “dangerous level” at which irreversible “tipping points” in our climate will occur.

        Max

      • Jim Cripwell

        Have reposted geological atmospheric CO2 table from Berner and Kothavala with spacers (—-) to make it easier to read:

        RCO2 = the ratio of mass of CO2 at time t to that at present (t = 0)

        Million years BP—-RCO2—-ppmv
        500—- 27—-7560
        450—- 16—-4480
        400—- 12—-3360
        350—- 3—-840
        300—- 1.5—-420
        250—- 7—-1960
        200—- 5—-1400
        150—- 7—-1960
        100—- 4—-1120
        50—-2.5—-700
        0—-1—-280

        Max

      • Kent Draper

        Thanks Jim and Max, appreciate your ability to find this info as it really helps if you know what to ask before you go looking :) Saves a ton of time. If you ever need to know anything about process control, let me know :)
        Kent

  29. J,
    Concerning Chicago, it seems a rather big deal to me. Certainly symbolically. From the NYT’s :

    “Public alleyways are being repaved with materials that are permeable to water. The white oak, the state tree of Illinois, has been banned from city planting lists, and swamp oaks and sweet gum trees from the South have been given new priority. Thermal radar is being used to map the city’s hottest spots, which are then targets for pavement removal and the addition of vegetation to roofs. And air-conditioners are being considered for all 750 public schools, which until now have been heated but rarely cooled. ”

    The basis for these measures?

    “The forecasts, while not out of line with global predictions, shocked city planners. If world carbon emissions continued apace, the scientists said, Chicago would have summers like the Deep South, with as many as 72 days over 90 degrees before the end of the century. For most of the 20th century, the city averaged fewer than 15.

    By 2070, Chicago could expect 35 percent more precipitation in winter and spring, but 20 percent less in summer and fall. By then, the conditions would have changed enough to make the area’s plant hardiness zone akin to Birmingham, Ala. ”

    I love the specificity. It’s based on nothing but wild conjecture. The mad scientists are finally beginning to run the show.

  30. I agree with most of Dr Wolff’s points but he is completely wrong on 3. At least, in the anology of adding ink to water there certainly is saturation. So either he is wrong or he is using an incorrect analogy.

    • Whether the absorption by CO2 saturates or not, is in part a semantic question: What do we mean by saturation?

      One way of defining saturation is by saying that anything deviating from linear effect shows saturation. In this sense everybody is likely to agree that it saturates.

      The other extreme that many may accept is that saturation means that the transmitted radiation approaches asymptotically a constant value, perhaps in accordance with Beer-Lambert law which applies to monochromatic radiation. Here I would expect more disagreeing voices, while most would agree that this is not the correct description for CO2 in the Earth atmosphere.

      Most would probably accept that the dependence on concentration is neither linear nor the exponential of Beer-Lambert law, but actually close to logarithmic over a rather wide range of concentrations, which covers well enough all scenarios presented for the future. This alternative deviates from linear towards saturation, but grows without limit as far as the logarithmic behavior is valid even as rough approximation. There will be a saturation at unrealistically high concentrations, but as those concentrations are impossible to reach, that’s not really relevant.

      In any case saying that there is no saturation, is not the simple truth, but requires qualifications. The real question concerning agreement is:

      Do people accept that the logarithmic dependence on concentration is a satisfactory approximation over all concentrations of concern?

      • There are a few curves and calculations given here – http://brneurosci.org/co2.html The approximately logarithmic progression limits temperature increase at what are achievable – but quite scary – concentrations above 800 ppm.

      • Chief

        You’ve just posted a link to a pretty compelling and comprehensive paper on the GHE of CO2, which concludes that the 2xCO2 climate sensitivity with all feedbacks is at most 1.02°C to 1.85°C: This assumes that all observed 20th century warming was caused by CO2 (1.85°C) or all GHGs (1.02°C).

        This shows that doubling CO2 over its current values should increase the earth’s temperature by about 1.85 degrees C. Doubling it again would raise the temperature another 1.85 degrees C.

        Since these numbers are based on actual measurements, not models, they include the effects of amplification, if we make the reasonable assumption that the same amplification mechanisms that occurred previously will also occur in a world that is two degrees warmer.

        If we want to include other greenhouse gases, such as methane, in the calculation, we need to use the “effective” CO2 concentrations instead. These effective CO2 numbers are less solid than the CO2-only numbers, but the best estimates are that effective CO2 increased from 305 to about 450 ppm during the 20th century [The Satanic Gases, p.36.]. Using these numbers, k becomes 0.6823 and the predicted ΔT becomes 1.02 degrees.

        These estimates assume that the correlation between global temperature and carbon dioxide is causal in nature. This remains to be proved. Therefore, the 1.02 and 1.85 degree estimates should also be regarded as upper limits.

        This estimate uses the observed 1900-2000 increase in temperature, the observed 2000 atmospheric CO2 level (Mauna Loa) minus the estimated 1900 CO2 level (Vostok), and (in the second case) estimated CO2 equivalents of other GHGs, without the assumption of any GH warming being “hidden in the pipeline”.

        The author then also projects that it will take several centuries to double current CO2 levels.

        IPCC assumes an exponential growth, even higher than the exponential growth rate actually seen most recently or over the entire Mauna Loa record (both around 0.42% CAGR); on this basis we could reach 2X today’s level (~780 ppmv) by 2180 (and ~560 ppmv or 2x the estimated “pre-industrial level” by 2100).

        Population increased by 1.7% CAGR from 1960 to 2000, but is expected by the UN to slow down to a CAGR of 0.3% over the 21st century, so it seems highly unlikely that CO2 will continue to grow exponentially, as IPCC model scenarios assume.

        The paper concludes:

        Although carbon dioxide is capable of raising the Earth’s overall temperature, the IPCC’s predictions of catastrophic temperature increases produced by carbon dioxide have been challenged by many scientists. In particular, the importance of water vapor is frequently overlooked by environmental activists and by the media. The above discussion shows that the large temperature increases predicted by many computer models are unphysical and inconsistent with results obtained by basic measurements. Skepticism is warranted when considering computer-generated projections of global warming that cannot even predict existing observations.

        All in all the paper you cited, Chief, tells us that AGW is nothing to get too excited about.

        How do you see this?

        Max

  31. Joe Lalonde

    Judith,

    The complexity of many area’s of science on this planet is mind boggling but we have compensated this with generalized theories that science has made to fit.
    To be exact is to understand ALL of the relationships of the differing densities(warm and cold), understand the magnificent efficiency of the system this solar system has mechanically created with the sun and planet. This in turn shows how gravity is achieved by a complex system as well as why planets NEED to be round.
    Compression is NOT considered even though we live in a compressed atmosphere. Circular motion is NOT considered as formulas and mathematics in a lab have NOT considered it.

    So unless we open science to new ideas of research, the same stifling mistakes WILL continue until all of science is reduced to being ignored due to their failures.

  32. Bad Andrew

    Anyone who takes more than a second to think about this agreement stuff understands that none of it has any scientific value.

    Who ever said rope-a-dope upthread…

    Andrew

    • Shedding light on questionable acts by questionably competent “scientists” should contribute *great* value to science. Having followed your trolling for a while, I can understand why you might prefer darkness.

  33. Bad Andrew

    “Shedding light on questionable acts by questionably competent “scientists” should contribute *great* value to science.”

    Mrmethane,

    You are incorrect. Questionable acts by questionable scientists only screams “this isn’t science”. Science is evidence, evidence, evidence and data, data, data. Appealing to agreement between to political opponents is a political act.

    Andrew

  34. Rob Starkey

    This posting will probably generate a significant number of comments, (which should allow Judith more time to concentrate on her DoD work until that is completed…lol)

    I largely agree with her summary.

    I add that the real issue impacting people would be a point 11- “what policies should be enacted by individual nations in response to points 1-10.” I suggest that what makes sense for one nation will not makes sense for another. IMO many of the proposed policies contemplated by western countries are just pointless attempts to demonstrate that “we are trying” vs. actually doing things both environmentally and economically sound.

    Even if there was general agreement on points 1-10, I suggest that the overall benefits of emitting CO2 today, and for decades to come; outweigh the potential harms to humanity.

  35. Re #8

    The influence of solar changes are not confined to the decade’s in which the changes occurred any more than CO2 changes are.

    If it warms for any reason the feedbacks kick in and may last 100 years or more. Solar increases certainly happened since records began around 1860.

    http://sidc.oma.be/html/wolfaml.html

    To claim that CO2 feedbacks take hundreds of years but solar influences all happen immediately makes no sense.

    The effect of solar increases would be a long ramp with whatever current influences there re superimposed. This ramp appears to be around 1/2 ° C per century. Since the ramp started when CO2 emissions were negligible I doubt CO2 caused the ramp.

    Superimposed on this there is a 60 year PDO cycle which is almost certainly responsible for the 1978 to 1998 warming since the PDO switched positive around 1978 and remained positive until 1998 and the resultant preponderance of El Nino’s is well documented.

    El Nino’s/La Nina’s

    http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml

    PDO

    http://rankexploits.com/musings/2008/nasa-says-pdo-switched-to-cold-phase/

    Conclusion: It should have warmed without any CO2 from 1978 to 1998. The cooling from 1940 to 1978 can easily be explained by the preponderance of La Nina’s during this period. [No aerosols need apply !]

    The overall warming is very slow if you subtract El Nino/La Nina driven short term cycles and may be almost entirely natural.

  36. JCurry 5/24/11 What we agree(?) on

    Wolff #4. Agreed that the over filtered published results from MLO, absent any approximation to raw data, shows a major increase in atmospheric CO2 over the last half century. Disagree sans evidence that it is global and not regional. Agree with IPCC formula that CO2 is short lived, and not with its conjecture that it is long lived and well mixed.

    Wolff #5. The cause of the increase at MLO is over 90% natural due to increase in SST. Human contribution is 3% to 6% in proportion to IPCC’s published estimates for ACO2 flux vs. natural CO2 flux. No mechanism like the Revelle buffer factor conjecture exists to bottleneck ACO2 in the atmosphere while allowing nCO2 to flow unimpeded at 15 times or more the rate of ACO2. The human fingerprints on the rise in MLO CO2 are baldly manufactured by investigators. The notion that equilibrium chemistry applies to the surface ocean is fantastic.

    Wolff #7. Agreed that warming is occurring, but on climate scales of ≥ 30 year trends.

    Wolff #8. Agreed: we don’t agree on the cause of the warming. It is the Sun. Anthropogenic causes are all positive, but each too small to be measured.

    Wolff #10. Much more than agreed. The major feedback in the climate system is cloud albedo in the warm state and surface albedo in the cold state. IPCC admits cloud feedback is the greatest source of uncertainty in its models, which have yet to represent dynamic feedback. Cloud feedback is fast and positive in response to solar radiation. It is the diurnal burn off effect, and surely the major cause of the measured Stott, et al. (2003) (ignored by IPCC on other grounds) and Tung, et al. (2008) solar amplification yet to be represented in the GCMs. Cloud feedback is slow and negative in response to surface temperature, the Clausius-Clapeyron effect, mitigating warming from any cause. The slow cloud albedo effect reduces the GCM correspondingly open loop climate sensitivity by a factor of 3 to 10.

    The Stott/Tung amplification, which would be even greater measured against the Wang, et al. (2005) model instead of the earlier Lean model, is not the Svensmark effect. The atmosphere is not CCN limited. It has an average surplus of CCNs or INs, accounting for the reliable cloud formation in response to humidity and temperature, and accounting for the lack of evidence of a cloud chamber effect. The correlation of temperature with the Sun is due to cloud reaction to solar radiation, but not significantly coupled to galactic cosmic ray modulation, and that correlation lags between a half and one and a half centuries because of slow ocean transport of heat.

    Having a categorical list is most helpful. It tends to clarify the massive confusion here over what constitutes a null hypothesis.

  37. 1. Everyone in the room agrees that CO2 does absorb infrared radiation, as observed in the lab

    Agree with Judith: ~99.99%. But many other things do as well.

    2. I think everyone in the room agrees that the greenhouse effect (however badly named) does occur in practice: our planet and the others with an atmosphere are warmer than they would be because of the presence of water vapour and CO2.

    Not convinced. Water vapour – highly likely (~99.99%), CO2 – maybe not for many possible reasons. It is probably very complex and there might be many black swans.

    Furthermore, there is increasing evidence that rising atmospheric CO2 content (in ppm) DOES NOT (or at least not significantly) drive up the “GTA”. And taking into account that rising global temperature DOES (~99,99%) causes the CO2 content to rise, it is very unlikely that CO2 itself causes the temperatures to rise significantly – there must be negative feedbacks or limiting effects of some sort, otherwise small disturbances are amplified and the system becomes very unstable.

    3. The greenhouse effect does not saturate with increasing CO2.

    Don’t know. There must be some limiting or “saturating” effect to CO2 warming potential, if there is any significant CO2 gw potential.

    4. It seemed that everyone in the room agreed that the CO2 concentration in the atmosphere has risen significantly over the last 200 years

    200 years: very likely (~99.99%)

    5. Almost everyone in the room agrees that this is because of anthropogenic emissions (fossil fuels, cement production, forest clearance). We did hear Ian Plimer arguing that volcanic emissions of CO2 are more important than most scientists claim.

    Anthropogenic influence (ALW maybe even some global) is likely (200 years). CO2 is only significant since ~1950s.

    6. I then suggested that if we agree all these statements above, we must expect at least some warming.

    ??? I expect cooling.

    7. I think everyone in the room agrees that the climate has warmed over the last 50 years, for whatever reason: we saw plots of land atmospheric temperature, marine atmospheric temperature, sea surface temperature, and (from Prof Svensmark) ocean heat content, all with a rising trend.

    Agree, over the last 50 years we had a rising trend, but IMO mostly a bit exaggerated/overestimated. This slightly rising trend can change quickly to flat and then to falling.

    8. We probably don’t agree on what has caused the warming up to now, but it seemed that Prof Lockwood and Svensmark actually agreed it was not due to solar changes, because although they disagreed on how much of the variability in the climate records is solar, they both showed solar records without a rising trend in the late 20th century.

    Regarding climate changes at this timescale, it’s mostly the sun. Solar cycle length is a very good proxy.

    9. On sea level, I said that I had a problem in the context of the day, because this was the first time I had ever been in a room where someone had claimed (as Prof Morner did) that sea level has not been rising in recent decades at all. I therefore can’t claim we agreed, only that this was a very unusual room. However, I suggested that we can agree that, IF it warms, sea level will rise, since ice definitely melts on warming, and the density of seawater definitely drops as you warm it.

    Agree, if it warms, sea level will rise, but it started cooling and you can already see the effect. Sea level will start falling very soon (few years).

    10. Finally we come to where the real uncertainties between scientists lie, about the strength of the feedbacks on warming induced by CO2, with clouds a particularly prominent issue because they have competing effects that are hard to quantify. I suggested to the audience that we could probably agree that the likely range of warming from a doubling of CO2 was 2-4.5 degrees C (which is actually the IPCC range). This was the first time I really got any dissent, so I then asked whether we could all agree on at least 1 degree (implying no positive feedbacks at all, even from increased water vapour and sea ice loss). I got one dissenting voice for that, but there wasn’t a chance to find which of the preceding statements he had disagreed with (it would be necessary to disagree somewhere up the line to be consistent with dissenting on this one).

    Have patience. We live in interesting times. If the cooling continues, we might see falling CO2 levels very soon.

    • “I think everyone in the room agrees that the greenhouse effect . . .”

      I am baffled as to why people keep saying this, even though the comments on this thread alone clear demonstrate that many people do NOT agree to the basic physics of the greenhouse effect. So why do people like Dr. Curry keep claiming that “skeptics” have more moderate views than is actually the case?

      I think the explanation can only be loneliness. There are a tiny number of scientifically literate “skeptics,” who argue mostly, as Dr. Curry alludes to, about the the magnitude of the warming and its likely effects. There are a huge number of scientifically illiterate “skeptics” as is amply demonstrated by the comments above. Blurring the distinction between the two is a way to evade the great “skeptical” paradox: Denial of the theory of AGW, insofar as it is rational, is rare, and insofar as it is not rare, is not rational.

      • “There are a huge number of scientifically illiterate “skeptics”

        Robert,

        Are you suggesting that people who don’t understand AGW theory should believe it anyway? Or should they withold believing it until they understand it? Which position should rational people have?

        Andrew

      • Are you suggesting that climate “skeptics” are aware of their ignorance of science and are generally skeptical as a result?

        Can you give me an example?

      • Robert,

        Why don’t you answer the question posed?

        Andrew

      • Because it’s unclear. Why don’t you answer my question?

      • Robert,

        I think it was obviously clear and you are suddenly obtuse when we know you are oh so smart. ;)

        Andrew

      • So you are able to provide an example of what you mean? That’s unfortunate. I guess you really are more interested in insults and sarcasm. If you decide it get serious, I’ll be around.

      • Correction: not able to provide an example of what you mean.

      • Ask (insincerely) and ye shall receive, Robert.

        I have a friend who mentioned AGW in a conversation. I asked her what she knew about it, and she said she hadn’t really looked into it. What should her rational position be on the subject, Robert?

        Andrew

      • She is clearly not a “skeptic.” She may or may not be scientifically illiterate, which is different from not knowing the particulars of a given discourse. Hence she in no way resembles the scientific illiteracy on display above.

        How she should proceed would depend on the time she has to devote to the subject. It’s OT in terms of this discussion.

      • Why do AGW believers like you only think one climate variable has changed since the LIA (or 20th century or 1950 depending on when AGW supposedly starts)

        By the way … which year did AGW start?

      • Bruce, could you please provide the following, in order that I might understand and answer your question:

        *Define “AGW believer.”
        *Prove that, as you assert, “AGW believers” “only think one climate variable has changed since the LIA”
        *Prove that I am an “AGW believer” and that I think “one climate variable has changed since the LIA”

        Thanks!

      • Bad Andrew

        Evidently Robert may argue in generalities, but no one else can.

        Andrew

      • I’m sorry I’m not able to relieve you of the burden of clarifying your ideas.

      • Bad Andrew

        Robert,

        Can you clarify yours while we are at it?

        What exactly is a “skeptic”? Please be specific.
        What exactly are the components and evidence for and against AGW theory?
        What constitutes “denial” of that theory?
        What are the identifying characteristics of “loneliness”?

        This is good enough for starters, I suppose.

        Andrew

      • “What exactly is a “skeptic”? Please be specific.”

        Real, or the climate variety?

        “What exactly are the components and evidence for and against AGW theory?”

        Shouldn’t you have researched that before you developed such strong opinions on the subject?

        “What are the identifying characteristics of “loneliness”?”

        How cute you pretend not to know.

      • Bad Andrew

        Robert,

        “Real, or the climate variety?”

        I don’t know, you didn’t really specify in your comment.

        “Shouldn’t you have researched that before you developed such strong opinions on the subject?”

        I’m trying to find out what *YOU* think.

        “How cute you pretend not to know.”

        I do know. But you didn’t define it in your comment.

        Andrew

      • “I’m trying to find out what *YOU* think.”

        Then why ask “What exactly are the components and evidence for and against AGW theory?”?

        Surely those exist independent of what I believe. What issues in particular did you want to know my beliefs regarding? And how does it relate to the topic?

        “I do know. But you didn’t define it in your comment.”

        If you know what loneliness is, and I know what it is, then I expressed myself clearly and I think we’re fine.

      • Bad Andrew

        Robert,

        “Then why ask “What exactly are the components and evidence for and against AGW theory?”?”

        Because I want to find out what you think they are.

        “What issues in particular did you want to know my beliefs regarding? ”

        AGW Theory and the denial of it and what a “skeptic” is.

        If you know what loneliness is, and I know what it is, then I expressed myself clearly and I think we’re fine.

        Good on that one. ;)

        Andrew

      • “Because I want to find out what you think they are.”

        The IPCC report has some good information and many references. I recommend you start there.

        A climate “skeptic” is a person who calls themselves a climate skeptic. Their beliefs are varied and often contradict each other.

      • Guys, your bickering is positively matrimonial. Please. Get a room.

        ;-)

      • Bad Andrew

        Josh,

        You’re just jealous.

        This is a *real* argument, and Robert is schooling me with his stragentum argumentum, can’t you see?

        Andrew

      • WisconsinitesForGlobalWarming

        Based on this *argument* I’d like to propose two new items we can all agree on:

        SA1: there is very little agreement between the sides.
        SA2: Robert is a pompous ass.

        OK, so maybe we can’t agree on #2, but it felt sooooooo good to type.

        WFGW

      • Oh I see, schooling you with his stragentum eh. Well, I will leave you to it then.

      • Robert, I think you are an AGW believer because you put skptics in quotes.

        Which year did AGW start? If you can’t or won’t define a start date, then it implies you don’t really believe in AGW.

        Which climate variable do you think are important and where is IPCC incorporating the data for them ?

        I think bright sunshine hours are way more important than CO2 and it has changed over the 20th century. Even a few extra minutes of sunshine a day can swamp any claimed W/m^2 effect of Co2.

      • “Robert, I think you are an AGW believer because you put skptics in quotes.”

        At least I know how to spell it.

        “Which year did AGW start? If you can’t or won’t define a start date, then it implies you don’t really believe in AGW.”

        Really. How so?

        “I think bright sunshine hours are way more important than CO2 and it has changed over the 20th century. ”

        Right, because you don’t know anything about science. So you have this kookie fixation on a non-issue. You see how that works?

        But by all means, prove me wrong: write up your stunning “bright hours of sunshine” theory, send it to Nature, and send me a copy. Good luck!

      • If you can’t name a date you don’t actually think AGW has started or you just want to reserve the right to pretend natural variablity is AGW.

        Come on bobby … pick a start date for AGW. Maybe there is a peer reviewed paper naming a particular date it started?

        What kind of “theory/scam” can’t even tell you when something started to happen?

        Wild has already written up his papers on global dimming and brightening. So have others. The IPCC and so-called “scientists” ignore it.

        I have many examples like the one below:

        Just for the heck of it I looked at Heathrow’s Sunshine Hours which they started collecting in 1957:

        Decade Sunshine Hours Total
        1960s – 14555.7
        1970s – 15118.6
        1980s – 15264.4
        1990s – 16801.9
        2000s – 16776.8

        http://www.metoffice.gov.uk/climate/uk/stationdata/heathrowdata.txt

        Not a small change. 2300 hours or so per decade change from the 1960s to the 1990s/2000s.

        230 hours per year more bright sunshine.

        (I know you are fixated on CO2 and will ignore evidence to the contrary like a good cult member, but others might be interested)

      • “If you can’t name a date you don’t actually think AGW has started or you just want to reserve the right to pretend natural variablity is AGW.”

        That’s the same assertion again. Why so?

        “Come on bobby …” Sorry widdle brucie. Your whining and pleading are not going to help your case. Nor is ranting about “cult members” or “so-called ‘scientists.”

        Just wipe the spittle off your chin and explain what you want to know and why, like a rational adult.

      • The concept of falsifiability eludes you — not unexpectedly.

        If your “science” can’t even agree on some date that man made Co2 started affecting climate there is no theory to be skeptical about.

        It appears to just be a bunch of unfounded assertions designed to raise grant money.

      • Man-made CO2 started doing the climate shortly after the beginning of man-made CO2: a very long long time ago.

      • Rob Starkey

        Robert—

        I suggest that the majority of the commenter’s at this site accept the basic physics of the greenhouse effect. It is the relative impact of that effect (as Judith summarized) that is correctly questionable. I am highly skeptical of many of the positions of Hansen, etc.

        Yes, there are many people who do not believe the basic physics, but there were also many people who believed that the world would end on 5/21. Statistically, that would seem to be expected from a large sample.

        What is frustrating is that AGW “believers” frequently like to generalize the positions of all who do not believe that the case for immediate, drastic actions has been supported scientifically or economically. When I read the positions of most who believe AGW is a dire problem, imo; they clearly do not understand the details of the science or the economics, but they do let that dissuade them from arguing.

      • “I suggest that the majority of the commenter’s at this site accept the basic physics of the greenhouse effect.”

        I think if you review the comments above, you will find that many do not.

        “What is frustrating is that AGW “believers” frequently like to generalize the positions of all who do not believe that the case for immediate, drastic actions has been supported scientifically or economically.”

        I’m sure that just as in any debate, people will tend to focus on the most embarrassing and ignorant things the other side has said.

        The only countermeasure, I’m afraid, is to clearly distinguish yourself from scientifically ignorant/dishonest “skeptics.”

        I think you will find that if you acknowledge that many, perhaps most of the self-identified “skeptics” are ignorant of basic science and dispute it only for political and ideological reasons, people will be less prone to associate their excesses with you.

        The project of stating areas of agreement is a step in this direction.

  38. 3. The greenhouse effect does not saturate with increasing CO2.

    JC comment: a slightly complicated issue, but one that has been more than adequately dealt with in the published literature and the technical climate blogosphere (e.g. here).

    Do people accept that the logarithmic dependence on concentration is a satisfactory approximation over all concentrations of concern? – Pekka Pirilä

    This is an enormous issue and nowhere near an agreement? If the GH effect due to CO2 is logarithmic, then adding more isn’t going to have a measurable effect, but the referenced article definitely states otherwise. Where is the agreement? Is going from 300ppm to 400ppm going to have a measurable effect or not? If it is, how great an effect? Where is the science on this?

    And why are we ignoring the elephant in the middle of the room? Aren’t we agreed that climate scientists have been cheating? What happened to the leaked emails? What about McIntyre and the Antarctic temps? The 40 years of discarded tree cores, Montford and the HSI? Shouldn’t someone at least mention the fact that climate scientists have been caught cheating?

    • “Aren’t we agreed that climate scientists have been cheating?”

      No, Dr Wegman is a statistician, not a climate scientist. Glad we clarified that!

      • Thank God! Climate “Scientists” know nothing about statistics … except for the new unique fabricated methods that only work on one special tree in Yamal.

      • Sorry, the only one “fabricating” is your friend, the plagiarist.

        But thanks for playing. ;)

      • Wegman’s work stands up. Since you never say anything, the same can’t be said of your drivel.

        “Lost in the recent controversy over Said et al 2008 is that the Climategate documents provided conclusive evidence of the hypothesis originally advanced in the Wegman Report about paleoclimate peer review – that members of the Mann “clique” had been “reviewing other members of the same clique”.”

        http://climateaudit.org/2011/05/23/climategate-documents-confirm-wegmans-hypothesis/

        The corruption of “science” by so-called “scientists” like Mann et al is quite sad. You fit in.

      • Wegman’s committee agreed under oath with the M+M discrediting of Mann’s “schtick” on the basis of flawed statistical methodology a.o., concluding that the claim of unusual late 20th century warmth could not be supported by the “schtick”.

        The NAS panel agreed under oath with the conclusions of the Wegman committee.

        Read Andrew Montford’s book, if you want a detailed “blow by blow” account.

        Max

  39. Dr. Curry
    I keep heckling from the sidelines, while I am working on the ‘Natural climate change’ article, which is not related in any respect to the solar variability or even less to the magnetic fields.
    However, I suggest that anyone who is seriously interested in the natural climate change should look at this graph of the Loehle’s global temperature reconstruction:

    http://www.vukcevic.talktalk.net/LL.htm

    What we agree?
    -Temperature reconstructions are not perfect, the Loehle’s one is no different, but many think it is better than the average.
    – Earth’s magnetic fields (GMF) reconstructions are far more reliable since the paleo-magnetic field frozen in samples is actually measured, and in for the last 300+ years compared to the actual, verifying the values obtained. Two magnetic reconstructions used here are accepted as the best available.
    The graph refers to the rate of change in the geomagnetic field in the Arctic.
    – Some (not all) may agree that similarity between two is too close to be ignored.
    What is the reason?
    Svensmark’s hypothesis on galactic cosmic rays (GCR)-cloud formation, may be an answer, but not the ‘albedo’ effect part.
    Solar scientists suggest that GCR are modulated by the solar magnetic field (from a cycle max to a cycle min) to a depth of 25%, and then again by the Earth’s magnetic dipole to a further depth of 50%.
    It is assumed that dipole is loosing strength almost evenly, giving a flat rate of change. However this is not case in the Arctic, on a multidecadal time scale the Arctic’s GMF varies in a reverse proportion to the solar field.
    This would mean that the Svensmark’s albedo hypothesis is working wrong way in the Arctic area, e.g. the Arctic’s field was very strong at the time of Maunder min, which would mean low GCR, less cloud, warmer climate, but that was not the case, it was the depth of the Little Ice Age.
    So what is going on?
    Most of GCR end up in the polar area, while only strongest get through to the equatorial regions. If Svensmark is correct that GCRs increase cloudiness, than the largest effect will be at poles. Since in the last decades GMF was weakest (the solar field was strongest), than increase in cloudiness will be higher and consequently cooler Arctic, exactly opposite to what Svensmark suggests.
    Increased albedo in the Arctic’s autumn, winter and spring, as well as during summer nights has no effect (low or no insolation), but higher cloudiness will act as a ‘heat trap blanket’ keeping the arctic atmosphere warmer and at the same time shortening the sea ice formation season, as is the case now compared to the past centuries.
    In the summer’s daytime, albedo will reduce Arctic warming, but only in the areas which are not covered by ice or snow.
    Hence: Increased solar activity= reduced GMF=more GCRs =more cloud= less heat lost= warmer polar circle region.
    In this context the GMF – GCR relationship works in the same direction as TSI but on a much longer multidecadal time scale, the individual solar cycles modulation is smoothed by the inertia of GMF.
    Very speculative, but possible if GCRs do affect cloud formation.
    High correlation between the Arctic’s magnetic field and the Arctic’s temperature anomaly may be a direct verification of the above ‘heat trap blanket’ effect:

    http://www.vukcevic.talktalk.net/NFC1.htm

    In case you do wonder, no this is not substance of my forthcoming article, which is about half done

  40. Bad Andrew

    I’d like to complain to the moderator. Robert and I are trying to have a legit conversation and for some reason, the reply is getting turned off. Can I have an explanation?

    Andrew

    • The WordPress software will only do so many levels of nesting. Just go up one level and continue on that same level. But I think that there is a good reason to stop when the max is reached.

  41. Judith Curry

    Here are my comments:

    The summary by Dr. Wolff (reported on Bishop Hill) of the points of agreement at the Cambridge Workshop is a good piece of work.
    Points 1 through 5 seem to have had almost universal agreement:
    1. CO2 is a GHG
    2. GHE from H2O and CO2 occurs in real life
    3. GHE does not saturate with more CO2 (some reservations expressed)
    4. CO2 concentration has risen over past 200 years
    5. human CO2 emissions have played a major role in this increase

    Point 6 suggested that “we must expect at least some warming”

    As you stated, this is an incomplete argument. IMO one should add the phrase “all other things being equal”

    Point 7 adds that everyone agrees “that the climate has warmed over the last 50 years, for whatever reason”

    Montford adds the question whether or not the warming of the past 50 years is “statistically significant” (Doug Keenan, WSJ)

    You point out that the magnitude of this warmth also appears to be a point of debate.

    Montford also raises the question concerning the “lack of warming” since 1998. Your April-July analogy would point to the assumption that this is a “cooling blip” in a warming trend, but only time will tell if it is really the start of a multi-decadal cooling trend, instead.

    Point 8 concerning the role of solar variability in the observed changes appears a bit more contentious, as you point out. New studies have indicated a stronger direct solar role, but the results of the CLOUD experiment at CERN may shed some new light on indirect solar influence via clouds, which Roy Spencer has also recently addressed.

    Point 9 concerns the rate of sea level rise. Here there was no agreement with the IPCC premise that sea level rise has accelerated since 1993. Since IPCC’s claim was based on a change of measurement scope and methodology in 1993, it is hard to tell whether or not this is the primary reason for the apparent acceleration after 1993. One study using both tide gauge and satellite data (Wunsch 2006) showed a rate of rise half of that shown by IPCC for 1993-2003. Nils Axel-Mörner stated that there had been no real rise in sea level lately (despite the satellite readings). Latest studies using both satellite and tide gauge data (Cazenave 2009) have shown that the rate of sea level rise has decreased sharply starting in 2005 (from 3.3 to 1.3 mm/year), which is now at a lower level than the average over the 20th century (1.7 mm/year). Montford has also raised doubts as to whether the record shows any unusual trend directly related to AGW. The theoretical suggestion was made that warmer temperature should lead to thermal expansion and higher sea level. However, since both the atmosphere and the surface ocean appear to have stopped warming recently (ARGO, HadCRUT), it is hard to tell whether or not sea level trends will be much different from the historical record.

    Your point that sea level is fundamentally an item of local rather than global concern makes sense to me. At any rate the “doomsday” predictions of two-meter rise in this century or even this decade (as made by Ban Ki-Moon in his “At the Tipping Point” op-ed in the International Herald Tribune, 17 November 2007) are nonsense and were apparently not discussed.

    Point 10 is where there was apparently no agreement. This involved the sign and magnitude of overall net feedbacks. Dr. Wolff apparently felt that there was enough certainty in the models to postulate a 2xCO2 CS of 2.0°C to 4.5°C, but this did not find general agreement among the group.

    Of course, this is the “alpha and omega” of the entire AGW premise.

    Montford points out that the models are unable today to make any meaningful estimates or predictions, but that he has concluded that a net overall positive feedback (as postulated by IPCC) is unlikely since “Earth’s temperature doesn’t seem to have got out of control in the past”.

    You state:

    I don’t buy the IPCC’s likely/very likely ranges for climate sensitivity

    On an earlier thread you have expressed this uncertainty concerning the model simulations (more cautiously than Montford).

    Insufficiently large initial condition ensembles combined with model parameter and structural uncertainty preclude forming a pdf from climate model simulations that has much meaning in terms of establish a mean value or confidence intervals [for climate sensitivity].

    .

    In another earlier thread you also expressed doubts regarding the “no feedback” climate sensitivity of around 1°C:

    there is too much that is not clear on this subject, and translating 3.7 W/m2 into 1C temperature increase seems incorrect to me

    The differences of opinion here between the scientists make all the difference as to whether AGW is a minor factor, which will not impact our climate greatly, or a potential major threat. If the upper end of the IPCC range with estimated feedbacks is right, we are in trouble. At the lower end, the problem will most likely not be serious. If Lindzen (or Spencer) are right and it is well below 1°C, there is no real problem to be anticipated (possibly even a net benefit).

    So it is clear why this one point remains the major point of disagreement, with the role of clouds the largest source of uncertainty.

    But, despite this basic disagreement on the most important point, it appears that the summary by Dr. Wolff has shown some areas of mutual agreement between those who support and those who reject the IPCC position on AGW so (while it was simply an unofficial set of personal notes) it has presented a breakthrough in the mutual understanding of several key points.

    Your summary says it all:

    The bottom line is that there are a few basics that everyone agrees upon, and plenty of topics where there is legitimate disagreement (which signals significant ignorance about the topic).

    Thanks for creating this thread. It should generate some good comments.

    Max.

    • manacker 5/25/11, 2:04 pm, Agree on

      Your point #3, GHE does not saturate with more CO2 (some reservations expressed) is equivalent to saying the Beer-Lambert Law does not apply in climatology. This is a first magnitude result for the AGW group. The fact that radiative transfer theory does not show saturation is not determinative, but instead raises questions about that troubled theory and its flaky application. It is not sufficient to overturn a law of physics.

      Your point #5, human CO2 emissions have played a major role in this increase is false, contradicted by the fluxes attributed to man and nature, and by the physics of the conservation of mass and dissolution. It is equivalent to saying that Henry’s Law coefficients are different for ACO2 and nCO2. That would be a first magnitude result for AGW but for the fact that it is an impossibility under AGW assumptions, namely that ACO2 and nCO2 are only different mixes of 12CO2:13CO2:14CO2 and that they mix in the atmosphere. No solution exists to solubility coefficients for these three species that results in IPCC claim that the observed increase in CO2 is due to ACO2. This problem would also be missing a mass balance analysis but for the fact of its impossibility. Tangential problem include that IPCC’s key fingerprints of human activity, namely O2 decrease tracking CO2 increase, and δ13C lightening tracking CO2 emissions, are manufactured by graphjunk. A second problem is that IPCC’s conjecture about the role of CO2 emissions requires the surface layer to be in thermodynamic equilibrium, leading to its irrational rehabilitation of the failed Revelle buffer factor.

      Your observation about solar variability omits the results of Stott et al. (2003) showing that a previously unknown amplification factor exists in the atmosphere. This was pre-AR4, and was dismissed by IPCC for other reasons. It was reconfirmed by Tung, et al. (2008), pre-AR5. The connection to clouds is the only known explanation for the amplification.

      Your acceptance of the lament about uncertainty in the sign and magnitude of overall net feedbacks is the acceptance of IPCC’s model that cloud feedback does not include cloud cover. Among all of IPCC’s errors, this failure to model cloud albedo rises to the top when we treat the climate problem as the simple binary decision, H0: AGW does not exist, H1:AGW exists.

      • Jeff Glassman

        Thanks for your post.

        I was not expressing my own personal conclusions on the various points noted by Dr. Wolff, but rather his notes regarding the conclusions of the group of scientists that were present at Cambridge, along with Andrew Montford’s comments.

        There is no question that Wolff is a “believer” in the premise that AGW has been a major cause of past warming and, thus, represents a potential serious threat, as the tenor of his questions show (particularly the one related to 2xCO2 climate sensitivity, to which he got no agreement).

        I would personally agree with his 1, 2 and 4.

        On point 3, I would ask whether or not the Beer-Lambert Law means that the logarithmic relationship between CO2 and temperature ends at some point beyond which added CO2 no longer has any impact whatsoever or whether the relationship continues to become smaller logarithmically. This seems to be a point of disagreement.

        On point 5 I would agree that “human CO2 emissions have played a role”, but am skeptical that this was “major” until I can see some empirical data validating this premise.

        On point 6 I would agree “we must expect some warming” with the add-on “all other things being equal” (which, of course, is most unlikely).

        On clouds I personally believe Spencer is right in stating that these exert a separate forcing (rather than simply a feedback to GH forcing as assumed by the models cited by IPCC). Other studies (Palle) seem to point in this direction.

        On solar forcing I have not come to any particular conclusion.

        There have been many credible solar studies suggesting that around half of the observed 20th century warming can be attributed to the unusually high level of solar activity (highest in several thousand years) with most of this occurring in the first half of the century. These would obviously mean that there is something beside just measurable direct solar irradiance at work (as assumed by IPCC).

        A link between solar activity and clouds (either Svensmark or via PDO/ENSO/etc. or something else) is plausible. The CERN results may tell us more.

        On uncertainty in the sign and magnitude of feedbacks, I simply reacted to Wolff’s statement that there was enough certainty in the models to postulate a 2xCO2 CS of 2.0°C to 4.5°C (to which he did not get general agreement). Spencer/Lindzen have estimated this to be well below 1°C, based on satellite observations rather than simply model simulations, so I would be rationally skeptical of Wolff’s statement.

        So much for my personal thoughts, for what they are worth.

        Max

      • manacker 5/26/11, 8:39 pm, Agree on

        Thanks for the clarification and attribution to Wolff on those points.

        The logarithmic relationship has no à priori model, that is a cause and effect of its own. It is a piece-wise approximation to radiative transfer, and a best fit to the middle of the Beer-Lambert Law. That Law produces a classic dose-response relationship between RF and the concentration in our application of CO2. Google for “dose response curve” and you’ll see a vast number of them. E.g.,

        http://www.softchalk.com/lessonchallenge09/lesson/Pharmacology/Introduction_088.html

        Imagine that the curves there represent two stages of the same dose (in log [CO2]). Each curve on the left is horizontal, representing the background effect, and horizontal on the right, representing the saturation effect, at least of the particular stage. In the middle the curve is approximately a straight line, or logarithmic. Now imagine that the second response is added to the first, so that the saturation level for stage 1 is the background effect for stage 2. Now imagine two more stages added to the right and accumulated upward. Those four stages are a best fit to the MODTRAN result from 0 to 100% CO2 in the atmosphere. The MODTRAN result is a continuous, three piece logarithmic fit, convex up, which is easily accommodated using the four dose-response curves.

        Stages 1 and 2 in the MODTRAN fit seem to fit the atmosphere to the extent of the resolution of the CO2 absorption spectra. Stages 3 and 4 are way down in the continuum of absorption, and have yet to be validated. These areas are the skirts of absorption lines, and the shape of those skirts is most uncertain. The MODTRAN model seems ultimately to have no windows of zero absorption anywhere, but that could be a conjecture, an assumption designed to make CO2 absorption appear logarithmic throughout its entire range. However, up to a doubling of current CO2 levels, the first two stages and the log assumption would be good enough. That is, from the standpoint of climate, we apparently need not worry about the saturation of CO2 absorption. There are other reasons not to worry about it. For example, the RT results are not too good:

        The RF from CO2 and that from the other LLGHGs have a high level of scientific understanding. Note that the uncertainty in RF is almost entirely due to radiative transfer assumptions and not mixing ratio estimates, therefore trends in RF can be more accurately determined than the absolute RF. Citation deleted, AR4, ¶2.3.1, p. 140.

        Radiative transfer theory is sound and precise, but its instantaneous accuracy depends on how well the atmosphere is modeled, and its average accuracy is meaningless. David Archer’s MODTRAN version uses a standard atmosphere with CO2 concentration proportional to pressure. When did anyone ever witness the real atmospheric lapse rates being precisely equal to the standard? And we know from the lifetime formula and from recent satellite imagery that CO2, contrary to IPCC’s critical assumption, is not well mixed. It is not an LLGHG, where long means long enough to be so well mixed that the regional MLO data can be assumed to be global data and all the CO2 measuring stations can be calibrated to agree with MLO.

        The next problem is that RT is not linear. As a result the average response of the RT algorithm is not equal to the RT algorithm response to the average atmosphere. This holds on every time scale, instantaneous, diurnal, secular, or finally climate. Furthermore, the RF from RT theory is not unique. An infinity of lapse rates can produce the same total RF, so the analysis cannot converge. It can be fine-tuned by playing around with different atmospheres until you get your preconceived result, but that is not science. To the extent that that is done, it is a subjective bootstrap to produce desired results and it has no predictive power.

        Finally, CO2 does not accumulate in the atmosphere, especially not ACO2 without nCO2 as IPCC assumes, so the hypothesis that ACO2 causes global warming can be rejected. Let the physicists perfect RT and explore the depths of the continuum to their hearts content. It has no relevance to climate except for government funding.

        P.S. The idea that a climate sensitivity can be specified is identically the assumption that the response is logarithmic. That poses no particular problem in a narrow band of concentration. The problem with IPCC’s climate sensitivity lies elsewhere. IPCC estimates it open loop with respect to cloud cover, meaning that it is open loop with respect to real cloud albedo and not the specific cloud albedo as IPCC defines it. As you pointed out at 2:16 pm, real world climate sensitivity is running around 0.6. That is one fifth of IPCC’s nominal 3ºC. That is best attributed to closing the cloud clover loop.

      • Jeff,
        I agree with many of your statements, but there are points, which I see differently

        The logarithmic law is not a fit to a part of the Beer-Lambert exponential, but it’s a fit a sum of very many Beer-Lambert exponentials. The relative weights of these exponentials are such that the sum behaves nearly as logarithm over a wide range of concentrations. It’s far from logarithmic at both extremes (low enough to be far from saturation even at the center of the 15 um peak, or high enough to saturate over the whole gap left by H2O). These extremes are, however, so far that they are of no practical relevance for the Earth climate.

        IPCC doesn’t assume that ACO2 will specifically accumulate in the atmosphere. Rather it claims that the total amount of CO2 in the atmosphere will be affected for a long time by the ACO2 emissions allowing it, however, to mix with nCO2 in all CO2 storages that are connected to the atmosphere. Mixing with some of the other storages takes very little time (often less than a year), while mixing with other storages is very low. Mixing with deep oceans takes hundreds or thousands of years and geologic processes even longer.

      • Pekka Pirilä, 5/27/11, 9:27 Am, Agree on

        By The logarithmic law is not a fit to a part of the Beer-Lambert exponential, I assume you mean not exponential but the Beer-Lambert S-curve, as graphed against the log (C/C0). Either that or by exponential you mean the form a – b*exp(-kC). But then I don’t see how you can deny that a straight line fits the middle of that S curve to an arbitrarily small accuracy.

        I believe that when you talk about very many Beer-Lambert “exponentials” you are considering the Beer-Lambert Law to be valid only for monochrome light. That is a popular misconception. Being monochrome is sufficient, but not necessary. The Beer-Lambert Law applies an empirical coefficient. Precisely speaking, it applies to a complex spectrum of light for which all the spectral components have the same empirical coefficient, and not restricted just to the same frequency. I don’t know that anyone has worked out those empirical coefficients or decided just how close they have to be to one another for the Beer-Lambert Law to be a good approximation. I do know that for the Archer MODTRAN algorithm, only four Beer-Lambert curves are necessary to fit the RT response as well as three logarithmic pieces for the full CO2 absorption spectrum and the full range of 0 to 100% CO2. So, I could agree with you if by “very many” you mean four or less.

        I disagree with your conclusion that IPCC doesn’t assume that ACO2 will specifically accumulate in the atmosphere. That is precisely what it does. It uses equilibrium chemistry to develop the Revelle buffer factor, and that factor in either of two formulations (Revelle & Suess or Zeebe & Wolf-Gladrow) is expressly a ratio for which the numerator is the relative concentration of ACO2 in the atmosphere. The Revelle factor is not defined for nCO2, and IPCC never uses it for nCO2. IPCC only gives ACO2 the bottleneck treatment.

        IPCC assumes that nCO2 is in yearly balance while ACO2 is bottlenecked in the atmosphere. It (1) determines a climate response to nCO2, (2) calculates a climate response to ACO2, and (3) adds the two to say that the sum is the total climate response. At the same time, IPCC declares that the climate is nonlinear. It says incorrectly, highly nonlinear, which has no meaning; nonlinear is a state, not a measure. It also means not that the real climate is nonlinear, because that has no meaning either, but that its model of climate is nonlinear. But if its GCM is nonlinear, than the response of the GCM to the sum of nCO2 + ACO2 is not equal to the response to nCO2 plus the response to ACO2. This is not just a matter of a little inaccuracy. No theory tells what the combined effects are without specifying the actual nonlinear relationship.

        Natural and anthropogenic CO2 are hopelessly mixed in the atmosphere and lose all meaning as soon as they are mixed. Atmospheric CO2 is a new mixture of 12CO2:13CO2:14CO2, and is absorbed in surface waters according to the individual Henry’s Law coefficients for each isotopic species.

        IPCC has the attribution of atmospheric CO2 quite wrong.

      • Jeff,
        It’s totally clear that the Beer-Lambert law is valid, if the absorption strength of the material is the same for all radiation considered. We know, however, that this is almost never true for other than monochromatic light.

        I’m sure that many people have worked true, what is required to have a good agreement with logarithmic dependence over a reasonable range. It requires actually that the shares of different absortivities must have on exponential frequency distribution. Looking at curves, which show the various absorptivity peaks of the side of the 15 um peak, we notice that it’s indeed approximately exponential. That’s the reason for the validity of the logarithmic law for CO2.

        Concerning the CO2 concentrations, many parts of the analysis refer to deviation from equilibrium. They use models that calculate the equilibrium assuming that the concentration changes as a combined effect of anthropogenic influence and natural responses to the deviation. Some of the models do this explicitly, some others are using simpler multi-exponential parameterizations based on such explicit models.

        The nonlinearity of various responses becomes significant when deviations from a base situation grow. Thus for example the above mentioned multi-exponential parameterizations are valid only over a limited concentration range, as they are linear in the addition of CO2. All this has well known for long and taken into account in the IPCC work. (Some papers may fail to take all known facts properly into account.)

      • Pekka Pirilä, 5/27/11, 11:16 am, Agree on

        Here is a declaration of faith to share.

        • Put no faith in experts qua experts, but only in their fully cited, accurately quoted and publicly and freely accessible claims. (Counter example: someone, somewhere showed the limitations of the Beer-Lambert Law.).

        • Doubt any expert who professes an affirmative belief system. (E.g., especially and in particular, that AGW exists.)

        • Ignore experts who have a problem with the definition of words. (E.g., equilibrium, dynamic equilibrium, thermodynamic equilibrium, and balance are interchangeable.)

        • Doubt every claim in any paper published in one-sided professional journals or in any paper that is not freely available to the public.

        • Trust the IPCC that it has laid out the best story possible in its Assessment Reports in support of its preconceived notions that AGW exists, and that it is leading to an inevitable global catastrophe. Conversely, trust that what IPCC omits is harmful to its assumption that AGW exists and its claim of impending disaster.

        • Trust that the IPCC’s targeted audience, the “Policymakers” of Western Governments, do not read scientific papers but get their notions about AGW and CO2 from IPCC and its supporters.

        Climatology draws from the fields of mathematics and statistics, physics, and system science. For those not familiar with system science, it is the engineering field covering, among other things, modeling, especially large scale modeling, plus detection, estimation and prediction theories, and essential concepts like feedback, signals in noise, stability, linearity, orthogonal representations, correlation, and solutions of equations. Consequently, reserve special trust beyond peer review for review from the higher authorities of mathematicians, statisticians, physicists, and system scientists of climate modeling relevant to their specialties.

  42. Schrodinger's Cat

    I think your summary is a good one. There is legitimate disagreement due to many areas of ignorance. It reminds me of the old management advice : If you can’t make a clear decision it means that you don’t have all the required information.
    In many respects the climate story displays a gross distortion of these simple truths. Many far reaching decisions have already been made. These have clearly been based on a mixture of ‘agreed’ knowledge and ignorance. The ignorance has manifested itself as assumptions in climate models. In effect, the ignorance has been claimed to be settled science. Some of the practices exposed by Climategate demonstrated the determination to discourage any funding or disclosure of science that may reduce the ignorance but undermine the established assumptions. So now huge decisions and lots of governmental, political, socio-economic, environmental, and energy issues ride on this. In addition there are lots of activist groups pushing their own agendas. All based on a mixture of truth and potential lies. Ignorance replaced by an assumption and sold as a truth may well be a lie.
    There has been a tendency for a few scientists and politicians to describe the ignorance as ‘uncertainties’. In my view this is not just a euphenism, it is misleading. Ignorance, if we are to be honest, means that we just don’t know.

    Now, agreed ignorance would be very valuable common ground. It would be a good start. It might even bring honesty, integrity and science back into fashion.

  43. WisconsinitesForGlobalWarming

    I am very interested to hear Dr. Curry’s and other pro-AGWers’ thoughts on David Wojick’s excellent list of items we agree on (posted above on May 25, 2011 at 7:04 am):

    S1. Climate changes naturally.
    S2. The mechanisms of natural climate change are not well understood.
    S3. The climate system includes many non-linear feedbacks.
    S4. These feedbacks are capable of producing counter intuitive behavior, surprises and unforced oscillations.
    S5. The climate is chaotic.
    S6. Chaotic behavior is intrinsically unpredictable.
    S7. We have no direct measurements of the major climate parameters over long periods of time.
    S8. The indirect measurements of climate parameters that we have are of unknown accuracy.

    • I like your first list better. While it was equally stupid, it invoked fewer concepts you do not understand, and it was much shorter. :)

  44. Wolff wrote a good comment at Bishop Hill, which I also highlight at my blog: http://ourchangingclimate.wordpress.com/2011/05/25/eric-wolff-areas-of-agreement-public-debate-about-climate-science/

    What particularly struck me was this passage on expertise:

    “I freely admit that I am not an expert on all, or even most, aspects of climate. When I reach a topic that I have not previously studied, I go to those who are experts, either in person or by reading their work. I maintain scepticism about some of their conclusions, but my working assumption is that they are intelligent and that they have probably thought of most of the issues that I will come up with. Can I observe as an outsider to the blogosphere, that it surprises me that so many people, presumably mostly with even less knowledge and training than me, seem absolutely convinced they have mastered every area of climate science.”

    • WisconsinitesForGlobalWarming

      Bart, I see the passage from Wolff as some what *typical* of the more general debate on Climate Science insofar as it appears, to me, more of a comment aimed at distraction than at addressing the topic. So much of the *debate* on climate as I read it seems to be eerily similar to watching a very fine magician… there is a lot of misdirection going on to convince you that what you are seeing is real, yet I know, as a scientist and an engineer, it isn’t.

      It seems to odd to me that the *lists of what we agree on* that I have seen are being promoted by *warmers or luke-warmers*. My experience has always been that individual pushing for agreement tends not to be the one negotiating from a position of strength.

      • “yet I know, as a scientist and an engineer, it isn’t”

        Guess those who would most benefit from understanding and taking to heart a certain point go through the greatest lengths not to.

      • WisconsinitesForGlobalWarming

        So you believe in magic Bart? That explains a lot. :)

    • The quote from Dr. Wolff is exactly how we got into this mess. “[the] working assumption is that they are intelligent and that they have probably thought of most of the issues that I will come up with.” Agreed. But then we found out that they were using questionable statistical methods, the HSI. Then we found out that they were gaming the system, the leaked emails. Then we found out that they unscrupulously hid and discarded inconvenient data, hide the decline.

      With all of this now out in the open, Dr. Wolff seems quite disingenuous with his criticism of “so many people, presumably mostly with even less knowledge and training than me,” statement. Basically we are back at square one. We must implicitly trust the climate scientists since we couldn’t possibly understand all of the intricacies and depth of their work? How can anyone take that position after climategate, the HIS, McIntyre and McKitrick and all of the others? Phony self-righteous indignation if you ask me, let’s see the data, make it openly available if you are so sure!

      • David Bailey

        This is what gets me about this concept. I mean, I don’t see how the debate can progress without some admission of what has happened, and some exploration of just how far the rot went.

      • WisconsinitesForGlobalWarming

        Thanks RB, exactly my point which Bart missed and then replied with his attack post… ugh.

      • Nebuchadnezzar

        Phony self-righteous indignation if you ask me, let’s see the data, make it openly available if you are so sure!

        There’s a nice list of openly available data sets here:

        http://www.realclimate.org/index.php/data-sources/

        Some of these have been available for years.

    • Wolffe seems absolutely convinced he knows how to make assumptions.

      Science is the belief in the ignorance of experts.
      Richard Feynman

      and non-experts!

    • Bart

      The passage you cite is a clear “argument from authority” and hence a logical fallacy.

      Max

      • Going to a physician rather than to an English teacher when you’re sick is not a logical fallacy; it is logical.

      • andrew adams

        Personally I prefer to find someone on the internet who will tell me I’ve got nothing to worry about and take his word for it.

      • andrew adams

        But on a more serious note, speaking as a layman if I don’t go to experts when I want to learn about a subject (any subject, not neccessarily climate change) who do I go to?

      • andrew adams

        You ask:

        speaking as a layman if I don’t go to experts when I want to learn about a subject (any subject, not neccessarily climate change) who do I go to?

        If you are a “rational skeptic” in the scientific sense – see Wiki:

        http://en.wikipedia.org/wiki/Scientific_skepticism

        rational skepticism (also spelled scepticism), sometimes referred to as skeptical inquiry, is a practical, epistemological position in which one questions the veracity of claims lacking empirical evidence or reproducibility.

        you will seek out all the studies available, looking for “empirical evidence”.

        According to the scientific method, this could be from actual physical observations or reproducible experimentation. Model studies based on theoretical deliberations, such as those cited by IPCC to derive 2xCO2 climate sensitivity, do not constitute “empirical evidence”, however. The data must be based on actual real-life data.

        So I would download the temperature records (HadCRUT, UAH, etc.) the data on atmospheric CO2 concentration (Mauna Loa) and human CO2 emissions (USEIA). I would check out papers regarding the accuracy or possible spurious signals in these records, to make sure these are sound.

        Then I would try to get opinions of different scientists: both those supporting the IPCC premise that AGW has been the primary cause of 20th century warming and thus represents a potential serious threat, and those who do not support this premise (there are plenty on both sides, a the “science is NOT settled”).

        How robust is the statistical correlation between atmospheric CO2 and global temperature anomaly (without a robust statistical correlation, the case for causation is weak or non-existent)?

        Are there other possible cause for the warming and how well do these correlate statistically?

        Check out the arguments of both sides as well as the empirical evidence presented.

        My formula (not scientific): one piece of data based on real-time observations is equal to 100 interpretations of reconstructed paleoclimate data and equal to 10,000 model simulations based on theoretical deliberations.

        Unfortunately, almost all of the IPCC projections are based on model simulations base on theoretical deliberations, with a bit of paleoclimate interpretations thrown in, but almost no actual physical evidence.

        Don’t take any one person’s (or group’s) word for it. Especially not if there is even a slight suspicion that there may be a “hidden agenda” behind that individual’s (or group’s) story.

        Look for exaggerations or distortions of the data, as have recently been exposed by climategate, etc.

        Check out all the available data and then make up your own mind.

        Above all, when new data are presented, consider it (and change your mind, if the new data warrant this).

        This may not work for everyone, but that’s my approach.

        Max

      • Bart Verheggen

        But going to a “snake oil salesman” who has a hidden agenda is a logical idiocy.

        Forget that old “physician” saw, Bart. It does not apply here.

        An “argument from authority” is a “logical fallacy”.

        An “argument from evidence” is what is required instead.

        Max

      • And what do you do when someone doesn’t want to hear or doesn’t like the evidence?

        Then I guess you do what Andres Adams wrote @5:19

        It’s all so logical

      • Bart Verheggen

        You have asked a question:

        what do you do when someone doesn’t want to hear or doesn’t like the evidence?

        – If he/she “doesn’t want to hear” you ignore him/her (what else can you do?)

        – If he/she “doesn’t like the evidence” this can either be a) because he/she cannot understand the way you presented the evidence or b) because the evidence, itself, is not robust.

        So you should check to see how robust the evidence you presented really was and how well you explained that evidence.

        Seems pretty straightforward to me, Bart.

        Max

      • barn E. rubble

        RE: “Going to a physician rather than to an English teacher when you’re sick is not a logical fallacy; it is logical.”

        And if said physician was paid only if something serious was found I suppose, logically, something serious would be found.

        Perhaps ‘adjusting’ &/or ‘interpreting’ the thermometer readings until the sought after fever has been reached?

        -barn

  45. Schrodinger's Cat

    I would like to recommend the concept of ‘agreed ignorance’ as a tool for finding common ground. Psychologically, it does not create the same charged positioning that leads to the polarization that we see when each side takes up battle lines on the basis of belief – sorry, I should have said ‘alleged settled science’.
    The ignorance defines the areas untainted by false consensus, the subjects that may prove pivotal in our future understanding. Honest scientists should be eager to agree areas of ignorance on the understanding that normal ‘acceptable’ science will be utilised to shed light on the truth.

    It is always useful to identify and debate that which is agreed, but in this case it may be more fruitful to identify and agree to investigate that which is not agreed, but which is our common ignorance. I suspect the difficulty will lie in persuading the fanatical on both sides to equate some established beliefs with “we really don’t know”.

    Agreeing that we don’t really know something is a leveller. It is also seen as a sign of honesty because it does not indicate subsequent bias of direction.

    I do believe that it is the best way to re-define where we are on climate science. This should really be embraced by scientists – look, more research is needed ….

    • I agree, but unfortunately the basic argument is on what we don’t know. My list of basic skeptical points is mostly about ignorance, and AGW proponents deny this ignorance.

    • “I would like to recommend the concept of ‘agreed ignorance’ as a tool for finding common ground.”

      Unfortunately, the ignorance is not equally shared among climate scientists and “skeptics.”

      Unfortunately, many “skeptics” seem prone to generalize from their own ignorance and project it outward onto scientists. “Magnets — you can’t explain that” reasoning.

      • Climate “Scientists” love to make alarming predictions that don’t come true … and no one should ever take them seriously. They are just trolling for grant money.

      • What it so often comes down to: hatred and fear of science, rejection of science as a con or a scam.

        Sad. Transparent and sad.

      • Its not science people are afraid of, it is corrupt “scientists”. All professions have a duty to weed out corruption.

        But Climate Gate showed us that corrupt “scientists” conspired to keep papers out of journals that would have cut off the flow of money to the corrupt hockey team.

        Your defense of corruption is the problem.

      • So would you say your paranoia about science and hatred of scientists has been fed by this event you call “Climate Gate”? You don’t realize that this belief in a “Climate Gate” is a delusion?

      • You are projecting Robert. Consensus has hatred and fear of science.

        Sceptics love science.

      • Which is one way to recognize the difference between real skeptics, and science-hating climate “skeptics” who, although they call themselves “skeptics,” are in reality fanatical and unquestioning in their beliefs.

      • I said STOP projecting!

  46. Jim D

    You forgot to consider that it is not the “added CO2″ that counts, but the ln of the total CO2 concentration at that time.

    1940: 307 ppmv (IPCC estimate from ice core data)
    2000: 369 ppmv (Mauna Loa)

    ln 307 = 5.727
    ln 369 = 5.911

    d(ln) = 5.911 – 5.727 = 0.184

    2xCO2
    ln2 = 0.693

    dT (1940-2000) = 0.4

    dT (2xCO2) = 0.4 * 0.693 / 0.184 = 1.5C (if ALL 1940-2000 warming assumed to be due to CO2)

    Alternate case:
    50% of 1940-2000 warming assumed to be due to CO2

    dT(2xCO2) = 0.2 * 0.693 / 0.184 = 0.75C

    Since we do not know what % of observed warming was due to CO2, we do not know what the 2xCO2 sensitivity really is.

    Max

    • Using your numbers
      ln 280 = 5.634 (pre-ind)
      ln 307 = 5.727 (1940)
      ln 369 = 5.911 (2000)

      The warming from pre-industrial to 1940 is proportional to the difference 0.093, and from 1940-2000 the difference is 0.184, so the average warming rate should be double from 1940-2000 compared to all the warming up to 1940, and it still accelerates towards the end.

      • Jim D

        The global warming from 1910 to around 1940 was indistinguishable from that from 1970 to 2000, even though the CO2 increase was much less.

        This is the point Girma has made graphically.

        In addition, there has been no acceleration towards the end (despite IPCC claims).

        Simply plot the first 40 years of IPCC’s revised 20th century (1906-1945) on woodfortrees with the linear rate.

        Then plot the whole century (1906-2005) with linear rate.

        You will see that the first 40 years had almost twice the warming rate as the whole century.

        This is the kind of analysis that IPCC makes in its AR4 (Ch.3) and SPM reports (in reverse) to show acceleration of warming by comparing short with longer time periods.

        Obviously “smoke and mirrors” (just like my example).

        Max

      • The first rise up to 1910 is much faster than expected for CO2 alone, but can be accounted for if you add 0.2 C for a solar effect as sunspots were doubling in that period. Removing this solar effect, the CO2 effect is accelerating in accord with about 3 degrees per doubling, allowing for the dimming effect of rising aerosols especially prior to 1980. It is not just CO2, and nobody says it is. The thing about CO2 is it only gets more important with time, while these other effects don’t.

      • Jim D

        the CO2 effect is accelerating in accord with about 3 degrees per doubling, allowing for the dimming effect of rising aerosols

        The “dimming effect of rising aerosols”?

        That’s a red herring, Jim.

        The physically observed data,without that “red herring” or the other one (Hansen’s “hidden in the pipeline” postulation) show a 2xCO2 CS of around 1 to 1.5C (not 3C).

        If we include some natural forcing impact (solar, etc.) we arrive at even less for CO2.

        Don’t delude yourself with silly rationalizations or excuses, Jim.

        Max

  47. 1. Everyone in the room agrees that CO2 does absorb infrared radiation, as observed in the lab

    I might qualify that. Every agrees gases (and materials) have specific IR absorption spectra.

    I am still looking to try to find lab data on the quantum of IR (probably laser) absorbed/scattered/backscattered/transmitted and measured temperature changes caused by CO2 in various concentrations in the lab with a theoretical prediction or justification of that.

    I would like to see the quantum of measured change in thermal gradient in the CO2 column with a vertical IR laser.

  48. Tom Scharf

    I agree.

    We agree on most everything except the only thing that really matters:

    *** Where is the climate going? ***

    Just a small issue. Still waiting for the results of a survey on what climate scientists think about the reliability of the current crop of climate models. A few sample questions:

    1. Do you believe the public should trust the predictions (projections, scenarios, et. al.) of climate models?

    2. Do you believe that competing ideas on climate modeling (decadal oscillation, etc.) has been adequately represented? (i.e. is the focus on CO2 holding back the science)

    3. How would you rate the performance of the climate models over the last 20 years (poor, fair, good, excellent, not enough info)

    4. Do you believe past back casting skill is a good predictor of future prediction skill in climate models?

    I admit there is a bit of “don’t ask questions you don’t already know the answer to” in this list, and I could add many more examples of the failures of expert prediction (a true oxymoron) to this area of the science.

    There seems to be a bit of word play going on here that if we can agree on the basics, then we must agree we understand the problem. Progress has been made on explaining what caused past events (El Nino, etc.), but the translation of that to ability to make accurate future predictions is an epic leap that is not justified.

    Climate science painted itself into a corner. They exaggerated their ability to predict the future, and lost credibility when expectations were not met. Now they must perform in order to regain credibility. It will take decades. I eagerly await the (lack of) introspection in AR5 on the skill of previous climate models.

    • v good questions

    • Tom, I’m curious: do you blame biologists for the fact that 60% of Americans don’t believe in evolution?

      Do you feel physicians’ lack of credibility is the reason people believe vaccines cause autism?

      Do you think poor behavior by geologists is responsible for people believing the earth is 6,000 years old?

      I’m not sure you can assume that because a certain group of people reject what science is telling them, that science or scientists have failed. I don’t see any evidence that science has failed, let alone that scientific failure are driving “skepticism.”

      We should hold people responsible for their own irrational beliefs.

      • Bad Andrew

        “Tom, I’m curious: do you blame biologists for the fact that 60% of Americans don’t believe in evolution?”

        Robert,

        60% of the population probably aren’t propagandized drones, like you are Robert.

        Andrew

      • So evolution is propaganda, eh?

        Ladies and gentlemen: I present to you a climate skeptic.

        Better science is not going to cure people who are anti-science and anti-reason.

      • Better science is not going to cure people who are anti-science and anti-reason.

        Nor will it cure your brand of ignorance.

      • The ignorance that causes me to believe in the theory of evolution? I’ll muddle through somehow.

      • No – the ignorance that causes you to believe that those who disagree with you are ignorant.

      • So you are accusing me of being ignorant because I supposedly accuse people I disagree with of being ignorant — like you just did. Which would make you ignorant . . . which might suggest that those that call you ignorant are right.

        It’s very meta. Perhaps David, our resident philosophy major, can sort it out.

        Again, you are talking about people who deny Darwin’s theory of evolution.

        If you want to defend that as a reasonable point of view, feel free. That tells us something about your level of reasoning.

      • So you are accusing me of being ignorant because I supposedly accuse people I disagree with of being ignorant

        Yup.

        like you just did

        Nope. I said you are ignorant because you fail to understand that those who disagree with you may (and apparently usually do) know more about the subject than you do. And yet you call them ignorant. Has nothing to do with whether or not you disagree with me.

        you are talking about people who deny Darwin’s theory of evolution.

        No, I’m talking about you. Those who deny Darwin’s theory of evolution have their own problems. But they’re not as unresolvable as yours. Nor do they need me to defend them.

      • Bad Andrew

        Robert has trotted out the ol’ “I think evolution is true, therefore if you don’t believe in Global Waming you are insane” manuever.

        Clever, Robert.

        Andrew

      • Bad Andrew

        sorry, maneuver. :P

        Andrew

      • Robert,
        Appealing to evolution is the best choice for someone who cannot discuss the problems of climate science and the AGW social mania.

  49. “Do you feel physicians’ lack of credibility is the reason people believe vaccines cause autism?”

    Well, that peer reviewed paper in the Lancet promoting that idea did make people believe it.

    The Lancet only retracted it last year – after 13 years.

    http://briandeer.com/mmr/lancet-retraction.htm

    Pal review is quite common in climate “science”. And making stuff up.

    • “Pal review is quite common in climate “science”. And making stuff up.”

      No matter how many times you assert that, it’s won’t magically become true.

      Certainly you have a few frank liars out there — the Wegmans, the Wakefields. Which is why it is important to pay attention to the interlocking work of hundreds of scientists, not the fringe, whether it is the vaccines-cause-autism fringe or the AGW-skeptic fringe.

      But in both cases, the communities that believe fanatically in the pseudoscience preceded the rare event of their fantasies sneaking past peer review, and they continue to prosper even as their heroes fall. Their belief does not come from bad science and dishonesty: it is the wind beneath the liars’ wings.

      • Read the article bobby.

        What did Wegman lie about?

        “he interlocking work of hundreds of scientists”

        Don’t you mean the Hockey Team – 3 or 4 or 5 people connected by multi-million dollar grants?

        I hope Nature doesn’t take forever to retract all the lies like it has taken the Lancet to do.

      • Sorry, brucie, your widdle tantrum has reached a dead end.

        You are left sputtering that your lying friend that had his paper yanked really didn’t do anything wrong — just a little stealing other people’s work and lying about it, that’s not lying by “skeptic” standards, is it?

        Too bad for you: integrity doesn’t get graded on a curve.

        “I hope Nature doesn’t take forever to retract all the lies like it has taken the Lancet to do.”

        Fortunately you “skeptics” rarely fool the reviewers at Nature, so there aren’t many of your lies to retract, but thanks for your concern.

      • My buddy, a pediatrician, says the US scientific establishment never fell for Wakefield’s study. So the parallels here are flipped.

      • bobby, Plagiarism implies he borrowed accurate material.

        Are you saying the material he borrowed was lies?

        I’m not sputtering. In fact I thank you for coming out of the closet. People still defending the big lie “hockey stick” are mentally ill or profoundly dishonest.

        Lancet took 12 year to retract it lies. Nature will someday realize the damage it has done to “science” just to make a buck.

      • “Plagiarism implies he borrowed accurate material.”

        Complete and utter nonsense. Plagiarism is about not acknowledging sources. It has nothing to do with the veracity of what is claimed. It is entirely possible to plagiarise a lie.

      • …or falsehood or mistake.

      • But did he plagiarize a lie, or did he plagiarize a plagiarist or did he tell the inconvenient truth?

        “Lost in the recent controversy over Said et al 2008 is that the Climategate documents provided conclusive evidence of the hypothesis originally advanced in the Wegman Report about paleoclimate peer review – that members of the Mann “clique” had been “reviewing other members of the same clique”.”

        http://climateaudit.org/2011/05/23/climategate-documents-confirm-wegmans-hypothesis/

      • Robert,no matter how often you….deny it, it is still true that pal review and collusion is the hallmark of AGW promotion.

  50. Willis Eschenbach
    6. I then suggested that if we agree all these statements above, we must expect at least some warming.

    JC comment: as it stands, this is an incomplete argument.

    As it stands, this is a marvelous understatement.

    w.

    • Willis

      we must expect at least some warming

      Quick sanity check.

      “We” (at least a large percentage of “us”) live in the northern hemisphere.

      It is late May, so “we” still have summer ahead of use.

      So “expecting at least some warming” is a no-brainer.

      Max

  51. WHAT WILL BE THE EVIDENCE FOR NATURAL GLOBAL WARMING/COOLING?

    The overall global warming rate was about 0.06 deg C per decade.

    http://bit.ly/k9cWaz

    For the period 1970 to 2000, the global warming rate was 0.16 deg C per decade.

    http://bit.ly/jFmOny

    The global mean temperature data has an approximately cyclic component.

    http://bit.ly/iApyoc

    Therefore, during the global warming phase,

    Global warming rate = Overall warming rate + Cyclic warming rate

    0.16 = 0.06 + Cyclic warming rate

    Therefore, the cyclic warming rate = 0.16-0.06=0.10 deg C per decade.

    Assuming the cyclic cooling rate is the same as the cyclic warming rate, we have:

    Approximate global cooling rate = Overall warming rate – Cyclic cooling rate

    Approximate global cooling rate = 0.06-0.10=-0.04 deg C per decade.

    Here is evidence for this cooling rate for the period from 1940 to 1970

    http://bit.ly/epk88B

    If this cooling rate of about 0.04 deg C per decade is observed for the period 2000 to 2030, it will be evidence for the cause in change in global mean temperature to be natural, contradicting anthropogenic global warming.

  52. Relax!

    I haven’t read through most of the posts here and only the start of Judith’s previous referenced thread, but I take great umbrage with the belief that the complete science of radiative transfer is well-agreed to and especially (from the reference), “…radiative transfer models rank among the most robust components of climate model, in terms of having a rigorous theoretical foundation and extensive experimental validation….” This is true at the very basic levels and quite good, but under the covers robustness and accuracy break down. I don’t mean that it becomes wrong (I don’t know), but the plethora of approximations, assumptions, proxies, and fill-in-the-gap-with-our-best-SWAG that it gets into clearly detracts from “robust” and “rigorous.”

    There is no way to cover all of the problems here (nor am I capable of it), but here are some of the examples I have run into in my efforts to understand just this topic (climatology is not my field), only to be frustrated.

    The general basics are well understood and in agreement: a CO2 molecule absorbs IR energy that would otherwise escape and cool the earth at the surface ala Planck. This molecule then converts the absorbed energy to heat/temp via molecular collision or to a some degree re-radiating it back to earth. This fundamental process is well understand with fairly precise detail in most instances and basically the reason Earth is not an ice ball.

    But, even here there is a curious anomaly. If you ask climate scientists (or even physicists) whether the temperature rises the instant the radiation is absorbed into vibration energy, you’ll get a bunch that say Yes and a bunch that say No (at least from my limited experience). I think I know the correct answer but that’s not pertinent. What is pertinent is that the scientists don’t know for certain and do not agree at this very basic level of supposedly robust and rigorous science.

    [For fun, how many here say YES and how many say NO to the question: Does the temperature of a gas rise when one of its molecules absorbs IR into exciting its vibration level -- with no other changes?]

    The process of how the photon energy gets transferred as heat to another molecule, that molecule in turn transfers it to another, and it bounces around the atmosphere until this energy packet finds its way to the upper tropopause and beyond, then collides with another CO2 molecule that is not already excited putting it back into vibration which this time relaxes through emission, maybe back down but maybe outta here… is well understand at the conceptual level but the piecemeal precise specifics borders on the ‘and now a miracle happens’ explanation. Again, I’m not saying the science is wrong. I think it was put out there with some very learned conclusions and inferences by very smart people after a lot of thought and analysis. But robust and rigorous and known with unwavering accuracy it ain’t.

    Non-saturation is usually explained by the collisional broadening of the absorption profile that occurs with increased density. Yet this broadening depends on which profile (Lorentz, Voight, or something like or in between) is assumed, occurs at the bottom range of the intensity, and collisional broadening is not material different from the bandwidth separating rotational energies. It almost looks like rotational energy levels are every bit as much responsible for band spreading as collisional broadening. I have yet to see a satisfactory explanation for this distinction. Are the assumptions none-the-less scientifically reasonable? Yes, on the surface and to my limited scope. Is the accuracy of the assumptions rigorous and robust? Not as I can see.

    The basic GH theory uses Planck function (T4 etc.) to develop various absorptions and emissions in serial slabs of the atmosphere. Yet CO2 and other GHGs do not absorb nor emit (much??) in accordance with the Planck function. However, with the assumption of various limits and parameters, the Planck function can be what seems to be a very close approximate to the real absorption/emission factors of GHGs and satisfactory and seemingly accurate for modeling uses. (Modeling the Planck function is magnitudes easier than individual molecular absorption, energy levels, equipartition and emission.) Deemed to be close enough. But not rigorous and robust and not 100% accurate. Actually it’s initially reasonably deemed to be close enough but as time goes on the assumption gets forgotten and becomes a iconic rule as it is today. How many climate scientists and physicists will in the same breath say the greenhouse warming theory is based on Planck’s function but GHGs do not emit or absorb according to Planck (ala greybody)? A dichotomy that most will affirm.

    The marginal CO2 Forcing and in turn the Sensitivity for increasing CO2 concentrations from today has never been experienced and only assumed based on tightly constrained laboratory experiments. We have a pretty good feel for what the forcing/sensitivity is as CO2 goes from 1880 concentrations to 2010 concentrations because its been measured and recorded. (Ignore for now that the forcing has been modified over the years as new data is recorded and graphs are imaged. Though this is testament to measurements and graphing, not underlying physics and mathematics.) We have no real world experience or measurement of what the forcing is for 350ppm going to 700ppm or 350ppm going to 1400ppm. Almost all of paleontology has temperature rising preceding CO2 increases. While this is very convincingly explained it none-the-less does not give foundation for accurately predicting CO2 leading temp from today’s levels. While we have good scientific hypotheses toward what maybe will happen as CO2 concentration goes from 350ppm to, say, 900ppm, we have no robust or rigorous science that will, with certainty — other than the opinion of learned scientists — assure us what will happen. Shoot! We can’t even assure that it will maintain its log relationship.

    We don’t know with rigorous and accurate science even the basic absorption profile. We have some good physical formulations with neat terms like HalfWidthHalfMax that are based on solid science — but as a general concept. When one gets into the real world with real molecules there are a couple of factors (called “n exponents” and “pressure-broadened half widths” e.g.) used in the formulations for instance that have to be assumed from various lab tests. While there has been much diligent effort coming up with these (HITRAN e.g.), 12 years ago the HITRAN CO2 variations were 0.49 to 0.78 for the n exponent and 0.055 to 0.095 cm^-1 for the base pressure-broadened half width. Really good stuff? I think so. Robust, rigorous and very accurate physics? I think dicey. Can’t confuse precision with accuracy. We can measure the width of the Atlantic ocean with a micrometer to great precision, but, drats!, not to great accuracy.

    In my studies I’ve come across these paraphrased quotes on just the pressure broadening part of radiation transfer:
    “Many methods of determining the pressure broadened line shape have been proposed. A particularly satisfying model is…. “, Zender
    “This is a fairly difficult subject…”, Tatum
    “The theory of this process is exceedingly complex, and in many regards incomplete.”, Pierrehumbert
    “….there is at present no general theory for the far-tail shape [of the Lorentz curve]”, Nicol
    “….such complex numerical calculations of atmospheric radiation may be flawed, may yield unphysical results, and competent investigators can disagree. An outsider can make no judgement. ….” Goody

    There’s a bit more but I’ve already far exceeded my welcome. Bottom line, IMHO while the general physics is solid there is a ton of individual assumptions, inferences and uncertainties in the specifics of “radiation transfer.” The science is quite good, but nowhere near slam dunk exact, robust or rigorous, and might not be precisely correct.

    • Rod B,

      In all practical physical sciences the professional competence is very much in being able to judge, which of the details are important for the question studied and which are not. It’s not possible to analyze everything equally well, but it’s certainly possible in very many cases to make good choices in the analysis and to get results that satisfy perfectly the goals of the study.

      Not every physicist understands string theory or is up to date with knowledge on modern semiconductors. Similarly not every physicist knows much about the details of radiative energy transfer, or numerical values for the relaxation time of vibrational energy of a CO2 molecule to the gas. Many concepts of physics are also idealizations, and often not strictly applicable to detailed questions. (Personally I knew little of the details a few years ago, as my own work on physics never involved physics of the atmosphere or other application, where this knowledge would be needed. I knew the basic theories, but little more. Based on personal interest, I have learned quite a lot more over the last couple of years.)

      Your question “Does the temperature of a gas rise when one of its molecules absorbs IR into exciting its vibration level — with no other changes?” is an example of question, which is certain to be interpreted in many different ways. Physicist with precisely the same understanding on, what is going on are likely to give different answers, because they interpret the question differently. Temperature is not well defined at the level of detail that answering that question unambiguously requires, but that is not a fault in the physical understanding, but in the question.

      Concerning handling of the saturation of absorption, we have again a case, where the knowledge is at a good level. Some inaccuracies certainly remain, but people who are specialists of the field can certainly estimate rather well, how large the remaining uncertainties of any specific application are. I’m not a specialist, but I know enough to be confident on the conclusion that the remaining uncertainties are insignificant compared to other uncertainties of the calculations, where the models of radiative energy transfer are used. That applies naturally only to the most competent scientists, there is no guarantee that any specific study does things correctly.

      Concerning the radiative balance of the Earth including its atmosphere, significant uncertainties remain concerning the actual state of the atmosphere, oceans, land areas, and ice covered areas. Even with perfect models of the interaction of radiation with atmospheric gases, the details of the balance are not known, when we don’t have detailed knowledge of the moisture level at every point, all details of clouds, precise knowledge on aerosols, and detailed description of the the temperature and emissivity of the surface at every point and for all relevant wavelengths. The knowledge of the physics of emission and absorption of radiation by atmospheric gases is much more accurate that the detailed quantitative knowledge of the state of the Earth system.

      Still we know enough also on the state of the Earth system to calculate with reasonable accuracy also the change in Earth’s radiative balance caused by an assumed sudden addition of CO2 to the atmosphere, when the (unrealistic) assumption is made that nothing else changes in the troposphere, i.e. the specialists can calculate with fair accuracy the value of the radiative forcing as defined in the IPCC reports.

  53. Tomas Milanovic

    Rod B

    [For fun, how many here say YES and how many say NO to the question: Does the temperature of a gas rise when one of its molecules absorbs IR into exciting its vibration level -- with no other changes?]

    Also just for fun. This question is ill defined .
    In reality:
    1) When ONE molecule absorbs IR, it increases its vibrationnal energy.
    2) On the other hand a temperature of a gas is only defined under rather restrictive assumptions – LTE (Local Thermodynamic Equilibrium) , energy equipartition , very large number of particles/molecules.
    3) From 1) and 2) follows that as one has only one molecule instead of a large number, no average energy can be calculated and therefore the temperature of a (single) molecule is undefined.

    If, in order to have well defined averages, one allows for a large number of molecules absorbing each an IR photon (and doing nothing else) then the answer would be NO.
    It is actually a tricky question because this innocently looking “and does nothing else” is an extremely non trivial assumption.
    As what a thermometer measures (e.g temperature) is the average kinetic energy of the molecules and as an IR photon absorption modifies only the internal vibrationnal energy, if nothing else happens, the average kinetic energy doesn’t change and a thermometer measures no temperature change.
    In non LTE conditions when the equipartition doesn’t work this is what happens – the molecules actually have 2 temperatures.

    One external measured by a thermometer and giving the average kinetic energy and one internal which is not measured by a thermometer but which can be defined by using the Maxwell Boltzmann distribution of the vibrational quantum states (there is a T in the law).

    The problem being that in non LTE conditions those 2 “temperatures” are very different .
    So while an IR absorbtion would obviously increase the internal (vibrationnal) temperature, it is a very difficult problem to say how much would the external (kinetic) temperature vary.
    In principle the latter would also increase but much less than the former.

    Btw I fully agree with your last paragraph :

    The science is quite good, but nowhere near slam dunk exact, robust or rigorous, and might not be precisely correct.

    It is an understatement.
    I have been working for 2 years on problems involving collisional relaxation and excitation.
    F.ex CO2 in an unexcited vibrational state will be vibrationally excited by a collision with another molecule like N2.
    That means that collisions play exactly the same role like IR absorption – they excite vibrationally the CO2 molecule and that’s what is for example the basis of IR lasers.
    However to answer even the simplest question : “What will be the distribution of the vibrationnal quantum states of CO2 initially in equilibrium after I inject in it hot N2?” necessitates a full quantum mechanical treatment with knowledge of the intramolecular interaction potentials.
    Useless to add that this latter is not known and only empirically fitted for the simplest diatomic and triatomic molecules.

    So everytime one reads that “radiative and colisionnal energy transfer is fully understood and pinacle of scientific knowledge”, one has to translate:

    The radiative and colisionnal energy transfer is poorly understood in the simple cases and not understood in more complex ones. However under simplifying assumptions (equipartition, LTE, homogeneity, steady states) and for simple molecules, one can empirically fit interaction potentials which allow for approximate numerical models to work.
    Under such assumptions and given that the Earth’s atmosphere is mainly constituted by simple molecules in LTE, these models can be fitted so that they do a reasonable job for a static Earth’s atmosphere in the validity range of the model’s parameters. But even in these simplified cases there are still unsolved and poorly understood problems concerning the wings of the absorption/emission lines

    • Thank you Tomas

    • Despite the uncertainty of the disposition of IR photon energy absorbed by a CO2 molecule, there must be some demonstrable statistical measurable heating effect. People keep saying there is experimental data without quoting sources. Any ideas where we can find the results of these laboratory experiments and the underpinning calculations?

  54. When AGW is found to be what it is and slowly dies, how are we going to pass our spare time?

    • There is more than enough corrupted science in other fields. AGW going down will liberate all science.

      • I don’t think any other scientific theory will come to ban the naked animal from using cheap energy. Unfortunately, unlike other animals, the naked animal is not born to naturally protect itself from the winter cold and summer heat. Those who advocate for a more expensive energy, are your really after the welfare of the naked animal?

    • Girma

      You ask:

      When AGW is found to be what it is and slowly dies, how are we going to pass our spare time?

      The new emerging “buzzword” is “ocean acidification” (or “OA”, for short).

      This is already being positioned as the new “impending disaster” brand when the thermometer all over the world (even those next to AC exhausts and asphalt parking lots) no longer play along with the premise that AGW is a “real and present danger”.

      Max

  55. Alan Millar

    “6. I then suggested that if we agree all these statements above, we must expect at least some warming.”

    Well there should definitely be agreement about that statement. It is demonstrably FALSE!

    Greenhouse gases are not a forcing factor in themselves they only act to amplify the radiative forcing of the Sun. Take away the Suns radiative forcing and you are not left with the Greenhouse effect forcing, you are left with zilch!

    The conjecture that the AGW crowd postulate is therefore that……
    ‘Increasing the radiative forcing on the Earth will cause temperatures to rise.’

    Well we know that not to be true. In the last 500 million years the Suns radiative forcing has increased by about 5% (about 65 WM2).
    However, the Earths temperature has not increased it has actually fallen from 22c to 14c.

    Now you can postulate any number of reasons why this has happened but one of the main planks of the AGW theory i.e. ‘Increasing the Radiative Forcing on the Earth will automatically cause temperatures to rise.’ is demonstrably false.

    You would have to have a clear understanding of all the current conditions of all the other climatic processes, connections, relationships. feedbacks etc etc etc to be able to say that and nobody is claiming that.

    Alan

    • Rob Starkey

      Alan

      With all due respect, what you write really does not make sense. The previous points outlined the ground rules. If all other factors REMAINED THE SAME, and there was an increase in GHG’s then there would be SOME additional warming. To disagree with that is really not a successfully arguable position. The sun may have a greater impact than many currently believe, but that does not mean GHG’s have Zero impact. To claim that is kind of like the creationists trying to prove the earth was “created 6000 years ago”- it is pretty darn difficult to demonstrate based upon science.

      The issue is how much in the real environment additional GHG’s (CO2) will warm the planet, is the really harmful to humanity in the long term, and what can and should be done.

      • I would argue that to agree( as opposed to “disagree”) with the points are more like creationists trying to prove the earth was “created 6000 years ago”. Creationist’s ground rules are that they can only use Bible for as the data and all other factors remained the same. They don’t take the real environment into consideration. It’s a closed system.

      • Alan Millar

        I am not sure what you are talking about.

        I am sure that everybody on the planet would agree that if the only process, that influenced the the Earth’s climate, that was changing was radiative forcing and all other effects and processes remained the same then the Earth’s temperature would change in lockstep with changes in that process.
        However, that is not the case so I am unsure what point you are trying to make.

        The current position of the AGW crowd is that ‘Increasing the Radiative Forcing on the Earth will automatically cause temperatures to rise’ and I have shown that is demonstrably false by empirical evidence.

        Alan

      • Rob Starkey

        Alan

        I try not to generalize the “AGW crowd” anymore than “skeptic’s crowd”, but we appear to be in substantial agreement if I understand your last message. It seemed that you agree that “in theory” additional GHG’s would raise the temperature if all other factors remained the same, but in the real world that is not possible. In the real world the changes in other variables have reduced the impact of the increased GHG’s to some point and we have not determined with any certainty the relationship under actual conditions.

  56. ‘Increasing the Radiative Forcing on the Earth will automatically cause temperatures to rise.’ is demonstrably false.”

    This is what I tried to tell Nick Stokes t’other day and he had a bad reaction to it. I’m not sure why. He never addressed the issue. Disappeared into the night.

    Andrew

    • Rob Starkey

      Andrew– when you write “automatically” into the groundrules, you are imo correct. Other factors could overwhelm the impact.

      • Rob,

        Also, after removing the “automatically”, the “will” in the sentence needs to be changed to “may”.

        Andrew

  57. So, the discussion has run to several hundred comments, and yet it seems that many people here, perhaps the majority, will not agree to these basic observations, even though from a scientific standpoint they are supported by overwhelming evidence.

    So what is the next step, for those who do agree?

    1. We could try other conditions, to try to find some list acceptable to all. But is seems unlikely that there is such a list.

    2. We could not discuss science with people who are not scientifically literate. The difficult here is that many of the ignorant/deluded people insist that they are scientific wizards and want to talk science, or rather, mix words and concepts they feel are “science-ish” in rather their political blather.

    3. We could, and I think this is likely the more practical solution, define three categories: pro-science (“warmist” “alarmist” or whatever label you prefer); “skeptic” (willing to accept the basic science, as expressed by the list, but identifying as a “global warming skeptic” or a “lukewarmer”; and “deniers” who do not accept the basic science.

    • Robert,
      Let us not forget the “true believer”, who is devoutly committed to the idea of apocalyptic climate changes caused by CO2; a person who rejects any critique of climate science and who defames skeptics by calling them anti-science; those who see dangerous climate change in the most trivial marginal data.
      IOW, you.

      • “Let us not forget the “true believer””

        I don’t forget him — he’s the guy calling himself a “skeptic” out of a mistaken belief that unquestioning, fanatical belief in one’s own opinions, accompanied by endless irrational attacks on other opinions, is “skepticism.”

  58. 5. Almost everyone in the room agrees that this is because of anthropogenic emissions (fossil fuels, cement production, forest clearance). We did hear Ian Plimer arguing that volcanic emissions of CO2 are more important than most scientists claim.

    JC comment: the anthropogenic contribution is (should be) undisputed. However, uncertainties in the global carbon budget do leave room for arguing about the relative contribution from fossil fuels.

    Everyone seems to equate CO2 EMISSION with CO2 ACCUMULATION in the atmosphere. Roughly half of current emissions are disappearing into carbon sinks. The IPCC’s projections aren’t transparent about the assumptions that are made when converting emissions into atmospheric mixing ratio and the uncertainty involved. The IPCC uses many emission scenarios, but no “accumulation scenarios”. Admittedly, we have control over emissions, but little control over the fraction that accumulates.

  59. Judith Curry has written:

    the evidence for the points where I presume close to 100% agreement is very strong and fundamental. That leaves plenty of room for legitimate and important disagreement on the other topics

    From the Wolff notes “close to 100% agreement” was reached for points 1, 2 and 4, with some dissention on point 3.

    But let’s see how the bloggers here responded to the list (as I have observed this here).

    1. CO2 does absorb infrared radiation, as observed in the lab

    Some posters here have commented that lab observations are not necessarily directly transferable to our climate system, but let’s ignore this for now.

    2. GHE does occur in practice

    No disagreement, except that some posters question how significant this really is in fact.

    3. GHE does not saturate with increasing CO2

    Here there is some disagreement as to whether the Beer-Lambert Law means the CO2/temperature relation continues to decrease exponentially or logarithmically or reaches a definite point of saturation beyond which added CO will cause no added warming. Possibly this has no impact over the range of CO2 levels we are discussing. Maybe someone who has better knowledge than I regarding this could comment.

    4. CO2 concentration in the atmosphere has risen significantly over the last 200 years

    Everyone here appears to agree, although some question the word “significantly”.

    5. CO2 increase is because of anthropogenic emissions

    Here there seems to be less agreement. Most would probably agree if the words “at least partially” were added.

    6. if one agrees to statements 1-5 above, one must expect at least some warming

    This premise starts of sith a large ”if”</em. But many of the posters here are not convinced that this statement is true, because of the uncertain impact of natural climate forcing or variability. Certainly the past decade has not demonstrated any warming, so why should the next?

    7. the climate has warmed over the last 50 years, for whatever reason

    Most posters would agree that this is what the record shows. Some have questioned why a 50-year period was picked out of a 161-year record and others have questioned whether or not the warming has been statistically significant.

    8. we probably don’t agree on what has caused the warming up to now, but it was not due to solar changes alone

    The first part is certainly true among the bloggers here, but the second part does not seem to have found general agreement. As JC commented: ”the role of solar variability on 20th century warming is not settled”

    9. sea level will rise if it warms

    This is too general to mean much. Many bloggers here do not conclude that the IPCC view of accelerated sea level rise due to AGW can be supported by robust data, some point out that ocean temperature has not warmed recently and others point to studies showing that the rate of sea level rise appears to have dropped significantly most recently.

    10. the likely range of warming from a doubling of CO2 is 2-4.5 degrees C

    As could be expected, this statement found no general consensus here. No one here felt that this range was an understatement, but many felt it was an exaggeration, based on recent physical observations, which point to a much lower range of 0.6-1.0 degrees C.

    So that’s how I observed that the bloggers here responded to the list.

    The best suggestion came from Dave Wojick, who suggested that a more basic list related more generally to climate change should precede the specific list addressing AGW questions only.

    Here is his list:

    S1. Climate changes naturally.
    S2. The mechanisms of natural climate change are not well understood.
    S3. The climate system includes many non-linear feedbacks.
    S4. These feedbacks are capable of producing counter intuitive behavior, surprises and unforced oscillations.
    S5. The climate is chaotic.
    S6. Chaotic behavior is intrinsically unpredictable.
    S7. We have no direct measurements of the major climate parameters over long periods of time.
    S8. The indirect measurements of climate parameters that we have are of unknown accuracy.

    JC commented to this list, agreeing in principle to all the points.

    Max

    • Max, thanks for your helpful summary

    • Nebuchadnezzar

      The S-list is a bit wooly and vauge too (what on earth is a ‘climate parameter’?) But hey! let’s add to it:

      N1. The mechanisms by which natural and anthropogenci change occur are not necessarily distinct.
      N2. Separating the effects of the two might not therefore be possible.
      N3. If it is, it will probably involve (brace yourselves) some kind of model capable of generating plausible counterfactual worlds.
      N4. Even if chaotic systems are intrinsically unpredictable, they are still predictable.
      N5. If we wait long enough we will have excellent measurements of all sorts of climate parameters, but it might not help.
      N6. Eggs
      N7. Milk
      N8. Fruit (not bananas)
      N9. Just because a problems complicated, we shouldn’t stop trying to understand it.

      (we have onions)

  60. Pekka (70498), Tomas (70512), I think you aptly described the pragmatic process of scientific investigation, but it doesn’t answer my point. You imply that good analytical scientists make good judgements for many things that are otherwise difficult to pin down. I agree. But it begs the common understanding of “rigorous and robust.” I further agree that priorities can and should be made on the degree of effort. If the current string theory proves goofy, nobody other than directly interested professional scientists are going to care much. And it will affect nobody’s life. But molecular radiation transfer is the lynchpin of CAGW, and we are debating possibly upsetting the fruit basket that will materially affect millions or even billions of people and cultures. I think this aspect of climate science deserves considerable effort to make it far more rigorous and robust than it currently is — assertions to the contrary not withstanding.

    A very simple example. Molecular level radiation transfer (absorption, emission, etc) analysis rests on Planck function and related theories and laws. Yet Planck’s function has virtually no involvement (at least directly) with it. By definition this can’t be rigorous and robust and exact. though one can intellectualize throughout the barnyard until it sounds exact. [That is NOT meant as a pejorative.]

    RE my question/poll: Your thorough analyses are logical, but I submit that the question is properly asked and can be answered directly within the realm of theoretical physics. For instance if one molecule in a mole was given some increase in its translation (kinetic) energy and no other changes within the mole are made, I can with absolute certainty (within known physics) assert that the temperature of the mole will increase. The fact that I can not measure it is not relevant (though it can be calculated albeit with much angst.) No one has ever measured the precise details of a Boltzmann distribution, either. So, I can properly pose the same question about increases in one molecule’s vibration energy. Or, if you can’t get past the single molecule increase, a quadrillion of them (but still having no other changes at that instant). Does the temperature (actual and real as defined, understood and agreed to by science, not an arbitrary parameter used for convenience in some constructs) rise?

    But, paradoxically you have I think affirmed my concern. The whole of GW rests on molecular absorption of radiation and transfer yet there is no clear definitive agreement if absorption into a vibration energy level adds to the temperature or not. Something is amiss. Maybe ala Pekka’s point it is a detail that matters very little in the final analysis. But when a scientist tells me I have to drastically change my lifestyle because of this thing called molecular radiation transfer, I would feel a lot more comfortable if I knew that he/she understood that theory every which way but loose — robust, rigorous and damn accurate. If he as an aside tells me the temperature (from the question) increases, then I will have a very difficult time accepting anything else he/she says.

    Tomas goes on to describe another area of considerable uncertainty (and he knows this area much better than I do), and this is the process and physics of collisional transfer. Tomas describes aptly many of the uncertainties. [One I might add: A CO2 molecule has a higher probability of colliding with another like CO2 molecule (given comparable concentrations), but we have little understanding why this is so.]
    This is also fundamental as it tells us how the energy works its way up to the TOA or conversely hangs around as heated atmosphere or maybe radiates back down to re-warm the surface. Unfortunately, while this process is based on reasonable science as Tomas states and is estimated with some precision, it is not robust and rigorous and we’re not really sure how accurate it is.

    • “there is no clear definitive agreement if absorption into a vibration energy level adds to the temperature or not”

      Rod – I agree with Pekka that the uncertainty in answering that question resides in its interpretation rather than an understanding of the physics. Consider a CO2 molecule adjacent to a thermometer. Imagine that the molecule becomes vibrationally excited either from collision or photon absorption. It then encounters the molecules of the thermometer and its energy is transferred to one of them. What will happen to the thermometer reading? Of course, if it relaxed via photon emission rather than collision, then eventually some other molecule would be the one that interacted with the thermometer, with the same result – an increase in the thermometer reading. Whether the temperature increased at the instant of vibrational energy increase in the CO2 molecule, or later, when the thermometer molecules were energized seems to me to be a semantic question rather than primarily a scientific one – at least as far as large scale average processes are concerned – because there would be no good way to tell the difference or for the difference to have a discernible impact.

      • Rod – I also noticed your statement: “A CO2 molecule has a higher probability of colliding with another like CO2 molecule (given comparable concentrations), but we have little understanding why this is so.]”

        I have not seen data supporting this claim. Can you cite a reference? Are you sure you’re not confusing this with the higher absorption coefficient exhibited by CO2/CO2 collisional self-absorption (as a form of continuum absorption)) than with absorption involving collisions between CO2 and a different molecule?

        Earlier, you stated, “Non-saturation is usually explained by the collisional broadening of the absorption profile that occurs with increased density”. That is incorrect as the major factor in non-saturation. That latter reflects the fact that at wavelengths further and further from the main CO2 absorption line at about 15 um, fewer and fewer CO2 molecules possess the energy states that allow them to absorb photons at these wavelengths. Consequently, more and more CO2 is needed to intercept radiation at these wavelengths before it can escape to space. The decline in absorption coeffiients as one moves away from the center at 15 um is roughly exponential, and is responsible for the observed and modeled ability of CO2 to continue additional absorption as the more saturated lines start to fill up, with a resulting roughly logarithmic relationship between CO2 concentration and radiative forcing over a large range of CO2 concentrations (although not at extremely low CO2 concentrations, and theoretically not at extremely high ones either).

      • Fred, if the molecule did not transfer its vibration energy when it collided with the thermometer, the thermometer would not read anything different than it did immediately before. If it does transfer its energy when it collides (with the thermometer or another molecule) the temperature rises. But this is one step more than the question I posed.

        It may be a semantic question. Or comparatively insignificant. But when the molecular radiation transfer expert is telling me I have to live in a hut because of what he knows, and I ask him a very precise and specific question in his field, and he answers, “it depends,” “It all depends on how you interpret the situation,” “It doesn’t really matter,” “you couldn’t measure it one way or another,” ["though I can measure if you've moved your butt into the hut!"] etc — WRONG ANSWERS. He either knows what he’s talking about or he doesn’t. And where he doesn’t he needs to explain that in gruesome gory detail.

        In the basic physics and equations for broadening, like molecules are more likely to collide (all else being equal) significantly enough that the physics is divided into two pieces: one called “self broadening” the other called “foreign (or sometimes “air”) broadening. Different effective cross sections are given to like molecules and calculated in the self broadening category. I think it’s as you describe…, I think.

        You have never heard someone say CO2 is not saturated because more CO2 increases the density and in turn collision and collision broadening?? I must have heard that or similar a hundred times. You, though, described the correct theory behind non-saturation.

      • Rod,
        You ask: “Does the temperature rise the instant the radiation is absorbed into vibration energy?”

        You tell that you really mean “the instant”, not what is the consequence after some time has been allowed to pass after the absorption. Your question implies also that you consider one specific occasion.

        The full answer by physics to your question is: “The system does not have a temperature at all under your restrictions, because the temperature is not a property of an individual system, where any detail is specified at microscopic level.” Any physicist, who gives another answer has not accepted your question as you have posed it, but replaced it by another question and answered that other question.

        From the fact that you have succeeded in formulating the question in a way that leads to the answer: “There is no temperature.”, you cannot draw any conclusions on the physicists ability to answer questions that are relevant for understanding radiative heat transfer in the atmosphere. The only correct conclusion is that your question is irrelevant for understanding the real issues.

      • fredmoolten

        Rod- I’m unaware of evidence that like molecules are more likely to collide than would be expected simply from the mathematics of their concentration. However, as I think you agree (from your comment), the probability of photon absorption is greater for self-collisions. The relevant phenomenon is continuum absorption due to the formation of temporary bimolecular dipoles, and not merely pressure broadening in the usual sense. As far as I know, the mechanism underlying the greater efficiency of self-collisional absorption is not well understood. In our atmosphere, continuum absorption involving water molecules appears to be a quantitatively more important radiative phenomenon than CO2 continuum absorption.

      • Somehow, I was logged in differently above from usual, which is why my name appeared in a different form.

      • Fred,
        Even without actual knowledge, I can guess, why water is different. Water has a rather high boiling point, because water molecules join easily together with a hydrogen bond. This is the reason for the relatively high boiling point of water, and its natural to expect that water molecules stick often together also in gaseous phase. A “supermolecule” formed by two or more water molecules has certainly a broad IR absorption spectrum.

        Similar effects are weaker for CO2.

    • Rod,

      Physics can analyze well, what happens to some volume of gas, when radiation is directed to it, but concepts like temperature have well specified meanings only in specific circumstances. The only really clear case is that of local thermal equilibrium, which means that the likelihood of finding any precise state of the system is proportional to exp(-E/kT) where E is the energy of that specific state and k is Boltzmann constant. Here the specific state means that all variables describing every particle of the system are given. When we extend the calculation to similar states that are not identical in all details, but have the same energy and appear alike, we must determine also the number of such states and multiply the exponential by that number. For continuous variables like velocity the discrete number of states is replaced by a density function of possible states.

      That same exponential is valid both for a larger system and for individual degrees of freedom. For the molecular velocities it gives the Maxwell-Boltzmann distribution, for vibrational excitations it gives the occupation level of the excited state. No single molecule has a temperature. It has several degrees of freedom with different energies. It’s moving with different velocities in x, y, and z directions, and it is in some vibrational and rotational state.

      The temperature can be determined for a large number of particles, but it’s better defined as a ensemble property. An ensemble is a collection of similarly prepared systems, not any single system at a single moment. If the system is in a stationary state successive states of one system are close to an ensemble. If the system is large and consists of many subsystems in similar external conditions, these subsystems are very close to an ensemble. In rigorous treatment of statistical thermodynamics all these issues are handled more formally.

      The problem here is not that the scientific knowledge would not be at a good level. The high level of knowledge applies also to interaction of CO2 molecules with IR. It has been studied both theoretically applying quantum mechanics and experimentally for different pressure levels to the extent that the remaining uncertainties are not a significant source of uncertainty in the analysis of atmosphere. The micro physics of these phenomena is known well enough.

      When I referred to the limited influence of imprecisely known details, I had mainly in mind the fact that the state of the atmosphere is not known precisely. Myhre and others studied in 1980’s and 1990’s how sensitive the estimates of the radiative forcing are for the details of the description of the atmosphere. Their conclusion was that it’s not sensitive at all. Reasonably good estimates can be obtained, when the atmosphere is described even roughly correctly.

      In place of the full line-by-line description of the absorption and emission more crude and computationally lighter band models give also closely similar results. The GCMs take advantage of this observation, as the computational speed is important for them. In general it makes sense to calculate best known physics so well that improving the accuracy would not change results significantly in comparison with uncertainties coming from other sources, but going beyond that would just slow down the scientific work. The uncertainties come mostly from factors that the science either doesn’t know or that cannot be taken properly into account with best effort. Thus the GCMs cannot be built solely from basic physics, but include also parameterizations based on empirical observations and discretization at a level that doesn’t allow modeling all important physics using just basic equations.

      All this brings back the point that many things are known well by basic physics, but cannot be taken as well into account in the analysis of the full real atmosphere. Some of the micro level phenomena are also difficult to analyze. Formation of clouds is an important example. Water doesn’t condensate to droplets of liquid or ice crystals without delay, when relative humidity exceeds 100%. The dynamics of that transition is highly dependent on additional factors. The role of aerosols is important, and cosmic rays have also some influence.

  61. Pekka, I much prefer the classic definition of true am_bient temperature of a system of (ideal) gases of T = 2/3(k)[average(rms) kinetic energy] — which of course is the result of manipulating the Boltzmann factor as you describe, ending with the Maxwell-Boltzmann distribution. In this context the Boltzmann factor deals only with the kinetic energy of translation.

    BTW, I think a single molecule can have temperature, though this fast becomes a philosophical or definitional question. If a molecule has translation kinetic energy it has temperature per the above, though I suspect you have to use arithmetic average, not rms, energy ala T = pi/4(k)[average K.E.]. I’m not sure what one can do with it. The temp certainly can not be measured or experienced. Though there are physics theories that start with the characteristics of a single molecule. Whatever.

    I don’t disagree with the thrust of your description of the science. But it is a matter of judgement, hopefully that is rational. You are satisfied that, “The micro physics of these phenomena is known well enough.” I still have unsatisfied questions. For instance, I agree that a ‘high level of knowledge applies to interaction of CO2 molecules with IR.’ But is it golden? The degree of absorption and transfer has been studied very precisely in a lab environment, but not so much in the real atmosphere environment. Despite the thoroughness of the lab tests, atmospheric forcing equations have been developed with small degrees of trial and error and historical matching of observations (otherwise known as curve fitting which can in fact be proper and not nefarious as it is so often implied). The log relationship stems from absorption and optical length exponential laws; yet even as we speak log relationships do not apply to all greenhouse gases. While, again, tests have been made in the lab, we have no observational experience, actual or by proxy, to validate forcing from CO2 concentration increases leading temperature from say 500ppm to 1000ppm. The forcing that we have observed, 280 to 560 (though not even all of that) is said to be 5.35ln2 = 3.708 w/m2/doubling, not including feedback which is really loosey-goosey, but this is still rough around the edges and subject to refinement, Myhre’s et al confidence not withstanding. Why should I then accept its applicability to future never observed situations as golden? Likely pretty good, O.K. But not iconic.

    Collisional energy transfer has also been thoroughly studied, yet as Tomas M describes in 70512 there are large important pieces that is understood poorly. As I cited in 70460, in the critical field of pressure broadening there are numerous textbook-writing strong AGW proponent scientists who say it is very complex, hard to understand and pretty loose.

    This doesn’t mean that the overall science is lousy — it is not… it is quite good. You say good enough; I say not… not yet… not moving into the hut, selling my SUV, changing jobs (even if I could), canceling my unaffordable yet intermittent electric service yet.

    However, I agree in general with your words, “In general it makes sense to calculate best known physics so well that improving the accuracy would not change results significantly in comparison with uncertainties coming from other sources, but going beyond that would just slow down the scientific work.” But it still remains a judgement. It’s possible yours is too premature; it’s possible mine is too picky and tenacious, and we’ll all die while I’m waiting. I hope not; but I have to call ‘em as I see ‘em, and in this particular are I see too much missing important stuff.

    • Rod B, as has been mentioned, temperature, like pressure and density, is a statistical property of many molecules. The science is not called statistical mechanics for nothing. So just like you can’t say an individual molecule has pressure or density, you can’t say it has temperature. Only part of its temperature is in its kinetic energy, because some would be in rotational states, and some fraction of molecules would additionally have higher vibration states. These states all are part of its heat capacity properties, meaning energy is partitioned among these states.

      • Jim D, How many molecules do you need then before there is temperature? Two? one hundred? ten billion? If 10,000,000,000 is it, why not 9,999,999,999?

        You’ve aided one of my other points. For the record, the answer is (drumroll): vibration and rotation energy do not effect temperature of a gas.

      • The answer is: how many does it take to get a Maxwell-Boltzmann distribution? Maybe a million? This would be a few cubic nanometers of air.
        Vibration and rotation affect its heat capacity. At a given temperature these states allow molecules to store more energy, or alternatively make it require more energy to warm a gas by a given temperature difference.

      • That description of vibration and rotation is correct.

      • Jim and Rod,
        That’s not the full definition in statistical thermodynamics although your comment on heat capacity goes to the right direction. Temperature is a property of a subsystem (or an ensemble of subsystems) in local thermal equilibrium. Local should be interpreted to relate to the strength of couplings within the subsystem and the rest of the world. I.e. we must define the boundaries of the subsystem so that its thermodynamical properties are not influenced rapidly by the outside world in comparison with reaching the stationary probability distributions within the system. (There are cases, where the subsystem, whose temperature is considered is not spatially separate from the rest of the world, but is interacting for other reasons weakly with the outside world in comparison with the internal interactions. I wrote my first scientific paper on such a situation.)

        In air the rotational and vibrational states of CO2, H2O and other molecules are strongly coupled to linear motion. Thus the temperature is defined only, when all these vibrational and rotational modes are also in thermal equilibrium – as they are always in practice, but not in the question of Rod B. Therefore the question is not valid, and the only correct answer to it, is that the question is not valid. The thermal equilibrium for vibrational states is represented by the discrete probabilities of finding a molecule in each of these states, or occupation levels of these states, to use the word I have used before.

        Maxwell-Boltzmann distribution is a partial answer to the question, because it describes the distribution of velocities, but doesn’t tell about other degrees of freedom.

        How large the system has to be to have a temperature? There are no unique answers. The answer depends on the types of interaction that the subsystem has with the environment. It really goes back to what I wrote above: The subsystem must be so large that the interactions within the subsystem are much more common than those with the outside world. To satisfy this requirement the gas volume must have dimensions that are large compared to the mean free path, which is 68 nanometers in air at the pressure of one atmosphere. Thus the required volume would have dimensions of the order of 1 um, or a volume of 10^-18 m^3. That volume contains 27 million molecules.

      • Pekka, as far as I know you describe accurately the physics of Local Thermo Equilibrium and its involvement /determination of temperature. But I think the precise physics over-intellectualizes the science to the point that “temperature” becomes an abstract with minimal physical connection. I might almost prefer: “temperature” is that property of a system that makes it feel warm or cool .

        The definition seems like temperature is non-existent unless the subsystem or ensemble is in LTE. So if you have a system that is not quite at LTE for whatever reason it can not have “temperature,” which is absurd in any meaningful sense of the term.

        Temperature being defined from a derivative of LTE I’ll submit is technically correct, but a problem exists in that LTE can take on a number of definitions itself, making “temperature” somewhat elusive. Is a mole of gas in LTE when particles in the mole have different energy levels? That’s probably not too hard to get around as many logically define LTE (in this environment) as the mole of gas following the Maxwell-Boltzmann distribution. Is molecular equipartition required? Probably not as equipartition is far more loosey-goosey than LTE. Most say the M-B distribution also includes the Boltzmann factor which says the internal energy states must be occupied to the degree given in the Boltzmann factor. Though that raises a question since temperature is an independent variable for the B-factor.

        Actually that last part doesn’t concern me; it fits in with my assertion… kinda. If the number of vibration states filled is less than what B-factor says, then those states will get filled in respective molecules by picking up translation energy from themselves or via collision. This process will lower the temperature until the Boltzmann factor is satisfied. Then the mole will be in LTE and the end temperature is The Temperature as determined by M-B distribution of the K.E. — kT equivalence dictates. One difficulty, however, I repeat: how would one know it was out of LTE initially because the Boltzmann factor (percentages of molecules in the various levels of excited states) was unsatisfied since we don’t know if the Boltzmann factor is actually out of whack because we have to know the am_bient temperature to know this, which we can’t know… I think… because we don’t have LTE.

        Does this say, as has been said, that my question: does exciting one (or a bunch) of molecules in a mole that is in LTE raise the temperature or not? become moot because the mole is no longer in LTE so we don’t now know what the temperature is…. or it doesn’t have temperature… or…..? This intellectualizing of the concept, while maybe technically accurate and maybe even helpful for some problems or analyses, makes minced meat out of the basic idea. I used to know about what the temperature of my back yard was by reading the thermometer attached to the kitchen window. Imagine my chagrin that I only knew the temp in a cubic micron or so abutting the thermometer, and not out in the yard. Shoot! My yard is so out of LTE it can’t even have a temperature!

        I think the temperature of a gas at any instant ought to be determined simply by the rms average of the kinetic translation of the molecules in a gas, and as that relates to the kT factor.

        Apology: My smart-alec writing style is meant to make it clearer. It is not, nor meant to be derisive of your posts which I respect. And sorry for the wordiness.

      • Rod,

        If you wish to have a definitive and correct answer, you must accept all the complications of discussing canonical or macrocanonical ensembles, which goes even further than LTE.

        Other alternative is that you are satisfied with something, which is not precise, but not too far from the truth either, but then you cannot insist that people should agree, what is a suitable simplification, and you cannot complain on any weaknesses in the answers.

        Then you ask further questions on what is required including equipartition and other issues. The whole thing starts to get far too complicated for this discussion thread. If you really want to understand things at that level then I think that the only possibility is to study a good textbook of statistical thermodynamics (I am not up-to-date with offerings in that field and cannot tell, what would be a good textbook).

        If you have some specific problems, you can contact me through my blogs “Random topics” or by email to address that you can find from the site. Continuing here doesn’t seem to be the right way.

      • “macrocanonical” should be “grand canonical”.

      • I agree that just using KE you can define the temperature of a gas, assuming it is also in an MB distribution indicating LTE. In a situation where you added energy to a sub-set of the molecules, it might be a bi-modal distribution temporarily, not MB, making T difficult to define for the gas as a whole.
        As an aside, with lased gases you can get a “negative” temperature as defined by the atomic energy state having an inverted population, so there is that definition of temperature too, but mostly in natural states the two agree.

      • Looking at kinetic energy gives usually the right temperature, but then one is not allowed to add statements like “one molecule is in vibrationally excited state” and expect that such fact can be discussed without loosing the concept of temperature.

    • Rod,

      In classical thermodynamics defining temperature is difficult. The concept is totally dependent on thermal equilibrium and it’s defined essentially as what a thermometer in thermal equilibrium with the system shows.

      In statistical thermodynamics the temperature is still defined only for a system in thermal equilibrium, and that requires that all degrees of freedom have the same exponential relationship between the probabilities of finding the particle in each specific state. A single particle in a specific state doesn’t have a temperature. Some descriptions of thermodynamics may not tell that, but that means that they are sloppy or use implied unstated assumptions concerning ensembles.

      You may get wrong answers from physicists, who are themselves sloppy or who have not had good education on this point, but all that’s not an argument concerning correct physics. On these principles Tomas seems to agree fully with me, although he emphasizes some further issues somewhat differently.

      Concerning line broadening the practical calculations are approximate, but line shapes can be handled well enough for needs of the calculation of radiative heat transfer in Earth atmosphere. At very high CO2 concentration the accuracy would be worse, as far tails and continuum absorption start to influence the results, but that’s not a problem for Earth atmosphere. (Calculations of Venus atmosphere are subject to more uncertainties, but fortunately that doesn’t influence us.)

      Concerning the practical calculations I don’t have much else to add to my earlier comments.

      • Out of curiosity (and I know this is being drug through the mud, so maybe just for fun), in theory (forgetting the practicalities of very tiny measurements) if you had an inelastic completely insulated thermometer in steady state, and a completely elastic box containing one N2 molecule with some kinetic energy, and you stick the thermometer into the box, wouldn’t eventually the N2 collide with the thermometer and would not the temperature measured by the thermometer increase?

    • @RodB ” The degree of absorption and transfer has been studied very precisely in a lab environment, but not so much in the real atmosphere environment.”

      Can you or anyone point me to such studies? Absorption spectra seem well studied. Heat transfer to gases after IR absorption – haven’t been able to find anything, nor has anyone come to the party with any clues yet. (I wanted to know how an IR laser behaves when shining through a gas containing various concentrations of CO2, especially to quantify the “backradiated” and “absorbed” proportion and a mathematical theoretical justification.)

      • Databases like HITRAN make use of extensive lab test along with their heavy theoretical calculations to come up with their parameters on an on-going basis. I know this for absorption, but I can’t really back this up (though I think it’s true) for actual molecular cascading collisional transfer.

      • The knowledge of IR absorption spectra is not used only in climate science, and the climates science is not the first major application and motivation for the related computer codes. They were developed for remote sensing and reconnaissance applications on both military an civil sides All these uses verify the accuracy of much of the data.

        The data and the models are also verified by the measurements of downwelling IR radiation at surface and satellite observations of IR radiation to space.

        I cannot provide any specific references, but the understanding of the mechanisms and the correctness of the data has certainly been validated in many different ways both by laboratory measurements and by observing real atmosphere.

      • Aren’t measurements of downwelling IR radiation at surface extremely sparse? At least on a line-by-line basis?

      • Rod,
        How many of them would you need?

        The whole idea of physical sciences is that it produces results that can be generalized. The details are determined by the most accurate methods like laboratory measurements and in areas, where theories are considered accurate they is used to calculate, what is expected to happen in other cases. Other measurements are made for various reasons including the wish to verify that the expectations are indeed true and that nothing essential has been left unnoticed. Even a rather small number of measurements of downwelling radiation provides such a verification, but only within the limits of knowing the state of the atmosphere above the points of measurement.

        When the results are of importance for applications dependent on accurate measurements these practical applications form often ultimately the strongest evidence that the understanding is correct. Many remote sensing applications are such in case of absorption of IR radiation. Again the evidence given by any single observation is limited, but put together their are a significant verification.

        For phenomena that are as simple as the interaction of radiation with gaseous matter the above approach of physical sciences has been extremely successful. Physicists have learned to estimate well enough, where the method gives results reliable enough for various practical purposes. They have good reasons to be confident that the basic theories like Quantum Mechanics and theories of electromagnetic radiation are valid over very wide range of situations. They have also good reasons to believe that many macroscopic phenomena can be calculated from this basic knowledge and to determine, whether a specific situations falls in this class. The calculation of the interaction of radiation with atmospheric gases belongs to these situations, when the state of the atmosphere is known or assumed. By the state I mean temperature profiles, concentrations, and the influence of clouds. Determining accurately the state of the atmosphere is more difficult, but fortunately the most important results of radiative calculations are not very sensitive to all details of the state of atmosphere.

      • Apparently military rangefinding CO2 lasers uses IR light because “the atmosphere is quite transparent to IR light” http://en.wikipedia.org/wiki/Carbon_dioxide_laser

      • If you continue to the linked Wiki article on LIDAR’s yuo’ll notice that the wavelength used is not that of the main CO2 absorption peak of 15 um where the atmosphere is far from transparent to IR. At 15 um the radiation is stopped almost totally within a few hundreds of meters and significantly by the first tens of meters. The influence of the emission and absorption by CO2 is so strong that the small handheld IR thermometers filter these wavelengths off to get better accuracy in determining the temperature of the surface being measured.

      • So how much of the IR radiated by earth and water does and does not fall into the CO2 absorption peak??

      • Approximately 10% of IR radiated by Earth surface or 40 W/m^2 gets trough without being absorbed by the greenhouse gases or clouds.

      • But clouds happily block all light relatively unselectively. And some/many/most wavelengths of IR are passed by an atmosphere seen as transparent to IR for other purposes.

        The question was how much IR radiated by earth and water does and does not fall into the CO2 absorption peak?

      • Most of it, of course, but so what?

        Seeing questions like yours, I have a strong feeling that the answer will be misused to imply something that it doesn’t mean. I hope you don’t prove once more that my feeling was justified.

      • The answer will be used in the defence of science. So where is the empirical laboratory evidence to support the assertion that CO2 absorbs the amount of IR energy that is claimed??

      • Look it up. We are not here to do your homework for you.

        Feel free to report back with your findings.

      • On the absorption and radiation of heat by gases and vapours, and on the physical connexion of radiation, absorption, and conduction.—The …
        J Tyndall – Philosophical Magazine Series 4, 1861 – Taylor & Francis

      • Still can’t find the empirical laboratory evidence I’m looking for.
        Tyndall wrote last in “Contributions to molecular physics in the domain of radiant heat ” http://www.archive.org/details/contributionsto03tyndgoog

        Tyndall’s observations on gases are limited to the range of 0.5 to 3.5 inches of mercury pressure (which is substantially higher than atmospheric levels of about 0.3mm Hg or 2.4% of the levels measured). He also observes radiation emission by various gases to be similar to “absorption”. It is noted Tyndall’s experiments measured “failure of transmission” rather than specifically “absorption”.

        Study of the infrared atmospheric window clarifies the situation somewhat. http://en.wikipedia.org/wiki/Infrared_window
        From the graph it looks like net about 40-5% of all IR is transmitted by the atmosphere.

        A GHG model run on SpectralCalc suggested CO2 doubling sensitivity of 0.22degC.

        http://climateclash.com/2011/04/04/g12-carbon-dioxide-an-innocent-bystander-in-climate-change/

        How is one supposed to know which model is more correct other than by prediction/measurement/falsification or by experimental verification?

  62. Pekka, et al: This has become very prolonged and gotten a little silly (my fault), but IMO is critically important and on topic with this thread.

    The problem with the LTE-based definition of temperature is that, at the molecular level, which radiative transfer concerns itself with, LTE is an abstract. It explicitly makes no sense (and doesn’t try to) at the molecular/atomic level; as stated it only has utility at the system, subsystem, or ensemble level. However at those levels, in the atmosphere, LTE does not precisely exist. It can only be assumed on a broad kind of average condition, which abrogates its utility in molecular level analysis.

    In the nanosecond that a photon is absorbed by a CO2 molecule, the subsystem, however small you make it, is in the strictest sense (including Boltzmann distribution in addition to Maxwell-Boltzmann distribution) no longer in LTE. 10-100 nanoseconds later when the molecule relaxes by transferring its vibration energy to another’s translation energy, LTE returns (given a sufficiently small system). However if a few microseconds pass without collisional relaxation and now a photon is emitted instead, LTE again returns. But for those entire microseconds the system was not in LTE.

    The question is: for those microseconds (and in fact for some time beyond) what was the temperature of that subsystem of atmosphere? To say we can not know because the system was out of LTE evades with a strawman (albeit technically valid) the physical answer with an abstraction. This might be O.K. in other more philosophical circumstances. But here we are trying to assess the fundamental crux of global warming: the process of a CO2 molecule absorbing some radiation and converting that into real temperature.

    As I’ve said before, if us laymen or scientists with no GCM and access to supercomputers have to rely on expert knowledge, that knowledge, given the magnitude of the consequences, ought to be extremely precise and near exact. If the expert doesn’t know if absorbed radiation into vibration per se affects or effects the temperature of the system or not — and evading the answer with an abstraction is equivalent to not — there is a major hole in the robustness and rigor of this aspect of climate science. And this aspect is of fundamental critical importance to AGW.

    One might say it does not make any difference since in the preponderance of cases there is only a few nanoseconds where there is doubt. That may be true, but I will put my faith more in the expert who gives the correct answer for all of the critical pieces, not the one who offers an incorrect answer or no answer at all (also incorrect) albeit in just a “small” piece of the puzzle.

    • Rod,

      There are no problems in combination of radiation, vibrational excitations, thermal motion, LTE and temperature. They are all perfectly valid concepts for the atmosphere. The temperature is continuously well defined, there is all the time absorption and emission of the absorption, a few percent of CO2 molecules are always in vibrationally excited state, and all this is fully consistent with LTE and a well defined temperature.

      The only thing that is not consistent with all this valid physics is your question. You insist to know, what the temperature is in a state that you specify so accurately that the specification makes LTE impossible and therefore the temperature non-existent. When you wish to discuss thermodynamic quantities, you must accept that you cannot at the same time ask too detailed questions about a single molecule.

      • “absorption and emission of the absorption” -> “absorption and emission of radiation”

      • Pekka, my problem and point remain. You just said of a subsystem of many CO2 molecules that has been in LTE, and just now (t = 0) a few molecules (or maybe one) absorbed radiation into their vibration energy, currently (t = 0+), for that subsystem, “the temperature [is] non-existent.” That won’t fly, Orville! (Or where did it go??!!??)

      • “Or where did it go?”

        You took it off. Temperature is a statistical property and statistics cannot be applied, when the state is defined so narrowly that there is no space for statistics. (Or the temperature is a property in classical thermodynamics, where nothing is known on micro level.)

        You may say that I have this one molecule in excited state, and it hasn’t been in interaction with the rest of the system, and ask what has happened to the temperature of the rest of the system. The answer is of course that it hasn’t changed. But you cannot ask what has happened to the temperature of the whole system including the single molecule, whose state you know.

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