by Judith Curry
How should we interpret the record low minimum sea ice extent?
Summary of Observations
Here is the basic story from the observations:
On Aug 26, the Arctic Ocean seasonal minimum sea extent surpassed the previous satellite-era record minimum set in 2007 (4.17 M sq km). The current sea ice extent is below 4 M sq km, and apparently a minimum has not yet been reached, although a minimum around 3.5 M sq km seems likely.
The Arctic sea ice extent undergoes a pronounced annual cycle, with maximum extent of about 14 M sq km in March. In the 1980’s and 199o’s, sea ice minimum extent (in September) averaged about 6.5-7.5 M sq km.
The 2007 minimum ice extent was also associated with a new record in ice volume (which includes ice thickness). Minimum ice volume records were also set in 2010, 2011, and now 2012, with the current ice volume tracking slightly below the 2010/2011 values.
Causes/attribution
For background on this issues, see my previous posts:
- Pondering the Arctic Ocean. Part I: Climate dynamics
- Likely causes of the recent changes in Arctic sea ice
There are three main theories for the recent decline in sea ice extent and volume:
I. Greenhouse induced ‘spiral of death’: Mark Serreze and Peter Wadhams are the primary proponents of a rapid spiral of death. The main idea is that melting triggers more melting through the ice albedo feedback mechanism. The evidence for this theory seems based on ‘trendology’ of observed sea ice extent and volume. Spiral of death proponents project faster melting than climate model projections. More moderate versions of this theory rely primarily on climate model projections of sea ice and acknowledge a significant amount of noise from interannual variability.
II. Natural variability only: Joe Bastardi is one of the chief proponents of this theory, see his recent article. This is basically an argument whereby the PDO and AMO set up ocean circulation patterns that are melting the sea ice.
III. Climate shifts hypothesis: JC is a proponent of this (see my previous post) new evolving theory. This hypothesis is based on the network synchronization ideas of Tsonis et al. and bifurcation analysis (e.g. Livina and Lenton). In the particular instance of the past 5 years of low summer sea ice, it seems that the shift in sea ice characteristics was induced by a combination of local factors and hemispheric indices.
Livina and Lenton have a new paper that lays out some of these ideas: A recent bifurcation in Arctic sea ice cover. From the abstract:
Here we show that a new low ice cover state has appeared from 2007 onwards, which is distinct from the normal state of seasonal sea ice variation, suggesting a bifurcation has occurred from one attractor to two. There was no robust early warning signal of critical slowing down prior to this bifurcation, consistent with it representing the appearance of a new ice cover state rather than the loss of stability of the existing state. The new low ice cover state has been sampled predominantly in summer-autumn and seasonal forcing combined with internal climate variability are likely responsible for triggering recent transitions between the two ice cover states. However, all early warning indicators show destabilization of the summer-autumn sea-ice since 2007. This suggests the new low ice cover state may be a transient feature and further abrupt changes in summer-autumn Arctic sea-ice cover could lie ahead; either reversion to the normal state or a yet larger ice loss.
Mike Wallace combines the regime shift idea with the spiral of death theory:
I view the question of whether the minimum sea ice extent sets a new record this year as secondary. The important news is that in five summers the sea ice extent over the Arctic Ocean has not recovered significantly from its precipitous decline in 2007. This is one of the clearest examples of what appears to be a regime shift in the recent historical record. I think we still need to be open to the possibility that natural variability has played a role in the recent warming of the Arctic and that the summer ice could come back, but with each year that goes by without a return to the pre-2007 summertime Arctic climatology it seems a bit more likely that the remarkable change that we have witnessed will prove to be irreversible on a human time scale.
- Thickness and compactness of sea ice at the beginning of the melt season: ice that starts out thinner is more easily melted away. Further, first year ice has different optical and thermodynamic characteristics than multi-year ice.
- Transport of ice through the Fram Strait (between Greenland and Europe), which depends on a combination of atmospheric and ocean circulation patterns
- Weather patterns that act to either break up or consolidate the ice
- Radiative forcing (which is dominated by the cloud patterns)
- Melting from below by warm ocean currents.
- Melting from above by warm atmospheric temperatures.
- Geographic distribution of the sea ice, which depends on a combination of all of the above
Do check out Steve Goddard’s Real Science – stevengoddard.wordpress.com – where you will find article after article from the past 100 years about the Arctic ice melting massively.
It would seem to me that in terms of climate and the globe, when a recording of events only started 30 years ago, to talk of “records” is grossly misleading.
BTW, Judith – kudos for your Lewandosky put down. The man needs medical treatment; he is not at all well.
While Goddard’s anecdotes are interesting there’s plenty of more concrete compiled data covering the last 100 years, which suggest sea ice levels today are lowest for over 100 years:
http://www.skepticalscience.com/record-arctic-sea-ice-melt-to-levels-unseen-in-millennia.html
The Medieval Warm period was more than 100 years ago and the Roman Warm period was more than 100 years ago. Sea Ice Levels are much like they were in the many warm periods of the past ten thousand years.That is how it works. Earth gets warm and then Earth gets cool.
And yet we have observations that show large variability against a small trend and decadal shifts in trajectory.
http://s1114.photobucket.com/albums/k538/Chief_Hydrologist/?action=view¤t=chylek09.gif
http://s1114.photobucket.com/albums/k538/Chief_Hydrologist/?action=view¤t=arcticice-1.gif
But there are also quasi 1500 year transitions.
‘Evidence for abrupt climate change is readily apparent in ice cores taken from Greenland and Antarctica. One sees clear indications of long-term changes discussed above, with CO² and proxy temperature changes associated with the last ice age and its transition into our present interglacial period of warmth. But, in addition, there is a strong chaotic variation of properties with a quasi-period of around 1500 years. We say chaotic because these millennial shifts look like anything but regular oscillations. Rather, they look like rapid, decade-long transitions between cold and warm climates followed by long interludes in one of the two states.’ WHOI
We know why it happens in principle – multiple negative and positive feedbacks in a complex and dynamic system. You should remember that – tremendous energies cascading through powerful mechanisms in a thermodynamically nonequilibrium system. We are a bit short on detail.
I think this blog is somewhat above Cook’s propaganda. Those pre-satellite ice measurements were not made in any scientific way and to attach them to the satellite measurements smacks of the Mike’s trick. To put faulty data on a graph does not make it accurate. I would believe the unsolicited newpaper reports over Cook anyday.
lolwot, considering that 100 years ago appears to have been colder than normal, I would expect Arctic sea ice extent to be greater than normal in the past 100 years. 150 years ago may be a different story since that seems to jibe with the Greenland melt. There has been a lot of land clearing, city building and failed world domination going on since then. Plus some more CO2 is in the air.
SkepticalScience does not allow open questions. It pure propaganda. Its like you use The National Enquireror as you source.
No – SKS does allow open questions – however with the caveat that they are courteous, not filled with insinuations and in the appropriate thread. They are very strict with these rules but I understand why – there are far too many people out there who think that when they post a hate-filled comment that contains insinuations and personal attacks mixed in with some questions – that they deserve to get an answer – I don’t believe that – you should only get answers if you’re not a prick about it – most people who complain about SKS moderation are people who were repeat offenders in these categories.
Comparing the National Enquirer to SkS! Why defame the Enquirer?
R, insinuations like internet polls are not very scientific?
Didn’t that judge for FOI and UVa last week say that the global warming industry’s preferred tactic of argumentum ad hominem?
Hateful comments is your side. The court agrees.
Jeremy Poynton,
Good points: it’s all happened before. In fact there has been no ice at either poll for 75% of the time since multi-cell animal life began on Earth. So the important question we should be asking is: so what?</i?
Judith asks:
My answer is to ask those who are concerned about the changing ice extent: So what?
What is the relevance of it?
What is the significance of it?
How does it change the cost benefit analysis of climate change?
How does it affect policy?
What difference does it make to what I see as the three main parameters that affect cost benefit analyses and there for the main effect on policy decisions?
They are (IMO):
1. The damage function
2. Climate sensitivity (T2xCO2)
3. Decarbonisation rate
How does Arctic sea ice extent affect these three key inputs to cost-benefit analyses?
Science is not relevant? There has never been ice free poles during the Quaternary and the ice continues to accumulate season by season. The Quaternary is the critical period and even now we are only talking about ice free oceans in the Arctic summer and still a ways to go. Sometime in the long slow drift of continents following the breakup of Gondwanaland – conditions became ripe for the repeated glacials and interglacials that we have seen for the past few million years. North and South America joining at the Isthmus of Panama? The tectonic uplift of the Himalayas? Whatever the reason it changed the climatic pattern to abruptly evolving cold and warm periods.
The essential condition may be orbital cycles and slow changes in insolation in high latitudes – but the glacial trigger is likely to be warmth itself freshening and warming the Arctic ocean. The increased evaporation deposits snow on high altitudes that survives the summer in lower insolation periods accumulating and reflecting more of the suns energy back into space. Heat transport to northern climes slows. At some point there are runaway feedbacks of ice and snow that plunge the world into a glacial in as little as a decade.
So to answer your 3 points.
1. The damage function could be quite severe. Ireland with the climate of Lapland. Glaciers hundreds of metres deep across North America, global drought as evaporation slows to a trickle. This is a future seriously worth thinking about.
2. Regional and variable climate sensitivity. This is not a question worth thinking about in terms of policy.
3. Decarbonisation as rapidly as is cost effective. We need to build richer and more resilient societies and to have cheap and abundant energy.
Robert I Ellison,
Only if you are a cherry picker.
The fact that the Earth has spent 75% of its time at a much warmer temperature than it is at now shows that warming will not be catastrophic. For example, the oceans are not going to evaporate as James Hansen would have us believe. That is an important point – i.e. warming is not a threat with catastrophic consequences.
Secondly, life thrives when the planet is warmer and struggles when colder. Another very important point that demonstrates that warming is not catastrophic.
Therefore, since catastrophe is not a real threat, we are left with addressing the question: what are the costs and benefits of warming versus the costs and benefits of mitigation policies?
The policy issue is about the economics of adaptation versus mitigation.
Your comments about the three key inputs to the economic analyses suggest you may not have understood what I was referring to. To repeat, they are (IMO):
1. The damage function [DamCoef]
2. Climate sensitivity [T2xCO2]
3. Decarbonisation rate [g(CO2/GDP)]
Refer to Nordhaus A Question of Balance to get an understanding. In particular refer to Table 7-2 (p130)
http://nordhaus.econ.yale.edu/Balance_2nd_proofs.pdf
Nordhaus ‘A Question of Balance’, Table 7-2 (p130)
http://nordhaus.econ.yale.edu/Balance_2nd_proofs.pdf shows that it is the ‘Damage Function” not Climate Sensitivity that is the cause of the greatest uncertainty in the cost-benefit analyses of projected climate change scenarios and carbon pricing policies. Therefore, more priority should be placed on reducing the uncertainty in the Damage Function and less on trying to improve the uncertainty in the climate sensitivity.
Nordhaus (2007) ’Accompanying Notes and Documentation on Development of DICE-2007 Model’ http://nordhaus.econ.yale.edu/Accom_Notes_100507.pdf Section VII, p24, ’Lab notes for Impacts and Damage Function’ says:
The lack of data allows CAGW alarmist, like Ross Garnaut, a great deal of room to exaggerate and make alarmist pronouncements about the impacts of global warming. Ross Garnaut (and John Quiggin) overstated the impacts of warming in arguing the case for the Australian Labor Party’s carbon tax and ETS for Australia.
The following is an example revealing how they exaggerated the impacts of sea level rise. (extracts from this:
http://www.climatechange.gov.au/publications/coastline/climate-change-risks-to-australias-coasts.aspx )
The report states that the high end of the IPCC’s AR4 estimate of sea level rise is 79 cm by 2100, but does not mention the central estimate. Then it says:
It then says:
And says:
But, there is no proper estimate of the damages, let alone proper discounting applying over 100 years, and no allowance for the fact that infrastructure is continually renewed, upgraded, adapted for changing conditions.
The report was developed to justify the Australian carbon tax and ETS. It uses scaremongering and exaggeration. In this way it has followed the precedent set by the Stern Review for the UK Labor Party.
The Garnaut Climate Change Review is a political document. It is a scaremongering document through and through. It should be dismissed.
Well no Peter – it is you who do not understand and simply repeating your points is not going to make them any more rational.
Let me quote again from the Woods Hole Oceanographic Institute.
‘Thinking is centered around slow changes to our climate and how they will affect humans and the habitability of our planet. Yet this thinking is flawed: It ignores the well-established fact that Earth’s climate has changed rapidly in the past and could change rapidly in the future. The issue centers around the paradox that global warming could instigate a new Little Ice Age in the northern hemisphere.
Evidence for abrupt climate change is readily apparent in ice cores taken from Greenland and Antarctica. One sees clear indications of long-term changes discussed above, with CO² and proxy temperature changes associated with the last ice age and its transition into our present interglacial period of warmth. But, in addition, there is a strong chaotic variation of properties with a quasi-period of around 1500 years. We say chaotic because these millennial shifts look like anything but regular oscillations. Rather, they look like rapid, decade-long transitions between cold and warm climates followed by long interludes in one of the two states.
Cherry picking the Quaternary? Very funny. The last 2.58 million are different because we entered into a period of extreme and rapid climate flucuation. This is the climate we have and not Miocene or something other.
Let me put it in a way an economist might understand. Warming not guaranteed. CO 2because it adds to climate instability. Economist ramblings absolutely meaningless.
Robert I Ellison,
I am well aware of the opinions like those you quoted from Woods Hole Oceanographic Institute. There are many thousands of equally scaremongering statements from all sorts of bodies and climate scientists.
You make derogatory comments about economics and economists. But it is the economists who do the cost benefit analyses of damages and proposed policies, and have most influence on policy making process. We cannot make rational policy decisions based on totally unquantified beliefs like you have quoted.
So I disagree with your comment:
I’d suggest the opposite is the case. I suggest you do not understand what information is required to inform rational policies. You clearly have little if any understanding about what “rational” means in relation to policy advice and policy decisions.
By the way, your responses to the three points demonstrated you didn’t understand them. That is why I repeated them and provided more background and references to help you to understand. It seems you still have not understood.
You have correctly stated that we are in a Coldhouse phase (only the third in the past 550 million years) and with that we get glacial-interglacial cycles and rapid climate changes (over years and decades). My point was that warming is not catastrophic. In fact, warming events are good. Furthermore, the climate is more stable when warmer. Yes, we may get another sudden little ice age in Europe, or other sudden climate changes this century. But there is no persuasive evidence to show that the proposed mitigation policies will increase the probability of better climate and reduce the probability of worse climate. On the other hand, the proposed mitigation policies will increase the probability of worse well-being, than would otherwise be the case, for a large proportion of the global population.
Warming the planet is reducing the risk and severity of cooling events. Sure you can try to argue that you know just how to control the climate, and we must stop releasing CO2 because we happen to live at the perfect climate now and you know it. “That’s laughable” (your words).
BTW I don’t advocate we keep emitting CO2. What I advocate is economically rational polices – something you clearly do not understand.
Please show the evidence that “CO2 adds to climate instability”?
BTW, I am not an economist, so tell the economists and the policy makers. I am sure they’ll take a lot of notice. Tell them about your long, meaningless, repetitive ramblings and I am sure they’ll drool over every word you say.
Suggestion: put your vitriol and silly ego in a box, and chuck it in a river.
Peter,
I will repeat my three points for your edification.
1. The damage function could be quite severe. Ireland with the climate of Lapland. Glaciers hundreds of metres deep across North America, global drought as evaporation slows to a trickle. This is a future seriously worth thinking about.
2. Climate sensitivity is regional and variable. This is not a question worth thinking about in terms of policy.
3. Decarbonisation as rapidly as is cost effective. We need to build richer and more resilient societies and to have cheap and abundant energy.
You have very little knowledge of science and technology. You leave long rambling and supercilious comments like some monomaniacal automaton. You never listen but have a information deficit model explicitly stated of educating the unwashed denizens. If you can lecture to everyone and inform their ignorance then the world will be better off in your own estimation. In the vernacular you are a legend in your own lunchtime.
So your silly umbrage and juvenile insults are of no account. I always find that the information deficit model leads to bad faith, arrogance and a deficit of civil communication. So what I suggest is that you take your 3 points, insert them and spin.
Cheers
Oh – evidence that Co2 destabilises climat? I don’t know Peter. Woods Hole not good for you? How about the NAS?
‘Abrupt climate changes were especially common when the climate system was being forced to change most rapidly. Thus, greenhouse warming and other human alterations of the earth system may increase the possibility of large, abrupt, and unwelcome regional or global climatic events. The abrupt changes of the past are not fully explained yet, and climate models typically underestimate the size, speed, and extent of those changes. Hence, future abrupt changes cannot be predicted with confidence, and climate surprises are to be expected.’
‘Abrupt climate change: inevitable surprises’ (2002) National Academy of Sciences Committee on Abrupt Climate Change, NAP
But it is all not an issue – Peter Lang says so.
Whatever Bastardi believes — that opinion alone should be accorded more than a 50-50 chance of being right.
Bastardi has yet to prove he knows anything at all about the long-term dynamics of sea ice. He’s better off sticking to short-term weather forecasts…
And, Al Gore?
Al Gore agrees
…agrees with China?
No, I don’t think Al Gore should stick to short-term weather forecasts.
Why would a lifetime liberal politician who was born to a life of privilege and has made millions peddling climate porn care about what you think?
One of the issues with bifurcations and external forcings is that we don’t expect a return to old stable attractors while the external forcing continues to perturb the system.
As the external forcing is in effect perturbing a new system, we expect more and different bifurcations, generally in the direction of the forcing if it is large enough.
The forcing — AGW — therefore could be said to be 100% responsible for changes that it has only a partial contribution to, because absent the perturbation we would expect a return to former states that we have not seen and do not anticipate.
Were PDO and AMO alone to be responsible for this shift — and we have seen ocean circulation shifts dramatically affect the Arctic before, in particular the shift that drove up temperatures in Svalbard about 100 years ago — it could become semi-permanent or stable. However, we’d also expect a balancing shift elsewhere that reflects the moving of heat from elsewhere by regional cooling of similar scale. Which we just don’t see. At all. ARGO says the oceans are getting warmer, not cooler; no region on order of the area of the Arctic reports an amount of new cooling on the scale of Arctic warming during the summers only. Natural variability holds no water. Not even with 15% ice cover.
The climate really does not care what man says or does. The Sun doesn’t care what humanity thinks, nor water vapor, cosmic rays the, mathematics of swirling vortices or even statistics. America and Western civilization is becoming increasingly irrelevant in world affairs because more and more of what is of concern in the West is irrelevant.
Wag said:
“The climate really does not care what man says or does.”
____
As the climate is not a conscious thing you are correct in this. But you can be sure that humans are very capable of altering the Earth’s climate.
I could be sure of that… if I knew more than Socrates.
BartR, “One of the issues with bifurcations and external forcings is that we don’t expect a return to old stable attractors while the external forcing continues to perturb the system.” We have no good clue how much the “external forcing” is perturbing the system.
http://i122.photobucket.com/albums/o252/captdallas2/climate%20stuff/internalthermaloscillations.png
Pinatubo perturbed things pretty well, only more in the northern hemisphere than the tropics and southern hemisphere. The 1998 El Nino, could likely be due to the Pinatubo perturbation. That chart shows the tropics response which is turning into a classic weakly dampened oscillation. The main source of energy in the oceans is and will continue to be the tropics and mid-latitude southern oceans. ARGO is not long enough to be conclusive, but even it shows the dampened response and less that expected 0-1000 meter warming.
Choice 3, looking at the longer potential oscillations looks pretty sexy, especially when you start with the southern ocean paleo reconstructions.
http://redneckphysics.blogspot.com/2012/09/the-best-place-to-start-is-at-beginning.html
Still a work in progress, but 45S to 65S is the main heat sink of the planet. From that, there has been fairly stable heat recovery from the early 1800s and there was a major perturbation around 1400AD. You can’t tell what “normal” is with only a few decades of reliable instrumental data.
There won’t be another “glacial” anytime soon with most of the land subject to glaciation being farmed, but there could be a hiccup in the thermohaline circulation should the Antarctic sea ice expand much more.
Capt’nDallas
Thank you for your redneck physics, a source for myown conformational bias.
I know this is presumptuous on my part, and you may already be on your way there: is there any hope of adding some regional cloud data, such as it is, to the mix?
BTW. If as a sailor you are not “faint of heart” you are either dead, or will soon be.
Rih008, I don’t do clouds. The migration of what I call the thermal equator would shift the tropical belt which would have a huge impact on cloud forcing, but without large amounts of land area to accumulate snow i doubt current changes would be anything like past changes. There has been some changes in cloud height in the tropics though. Costa Rican coffee plantains have had colder and wetter than normal conditions since the mid 90s and since the 1998 El Nino there has been some interesting issues with convection changes and tropical ozone depletion which may be related to the thermal equator migration.
http://www.mpimet.mpg.de/fileadmin/staff/stevensbjorn/Documents/StevensSchwartz2012.pdf
That is a good paper of the issues with clouds and soil moisture/temperature . Tony Masters has a new paper on cloud forcing which tends to dispute Dessler’s miraculous balloon velocity data for satellite skeptics :)
As far as deniers goes, the satellite skeptics are the ones that need to wake up and smell the technology.
Tom | September 18, 2012 at 10:45 am |
Huh. What about my conduct here suggests anything ‘professional’ about me in the least? And I gave up painting about the time I gave up looking for bogeymen in shadows. You should try that, as you don’t seem to have much shot at the ‘professional’ conduct thing, either.
captdallas2 0.8 +0.2 or -0.4 | September 18, 2012 at 12:56 pm |
I hope I haven’t mislead you into thinking I actually click on your links anymore.
One day I might, but it’d really require some indication you can handle the basics of the Science, the Math, the Statistics to a level I didn’t see last time I wasted my time looking.
Maybe take a course in some of those subjects at an accredited school online?
captdallas2 0.8 +0.2 or -0.4 | September 16, 2012 at 2:17 pm |
When I was five years old, I was enrolled in art classes. Theory at the time being if you introduce people too young to ideas they have no way to appreciate, you’re somehow giving them the gift of culture or some such.
My approach was to imitate the art that looked easiest. A single line of paint on the canvas. Splatters. Things like that. The issue was the class was being taught techniques of light and shadow. Which, being five, I had no real interest in. The only shadow in a five-year-old’s world has the approximate dimensions of an imaginary friend, or hiding place for a bogeyman.
Finally, the art teacher explained that I was attempting advanced techniques, and before I could do advanced art techniques, I had to first master the basics. He even showed me a folio of the works of the painters I was imitating, with their earlier paintings having a practically photographic quality of realism.
So I gotta draw on that lesson in this circumstance to advise, it appears you are attempting advanced techniques without the proper grounding or evidence you are competent to handle the basics. Your results look a bit childish, and seem to lack an appreciation of the underlying Science.
I must say Bart R, that you surprise me with your comment that you are a professional painter. I had no idea.
BartR,
I have no doubt it looks amateurish. What I am doing is exploring new methods. Working out the basic ranges of sensitivities is not that complicated, working out the variety of internal interactions and delays is the bitch. In order to put things into a more “normal” scientific perspective will require “tweaking” climate science a bit since they are clueless about approaches to non-linear, non-equilibrium problems and have developed a base set of assumptions inappropriate for the problem.
2889K at 396Wm-2 is irrelevant. The current average temperature and energy of 70% of the surface is 294.25K @ 425 Wm-2. The sensitivity to that reference to a doubling of CO2 is 0.4 to 1.0 degrees. That is pretty much a no brainer. If you start at the wrong point you get the wrong results. To roughly solve the problem you use a moist air and ocean model applying basic thermodynamics and compare that to a radiant model since the surface is the issue. Using a radiant model with an assumed surface at an estimated altitude with a range of initial conditions that vary by 2C degrees, is the crackpottery. I have moved beyond that into past climate which is more fun.
The Vostok ice core is not a representation of global climate. The oceans are the dog, Antarctic and the Arctic are the tails.
http://i122.photobucket.com/albums/o252/captdallas2/150kyeareventsignatureinthetropicaloceans.png
There are the tropical oceans, average range of variability is a little over 2C. That range is limited by the -1.9C salt water freezing point and 0C fresh water melt point. That is your range of natural variability. That is not rocket science either. Crack pots think Vostok teleconnects with global conditions or that some pine tree in Colorado tells the climate tail.
In 5 to 10 years all of that will be obvious and people that get paid to do the research will be forced to tell the tail. I am just playing with more interesting puzzles and enjoying be a touch cryptic.
BartR,
Since you are artistic, this chart is for you.
http://i122.photobucket.com/albums/o252/captdallas2/drawingoutsidethelines.png
The medieval warm period was a regional event, kinda looks like it is not all by its lonesome.
Now why would Antarctic CO2 not correlate as well to global temperature as it does to the regional temperature where it was collected? Could it be that fluctuations in the Antarctic Circumpolar current impact CO2 uptake?
I am sure that Webster has a Fickian explaination :)
With less old ice there was a qualitative regime shift to a less damped and thus HIGHER AMPLITUDE annual cycle after 2007, BUT THERE WAS NO BIFURCATION.
Livina, V.N.; & Lenton, T.M. (2012). A recent bifurcation in Arctic sea-ice cover.
http://arxiv.org/pdf/1204.5445v1.pdf
Regrettably, the authors SEVERELY (cannot be adequately stressed) misinterpreted the stats they calculated. I sincerely hope this is instantly intuitively obvious to every reader here upon reading sentence 1 of section 1 (“bifurcation detection”).
This is the most interesting thing that has come up in the climate discussion in many months. I hope there will be climate blog articles and university-course student-exercises focusing on this error because it is so painfully instructive about what can go hopelessly wrong with blind, TOTALLY COMMON-SENSELESS application of anomaly-think.
It’s almost unfathomable that authors of this methodological caliber could make such a mistake. Overlooking this is like failing to notice that a sine wave oscillates. It’s like never emerging from a lapse during which one is so thoroughly hypnotized (to the point of cognitive paralysis) by mindless pursuit of black-box computation that common sense awareness of the annual swing from summer to winter is TOTALLY suppressed. How this could happen to “climate experts” (and additionally make it all the way to publication) is a painful question to have to ask.
The lesson here for students is that rote application of statistical computing in the total absence of basic common sense can lead to EPIC misinterpretation. It’s sobering (to say the least) to see that the existence of the annual cycle (plain old summer vs. winter) was totally ignored by climate professionals during interpretation of algorithmic output. This error could be destined to become a classic climatology & time series analysis textbook example.
Wake up call:
Swings between 2 different states – NAMELY SUMMER & WINTER – were interpreted as NEW phenomena indicating climate instability.
This falls into the “wow – just wow” category of excruciatingly sobering blunders.
Ditlevsen (2012). Interactive comment on “A recent bifurcation in Arctic sea-ice cover” by V. N. Livina and T. M. Lenton. The Cryosphere Discussions 6, C1187-C1190.
http://www.the-cryosphere-discuss.net/6/C1187/2012/tcd-6-C1187-2012.pdf
Aslak Grinsted commented on Ditlevsen (2012) here:
http://judithcurry.com/2012/09/16/reflections-on-the-arctic-sea-ice-minimum-part-i/#comment-240690
There WAS a regime shift in 2007, but let’s not common-senselessly mischaracterize it.
Paul, I don’t know if you’re still reading this, but cannot “a change in the amplitude of the seasonal cycle” be the same as a “bifurcation” in this case?
BillC, the article could be reframed and the stats reinterpreted. I’ve offered to help.
Bart R
+1
Conservation of energy militates against the likelihood of a large internal variability component. Wiggles and wobbles we get. Trends we do not. Especially not trends in OHC.
So a long term trend in horizontal heat transport can’t change weather patterns or weather patterns don’t affect albedo or albedo doesn’t affect the energy budget? Which one is the one that breaks down the idea that heat transport can affect global temperature trends? Have citations? Don’t bother stating the law of the conservation of energy since that is only for closed systems.
Oh dear. Another ‘self-propelling climate’ nut. Internal variation is redistribution of energy and constrained by conservation of energy. It yields short (decadal) trends at most. Longer-term trends require a change in *forcing*.
I’m increasingly getting the feeling that ‘self-propelling climate’ nuttery is going to be the pseudo-sceptics next bastion of nonsense, once they are forced to concede the floor on ECS.
And please, no Demetrios. Please.
So was the YD event a forced change? What was the forcing? If it was internal was it longer than a decade?
Steven
The YD was, in essence, a feedback to orbital forcing: high latitude NH glacial meltwater turns off AMOC, equator to Arctic heat transport stops, NH gets cold *but* SH warms up.
The YD was *not* a massive global cooling event. See Shakun & Carlson (2010) for the fun details. In a nutshell, relative to the Holocene, GAT during the LGM was ~-4.9C. GAT during the YD was ~-0.6C.
Spatial reorganisation. Not self-propelling global climate change.
No, the YD was a different reaction to the same forcing caused by a change in heat transport. It is a clear difference from saying it was a change caused by forcing. As far as the SH goes why would anyone be suprised that it warmed? It didn’t have a change in heat transport and the entire world should have been warming had there not been that change. Did the SH go back into glaciation once the NH started warming back up? Of course not. It was not a simple redistribution of heat. It was a different reaction to the same amount of forcing based upon surface conditions.
No, the YD was a different reaction to the same forcing caused by a change in heat transport. It is a clear difference from saying it was a change caused by forcing.
Well, we can argue whether your ‘reaction to the same forcing] = my use of ‘feedback’ but I see little point.
However your next sentence *seems* to bring you closer to my point: the YD was an indirect response to Milankovitch forcing, which is why I classed it as a feedback.
All this is quibbling. The main point here is that the climate system is not self-propelling and people who claim otherwise have not understood the basics.
Again, quibbling. Internal conditions change, orbital forcing roughly constant during (relatively brief) duration of YD, global average temperature barely changes despite major albedo increase, YD ends, deglaciation continues apace…
No self-propelling climate there. We see the system acting under external forcing and concomitant feedbacks.
There is still a huge problem with the claim that it was energy redistribution and the difference was small. You don’t compare with a flat trend when the trend was obviously towards a warmer Earth. The only appropriate way to even begin to decide how much was due to energy redistribution is how much the SH cooled once the NH began to warm. You may be able to claim some small percentage was redistribution.
File:Epica-vostok-grip-40kyr.png – Wikipedia, the free encyclopedia
http://en.wikipedia.org/wiki/File:Epica-vostok-grip-40kyr.png
If the global average temperature during the YD was only about 0.6C cooler than the Holocene Altithermal (see Shakun & Carlson), then it’s hard to see how the cold NH/warm SH YD was anything *other* than an energy redistribution.
This seems to have run out of steam. Perhaps we can pick it up another time.
The Altithermal took place after YD not before. The cooling of the YD from a previous state, cooler than the Altithermal, was 0.6C.
Yes steven, I know that. As I said, this has run out of steam. Or put another way, you are engaging in contrarian waffle.
I’m not sure what I’m waffling about. Clearly the change in temperature was due to heat transport. Clearly it was more than 0.6C although I don’t see why this matters since one only has to show a single contradiction to prove an absolute statement to be incorrect. Clearly it was longer than a decade. But that’s fine we can end it.
steven
Apologies. Stuck gear. YD -0.6 relative to B/A:
If the global average temperature during the YD was only about 0.6C cooler than the
Holocene Altithermal(see Shakun & Carlson), then it’s hard to see how the cold NH/warm SH YD was anything *other* than an energy redistribution.steven
This is getting too tangled. The YD is not evidence of a self-propelling climate system. It was essentially a response to orbital forcing.
If you disagree with this, please explain how we got the YD *without* orbitally forced glacial termination. Please account for the halting of the AMOC without the glacial meltlwater flux at high NH latitude. Do you see what I am driving at?
BBD, “If you disagree with this, please explain how we got the YD *without* orbitally forced glacial termination. Please account for the halting of the AMOC without the glacial meltlwater flux at high NH latitude. Do you see what I am driving at?”
The AMOC has a beginning in the south and an end in the north. You are assuming melt water has more impact than it does. If the Drake passage is a diversion valve for the circumpolar current, then it would have a large impact on the AMOC. Go south young man :)
BBD, I understand your argument. It doesn’t change the fact that it was the change in heat transport that made the difference. If it were a case of merely warming up the glacial water that would be a completely different matter. A change in heat transport either can or can not change global temperatures. The YD hypothesis involving the shutting down of currents indicates it can. The appropriate question to ask is does heat transport have a long term trend, what is the cause of that trend if there is one, and if there is one what is the effect of that trend. The one thing that we should be able to agree on is that it does not have to equal out to no global change.
The AMOC can be turned off without stopping circulation south of the equator. But the SH warms up when the NH ‘heat pump’ is disabled. And it looks very much as though this is what happened during the YD, and earlier, in the first phase of orbitally forced deglaciation. See Shakun et al. (2012). Breaking science that should be of interest to you.
Apropos of southern polar warming, there may be quite a bit of carbon under the ice sheets: http://theidiottracker.blogspot.com/2012/09/the-antarctic-carbon-feedback-worst.html
We are a long way from knowing how much carbon is under there . . . this is just one study. And we don’t know under what circumstances it might come out. But if there is a tenth of the carbon and methane they think is down there, we need to prevent Antarctica from going the way of the Arctic.
How can altering heat transport force *global* change? Unless all the ocean currents started to act in concert and deliver either hot or cold water to the upper ocean layer?
BBD, by changing weather patterns thus changing the Earth’s albedo.
steven
This albedo change is *regional*. Unless all the various upwellings warm or cool simultaneously. And space sucks, as we know. For ever and always. You won’t get *global* climate change over long time scales.
BBD, even the paper you linked that concludes the YD was merely a redistribution of heat claims the 0.6C difference was most likely cause by increased albedo in the NH.
And I contend that it does unless we extend the scope of the discussion into geological time. If we restrict ourselves to a mere 700ka or so, we can say that earthquakes do not change the climate. Only external forcing can do that.
It is true that over geological timescales tectonics open and close ‘ocean gateways’ (eg Drake Passage, Tasmanian Gateway, Indonesian Gateway, Fram Strait, Central American Isthmus) and this has almost certainly altered climate over the Cenozoic (65Ma – present).
But what is *not true* is the belief that the climate system *now* is capable of internally-forced behaviour that explains modern observations. Above all, the rise in *global* OHC.
Ocean heat transport moves energy around within the climate system. It does not and cannot account for a generalised warming of the global ocean. That is a physical impossibility. Nor can slight changes in ocean heat transport alter *global* albedo sufficient to cause global OHC to increase. An external forcing is required.
Two things jump out at me here: you speak of ‘other scenarios’ and ‘possible heat transport trends’. My impression is that you think that ‘self-propelling’ climate ‘trends’ (something nebulous to do with changes in ocean heat transport occurring for no known reason) are an alternative explanation for modern warming. Alternative to increased forcing from CO2 and somehow missed by decades of intensive research.
I reject this position on the basis outlined above and upthread, and I urge you to do the same. It exists on the same level as perpetual motion machines: it is powered by energy from nowhere.
BBD, The oceans have settling times of 5,000 years indicated in the paleo data. The AMO versus Southern Oscilation indicates settling times of 15 decades. There is no forcing required for settling in an under dampened system.
http://redneckphysics.blogspot.com/2012/09/states-of-climate.html
Look at the bottom two graphs. The R states are used to compare to Selvam’s work.
http://redneckphysics.blogspot.com/2012/09/states-of-climate-ii.html
That would be the indication of shorter term oscillations that would vary dependent on the over climate state on a millennial scale.
Selvam has the theory in search of practical mechanisms. Wake up and smell the non-linearity.
BBD, you can reject anything you want. The fact is we have no data on long term heat transport so rejecting it or believing in it would both be an act of faith. I merely hold it out as a possibility.
BBD, we have been over how heat transport can affect albedo and even the paper you linked states it can yet you have gone back to stating some version of the conservation of energy law which only works in a closed system. I suspect we have reached an impass and I have no desire to have another CO2 conversation. I would point out, since you linked the OHC graph, that a very large amount was added in the ~2002 time frame. Do you have a physical mechanism in mind for that time frame on why so much heat was added from a persistent forcing in such a short period of time or do you, as I do, suspect this is a calibration error when switching to ARGO?
captdallas
Assertions, hand-waving, ‘black arts’ and home-made graphs. I’ll leave you to your fun. I don’t begrudge you your views, but do not expect to be taken seriously. No further comment.
Steven
I see we’ve hit the wall of denial. I can’t say I didn’t expect it, but I’m not pushing the rock any further up the endless hill. I will say that the exact point I gave up on you was when you tried to turn some uncertainty about the ARGO/XBT splice into an invalidation of the universally-accepted fact that global OHC is rising.
I know why you had to do that, and so do you, in your heart of hearts.
BBD, you have a jump in OHC roughly equal to halfof all of the OHC added since 1980 in one year and you don’t find that the least bit mysterious? Actually I don’t recall saying that OHC hasn’t been increasing. I also don’t recall saying that climate was self-propelled. I pointed out heat transport can affect the energy balance and I called into question why so much heat was added to the oceans in such a short period of time. Why you attribute more to what I say then what I actually say is a mystery to me so fill me in. Why did I have to do that?
Everybody agrees that the OHC reconstructions are a work in progress. Nobody disagrees that the global ocean heat content is *increasing*. Heat transport moves energy around the climate system. Why is the global ocean heat content increasing? If the energy was rising from the deeper ocean layers then they would be *cooling* but OHC in the deep ocean is also increasing.
Nor have you responded to my pointing out that changes in ocean heat transport cannot warm the global ocean. Instead, you chose to quibble about calibration errors instead of acknowledging the trend and its implications.
Please don’t be disingenuous.
Edging into a gallop:
[1] see above
[2] OHC is increasing, and changes in heat transport cannot warm the entire global ocean, see above
I didn’t attribute more to what you say than what you actually said. I disagree with what you do say and point to what you *don’t acknowledge*. Mystery dispelled.
BBD, simple question. If heat transport reduced the albedo of the Earth would the Earth’s oceans warm?
“Nor have you responded to my pointing out that changes in ocean heat transport cannot warm the global ocean. ”
You mean besides pointing out that the very paper you referenced says it can? How about because the models also say it can? You are the one in denial. The only question is is it not can it.
I’ve tried to focus on cause and effect, but we seem to have drifted away from this again. The question to answer is what would cause this change in ocean heat transport (OHT)?
The freshwater induced shutdown of the AMOC during the YD was caused by orbitally-forced melting of the NH ice sheet. A massive, even catastrophic geophysical event and certainly hard to miss if you were there.
So what is causing OHT to change now, 11.5ka into the Holocene? What are we missing?
The argument that this change it is somehow driven by energy reservoirs in the deep ocean is clearly flawed: the deep ocean would be *cooling* as it lost energy to the upper ocean, but deep ocean heat content is increasing at the same time as OHC in the upper ocean is increasing. How can this be?
Do you see the problems here?
I suppose if there has been no change in precipitation, evaporation, forcings, prevailing winds, fresh water contributions, and maybe some other things that aren’t coming to mind at the moment; we can expect that todays currents are exactly as they were 300 years ago.
Again with the conservation of energy argument. If it affects albedo does it require a net zero effect or not?
Stop dodging the questions and provide some answers please:
1/. What is causing OHT to change now, 11.5ka into the Holocene? What are we missing?
2/. The argument that this change it is somehow driven by energy reservoirs in the deep ocean is clearly flawed: the deep ocean would be *cooling* as it lost energy to the upper ocean, but deep ocean heat content is increasing at the same time as OHC in the upper ocean is increasing. How can this be?
You must be able to answer these fundamental questions or your hypothesis fails.
You have me confused with someone else. I have been arguing albedo not deep oceans. You have yet to answer my simple question about albedo choosing instead to ignore it and ramble on about energy conservation. Also if I knew what was changing the currents I would know something is and hey, maybe they’d name a post office after me or something. I gave a partial list of things that could. My points stand, heat transport can change the energy budget and we don’t know if there has been a long term trend in heat transport. I am pretty much done with arguing with you. You are confused and getting an attitude.
You are arguing that an imaginary change in the global ocean circulation (aka THC) is reducing global albedo. How could it do this? By warming the upper ocean (agrees with observations) and reducing low cloud cover (unclear from observations: ISCCP data are routinely over-interpreted/downright misrepresented on this point).
Now, how could an energy transfer from deep water to the upper ocean layer happen without *cooling* the deep ocean?
And you think I’m the one that is confused.
It is clear that you don’t understand this topic. You don’t grasp that changing global albedo requires energy from the deep ocean which *must* cool as a result of losing energy to the upper ocean. Instead you retreat into the self-propelling climate error – and deny that this is what you believe. Which makes bad quite a lot worse, in my book.
You mistake my mild exasperation at being unable to get you to think your own argument through objectively as ‘an attitude’.
Ultimately, you *cannot* dodge this question:
How can the upper ocean be warmed by an energy transfer from the deep ocean if the OHC of both layers is *increasing simultaneously*.
If you cannot answer this question, your hypothesis fails.
So you have decided it has to be from the deep ocean and then attribute this hypothesis to me and tell me I have to defend it? How very kind of you but I’d prefer not to have your help in the future.
“So this structure could be due either to the response to other forcing agents, aerosols in particular, or to internal variability. The major source of internal variability on these time scales is thought to be the pole-to-pole overturning circulation in the Atlantic ocean. Variations in the strength of this circulation alter the temperature difference between the hemispheres. In models, the mean NH temperature is a lot more responsive than the SH to this variability, so a stronger than average overturning warms the NH more than it cools the SH, resulting in a global mean warming and providing a consistent picture for the relatively steady SH trend.”
That’s from Isaac Held. Now explain why this has to be from the deep oceans or why it wouldn’t affect albedo. Next time keep your hypotheses to yourself. I am not responsible for them.
Steven
It’s funny how popular Held’s #27 has been with contrarians recently ;-)
Even so, I’m not sure why you introduce it here. Held argues that decadal wiggles from internal variability complicate the estimation of TCR to GHG forcing. Held *does not* argue that recent temperature trends can be explained by natural variability, including ocean circulation.
BBD, Held argues that a change in heat transport makes an overall change to the temperature of the Earth. Just because he is commenting on a shorter period of time makes this not true for a longer period of time why exactly?
Natural variability is self-cancelling over multi-decadal timescales. The climate system wobbles, but does not trend unless *externally forced*. This is basic, introductory climatology. Held knows this. I know this. Climatologists know this. Only you disagree.
You will find this article by Kyle Swanson at RC informative and helpful in dispelling confusion.
You will also be interested in Huber & Knutti (2011) Anthropogenic and natural warming inferred from changes in Earth’s energy balance. From the abstract:
How long are you going to keep this up before you admit that you are mistaken and confused?
BBD, It appears you have conceded that heat transport can change the energy budget and your argument now is that this is limited to short time frames. Is this correct? I’d just like to close one chapter before we bother starting a new one.
You nailed it BBD.
This is the fake skeptics current bit of Kryptonite.
They want to believe that this natural variability is the key and so they all unisonly chime in, spread across multiple threads.
But the Kryptonite comes in when all you have to ask them is where does the warming come from? And will you please describe a toy model of the process?
Silence ensues.
I ‘concede’ nothing. I started out saying that the climate system is not self-propelling and I’m still saying it. Have you read the supporting references provided above? Do you finally understand that internal variability cancels out over longer time scales? That it doesn’t drive trends because moving energy around within the climate system is not the same as adding energy *to* the climate system (see also WHT’s comment). Do you understand this yet?
BBD, of course you concede nothing. Despite the fact that both the models and the YD hypothesis indicate changes in heat transport can affect the global temperature, and in the case of the YD so dramatically temperatures go against the forcing trend, you are steadfast in your beliefs that it is impossible that any long term trend in heat transport can be affecting modern climate. You have as your support your assertion that this is impossible. I say we don’t know. You see in order to know that you would have to have a very clear understanding of what drives heat transport. So you have a very clear understanding of what drives heat transport? It seems to me I have recently seen a paper that declares changes in the currents of molten lava may affect currents. I noticed WUWT referenced a paper that states stratospheric currents may affect heat transport. We already knew fresh water addition or subtraction can affect currents. Is dam construction a forcing? How about irrigation? Speaking of irrigation does that cause a change in heat transport separate from ocean currents? Has there been a trend in irrigation? What about changes in the hydrologic cycle? Does irrigation and dam construction affect that? How long does it take for a current to come to equilibrium with a forcing? The YD event lasted a long time indicating a long time for the current to reorganize. Are we experiencing a long term adjustment to heat transport from an earlier forcing? Of course not because you assert we aren’t. I’m sorry but science by assertion is not convincing and that includes assertions where you have a cheering section.
The YD was just ~0.6C cooler *globally* than the Bølling-Allerød. Given the huge climate change in the NH, the net effect is trivial and fully supports the contention that minor changes in OHT do not cause long term synchronous *global* warming or cooling because they are just *reorganisations* of the way energy moves around *inside* the climate system. You simply cannot draw a line from the YD via Held to this discussion in the way you think you can. That you try is very clear evidence that you don’t understand the basics. Misrepresenting Held was particularly obvious in that respect. You shouldn’t have done that. Held *does not* argue that recent temperature trends can be explained by natural variability, including ocean circulation. He knows better than that.
I’m simply pointing to standard climatology and the scientific consensus. And even when I offer specifics you ignore them – eg Huber & Knutti. Read the words instead of coming back yet again, and being insistently, stubbornly *wrong*: internal variability averages out over time; it is not demonstrably responsible for modern warming trends. Read.
I say you don’t understand the basics, you are deliberately ignoring references, you won’t admit that you have conflated energy *transport* within the climate system and energy *accumulation* within the climate system and you don’t understand the importance of time scales in this discussion. And to top it all off, you are referencing… WTFUWT.
As for your quip about science by assertion, what exactly have you been doing for the entirity of this thread? Assertion after assertion, not a single reference in sight, serenely confident that you know better than everyone else…
This is now getting actively tedious. I thought you were genuinely interested in understanding this topic better. It is now very clear that you are fundamentally concerned with bolstering your prior commitment to the denial of the dominant role of CO2 forcing in modern climate change.
It is tedious to argue with someone that doesn’t understand supporting a concept..
Actually I’m not letting you off that easy. Show me where I said Held stated there was a long term trend in heat transport. If you can I will make an appropriate apology. If you can’t this conversation is over. I am rather tired of you insisting I defend things I never said.
Stop being so blatantly disingenuous. You selectively quoted from Held to give the impression that he supported your view that climate is self-propelling and Held does no such thing. You were just unlucky that I am familiar with Held’s blog. And now you are getting even more tiresome by retreating into disingenuity and nit-picking instead of facing up to the fact that you are *wrong* and have been comprehensively show to be so.
So you can’t show where I have said Held states there has been a long term trend in heat transport to support the self-propelling climate I never claimed was self-propelling from the transfer of heat from the deep oceans that I never claimed was transfered. Time to end this conversation.
When someone who has been arguing for a self-propelling climate system for dozens of comments starts claiming (again!) that they weren’t, the exchange is indeed over. You are pushing disingenuity to the border of dishonesty. It is contemptible.
If I have I would admit it since I have no problem with anything I have said. I suspect the only problem is with your comprehension and my integrity is not directly proportional to your level of comprehension. On the other hand I am not familiar with the hypothesis of self-propelling climates so maybe there is a connection that defies the name. Where can I find this hypothesis of a self-propelling climate and show me exactly what I said that would place my argument in this category. This isn’t going to be another one of your blunders is it? Calling me dishonest seems a bit much from someone that hasn’t been right about anything so far.
There is no problem with my comprehension.
- You propose a *trend* in ocean heat transport (not sure really what this means except that it’s an imaginary change that heats up the upper ocean and the troposphere)
- You cannot provide any mechanism, just waffle
- Waffle-driven imaginary trends and magic energy increases in the climate system are the very essence of the self-propelling climate fallacy
And you still think you understand this topic.
The very essence of. Ok. Whatever.
Ouch. You just know this is just going to hurt.
http://www.ldeo.columbia.edu/~jsmerdon/papers/2012_jclim_karnauskasetal.pdf
Feel the burn.
=========
That’s it? That’s your counter-case? A single, modelled study? ;-)
Since you still haven’t quite got the point yet, as your last link eloquently demonstrates, here again is a reminder that we are discussing *global energy imbalance*, not equatorial Pacific SSTs.
You need to explain to yourself – not to me – why global OHC is rising.
You need to ask yourself why is an enormous amount of energy accumulating in the global ocean?
You need to ask yourself why this is happening *now*, at exactly the same time as the effects of increased GHG forcing are expected to become increasingly manifest.
You need to ask yourself what happened to the painstakingly calculated forcing from GHGs?
You need to ask yourself where in the climate system is the most likely place for all that energy to accumulate?
You need to ask yourself whether, in the light of these questions, the most likely explanation for global OHC increase is ‘natural variability’ or increasing GHG forcing.
In summary, you need to ask yourself why you going to absurd lengths to avoid parsimonious reasoning.
No, are you ever anything but wrong? My case is a collection of scientists that don’t know if a model output is being caused by the model or by heat transport. They obviously forgot to ask you because you would have told them one possibility is impossible. Just for your information I suspect model output is in error and that accounts for a great portion if not all of the modeled cycle since it sems difficult to believe that a cycle of that magnitude would not have been picked up before a model showed it was there but I can’t say for sure it isn’t as shown. The point is you have been saying it is impossible. Experts don’t know it is impossible. They are as clueless as I am. You must write them ASAP and inform them, the reviewers, and the publisher that they are idiots and liars, believe in a self propelling system, and need to go learn some basic physics. Please share the response to your letter.
BBD, the most likely cause. Because there can only be one. Thank you Highlander but my view of the world may be more complicated than yours.
I see where you have made yet another mistake. Just go read the summary and see if you can figure it out for yourself.
Stop ignoring the important questions. You are behaving like a denier. Are you a denier? If not, why don’t you address the questions?
Why are you going to such absurd lengths to avoid parsimonious reasoning?
Again:
1/ Why is global OHC rising?
2/ Why is an enormous amount of energy accumulating in the global ocean?
3/ Why is this happening *now*, at exactly the same time as the effects of increased GHG forcing are expected to become increasingly manifest?
4/ What happened to the painstakingly calculated forcing from GHGs?
5/ Where in the climate system is the most likely place for all that energy to accumulate?
6/ In the light of these questions, is the most likely explanation for global OHC increase ‘natural variability’ or increasing GHG forcing?
No more editorialising guff please. Just answer the questions.
Now you know.
A video clip? Well, yes, now I know. You cannot answer the important questions because you won’t employ parsimonious reasoning because you are a denier.
Phew. Got there at a last.
Yes. Caused by ice formation resulting from a change in heat transport triggered by meltwater flux at high NH latitude initiated by orbital forcing ;-)
We can keep this up until the next glacial, but the YD is not evidence for a ‘self-propelling’ climate system. Please, in the interest of rational discussion, concede the point.
Do I have the honour of addressing Mr S. Mosher?
If a huge earthquake had caused glaciers to drop into the ocean and that had shut off the current would that have the same effect? I contend it doesn’t matter what caused the change. It matters what the change was and the effects after in order to apply it to other scenarios such as possible heat transport trends. But we can agree to disagree if we begin to retread our ground. No, I am the unknown steven. I drill holes in teeth not trees or ice.
steven – response misthreaded – see above.
BBD, over what time period are you considering conservation of energy? Think about the 1945 drop in ocean temperature. That started in the southern hemisphere with no known volcanic “trigger”. The northern hemisphere sulfate explanation is weak at best if you look at the origin of the “event” which was likely just a prolonged la nina or negative ENSO phase. The oceans contain a 1000 times the energy of the atmosphere. A minor deep ocean burp, spells cooling with a long recharge time.
http://redneckphysics.blogspot.com/2012/09/super-duper-la-nina.html
A simple major natural variability scenario that conserves energy with a pretty dramatic climate impact. You guys are eons from figuring out climate.
IIRC I did say ‘decadal’ and perhaps I should have said ‘a couple of decades at most’.
A coupla decades 15 decades, what is a century among friends :)
How can altering heat transport force *global* change? Unless all the ocean currents started to act in concert and deliver either hot or cold water to the upper ocean layer?
Compare these two transistions from glacial,
http://i122.photobucket.com/albums/o252/captdallas2/WesternCaribbeanCO2EPacificandmilankovicwithlightsmoothing125to200kyear_zps546bfd1f.png
E. Pacific leads exit.
http://i122.photobucket.com/albums/o252/captdallas2/WesternCaribbeanCO2EPacificandmilankovicwithlightsmoothing40kyear_zps6d9c3d29.png
The more uniform exit from the last glacial maximum.
I would think an E. Pacific lead more likely due to Antarctic events and the more uniform Arctic or pure solar driven. Depending on which leads the exit from glacial, the time constants for deep ocean warming would be different. The upper ocean mixing layer drives “climate” and the deep ocean determines the time constants. The differences really boil down to the efficiency of mixing ocean layers.
Positive feedback is more than “trendology”, which looks like a dismissive term. It was a predicted consequence of ice-albedo reduction that the water would get warmer making it harder to freeze in each successive year. While AGW predicted this decline (perhaps not so fast), the other so-called theories have no predictive value and are therefore not even testable. Arctic Ocean temperatures are 4 degrees warmer than climatology in some areas this year. To say this is a natural fluctuation is a bit of a stretch.
BTW, WUWT has a new article about the next ice age today. I think this is designed to soothe the frayed nerves over there about this whole Arctic sea-ice thing. It must be very upsetting to their whole creed.
Please…David Archibald hasn’t changed his beliefs much in years.
Take a look in the comments…the debate between Lief Svalgard and David Archibald is as vigorous as ever.
Southern Hemisphere Sea Ice is another subject of course…growing…growing…and growing..
I’ll quote Isaac Held
http://www.gfdl.noaa.gov/blog/isaac-held/2012/04/30/27-estimating-tcr-from-recent-warming/#comment-588
How plausible is it that well-mixed greenhouse gases in isolation could have forced the very different warming trends in the NH and SH over the past 30 years? Shouldn’t we expect WMGG-forced warming to be larger in the NH? Yes, but a factor of 2? I have assumed that this is implausible
It is positive feedback, not only from summer ice area, but also from winter snow area over the northern continents. The SH has neither of these effects due to lack of polar water and high-latitude sub-polar continents.
I think if f they chained one section of Antarctic sea Ice tightly to the coastline, Its extent would stop growing.
Isaac is super smart and should know better, especially in light of the data showing the high level of warm water entering the Arctic ocean that really wasn’t part of most climate models on this scale. No such mechanism exists for this kind of energy transport to the middle of the land mass that is the South Pole. You’ve got a 2 mile thick slab of ice sitting on a land mass that is tough for any outside energy from atmosphere (and certainly not ocean) to penetrate. By comparison, the Arctic is fairly easy for energy to flow into via atmosphere and ocean.
And if you look at the paleo data, you find that not only to the poles warm in excess of what the models predict, in recent geologic ages you can see a North-then-South pattern, presumably due to 1. Arctic warming 2. Weakening/disruption of the THC 3. More warm water to the South.
Models are great, but we can also see things in the paleo record that are not reflected well in the models but are reflected in changes we see in the climate today. And the degree of polar amplification is a prime example of that.
http://i122.photobucket.com/albums/o252/captdallas2/climate%20stuff/milankovicandTropicalSST.png
I saw that, poor guys got it all wrong. I keep saying to follow the energy but no one listens. Anywho, the Milankovic Cycles appear to have been adequately defended.
The funny part is that the Solar prolonged minimum will have greater impact that “modeled” because the premise of “sensitivity” to all forcing is incorrect. Never hire an astrophysicist to do an engineer’s job.
I think we are looking at something like this:-
@ Prof. Curry…
Does your preference for Hypothesis III mean you’re softening your skepticism of “tippiing points” a la Hansen?
BTW, the link in your “Pondering” post is broken. Here’s one that works (at the moment): polyak et al. (2010)
It is quite possible that warming assisted by CO2 is responsible for the rapid ice melts. There have been a few unusual weather patterns/events that have helped though.
On the other hand, there are news reports from the 1930′s and as I recall the 1890′s?? that talk about similar events occurring over several years and with similar sounding alarmism. (news people have been doing this a long time as it’s how they increase sales).
SInce there is a 60 year cycle in many natural weather patterns and since the satellite coverage of ice (and hurricanes for that matter) has only been going on for about 30 years (and during a cool period), it kind of makes sense to wait 10-15 years before wetting ourselves.
See my post above (the first) for a link to many such newspaper articles. The ice melt seems to be a cyclical event (as per the Greenland one, but more frequent).
Whatever we observe – it has happened before.
What I would like to know re AGW is – WHAT is the optimal global temperature (actually, what meaning IS there in a “global temperature” anyway?) and how do we know that it is optimal?
(FYI – I am a total lay person in climate matters, but fascinated and slowly educating myself).
To understand this, consider one impact of warming — sea level. What is the optimal sea level? Could it be 10m or 25m or 50m higher than today?
What do you think?
Dear all
I am currently working on my article ‘Historic variations in arctic ice- part two.’ It is a long job as it involves ploughing through hundreds of research papers (many very dull-Mann and Hansen tend to write the most interesting papers-and Judith of course) ,visiting the Met office archives and will need a journey to the Scott insitute in Cambridge.
To put down a framework I am trying to get some fixed points of ice extent and wondered if anyone had come across any research paperts on Arctic ice extent during;
1) ‘ The Viking period’ which we shall call roughly 850 to 1250AD i.e the Viking colonisation of Greenland and their journeys to Newfoundland.
2) Arctic ice extent during the last great melting period from 1918 to 1939.
Thanks for any help. In the meantime Denizens might be interested in this curious Pathe News film of how the dastardly Americans intended to change the flow of the Gulf stream in 1936 in order to warm themselves whilst plunging Britain into an icy chaos.
http://www.britishpathe.com/video/gambling-with-gulf-stream-aka-gambling-on-the-gulf
I will commemt on Judiths post separately
tonyb
I very much look forward to that paper Tony.
Tony. I hope you have a copy of “The Little Ice Age”, by Jean Grove. Mine is the 1st edition, a second edition was published some time ago.
Chapter 2 is Icelandic glaciers and sea ice. She shows a figure (2.7) “Monthly sea ice positions around Iceland in the periods 1886-92 and 1965-71.” It is after Sigtryggsson 1972. “An outline of sea ice conditions in the vicinity of Iceland”, Jokull 22: 1-11.
Hector
Thanks, useful suggestion, Jean Grove was an excellent researcher, I will reread that Chapter. Lamb also has some good material. There is no shortage of references, the great problem is sorting the wheat from the huge amount of chaff!-much of it tedious- and putting it into area and chronological order!
Tonyb
Came across this some time ago, it may have a snippet of info missed elsewhere
http://ipo.npolar.no/reports/archive/iapo_inf_03.pdf
you can start at p.4
Thanks Vuk
Tonyb
Hi Tony,
I will be visiting the SPRI next week and meeting the head of the outfit prof Julin Dowdeswell for a couple of hours. If you let me have a list of stuff you need I can try to get it organised in advance for pickup.
“Reconstructed changes in Arctic sea ice over the past 1,450 years”
http://www.nature.com/nature/journal/v479/n7374/full/nature10581.html
I dislike intensely a discussion of Arctic sea ice in isolation. I cannot see how we can have a rational discussion unless we discuss Antarctic sea ice at the same time. I cannot see why the Arctic is peculiar. Are we viewing a purely regional effect? Surely, what affects the Arctic ought to also affect the Antarctic. If not, why not.
Jim Crispwell said:
“I dislike intensely a discussion of Arctic sea ice in isolation. I cannot see how we can have a rational discussion unless we discuss Antarctic sea ice at the same time.”
___
You probably need to do a little more study then Jim so you can understand how the Northern Hemisphere and Southern Hemisphere sea ice are subject to very different dynamics. Really.
One is on land the other on the ocean. It makes a difference. If you are this ignorant about it, you need not comment at all
Many of us are on a learning curve. That was a reasonable question, especially as there seems to be some inverse relation between the ice at both poles. No need to be rude is there?
A reasonable question wouldn’t begin ‘I intensely dislike.’
I erred in not noticing that you were talking about Antarctic SEA ice; sorry about that.
However, the differences between the Arctic and Antarctica are striking and important. The Arctic melting is having profound effects on global climate, as there will be more heat-absorbing ocean instead of heat-reflecting ice there in the summer. And the changes there are likely to give Europe another horrible winter:
http://www.wired.com/wiredscience/2012/09/sea-ice-extreme-winter/
http://www.guardian.co.uk/environment/2012/sep/14/arctic-sea-ice-harsh-winter-europe
http://www.bbc.co.uk/news/science-environment-17143269
The Arctic has an ocean flowing through it. The Antarctic has an ocean flowing around it. The Northern Hemisphere has the most land. The Arctic controls the temperature of Earth. The Antarctic does help with this and there is a phase shift. The ocean currents do link the north and south.
It does snow more when oceans are warm and it does snow less when oceans are cold. This is true in the north and in the south. I have talked about the north above so I will say a few words about the south. When oceans are cold the snow falls on ice shelves in the Antarctic and the snow does melt in summer. When oceans are warn there is less ice around the Antarctic and the snow does fall on land and does not melt in summer. The Antarctic does get snow added on top and lost at the sides. This has been in good balance for ten thousand years or the ice core data would show something different.
To my critics. I am fully aware that there are differences between the Arctic and Antarci sea ice conditions. I have studied the issue in some considerable depth. Of course, there are major differences between ice formation at the two different poles. That is not the issue.
The issue is how much influence does adding CO2 to the atmopshere make to both poles at the same time. Is there some mechanism whereby because the ice conditions are different at the two poles, therefore CAGW has a different effect in the Arctic as opposed to the Antarctic? Is someone suggesting that because the ice conditions are different at the two poles, therefore the effect of CAGW is different at the two poles? And if si why?
I recommend you read a book, and not expect internet commenters to do your work for you. If you want to learn something, do it. If you currently can’t imagine how CO2 could affect north and south poles differently, that’s known as a ‘you’ problem. This topic has been beaten to death in the past – do a little work.
MarkB
You are clearly new to internet blogging, so let me help. Here it is perfectly reasonable for people to confess ignorance and/or ask for explanations. And thus it is entirely inappropriate and uncouth to tell people to just go away and read “a book” (you don’t even know one to suggest?) Especially on the back of the spectacularly dumb/arrogant argument that the science here is settled.
You need to go and read the science websites: try here:
“The Arctic ice cover plays an important role in maintaining the Earth’s temperature—the shiny white ice reflects light and heat that the ocean would otherwise absorb, keeping the Northern Hemisphere cool.”
“Even if wintertime Antarctic sea ice were to increase or decrease significantly in the future, it would not have a huge impact on the climate system. During the Antarctic winter, energy from the sun is at its weakest point; its ability or inability to reflect the sun’s energy back into space has little effect on regulating the planet’s temperature.”
http://nsidc.org/icelights/arctic-sea-ice/
http://nsidc.org/cryosphere/climate-change.html
You are not going to learn a lot by relying on denier blogs – you have to go to the science ones. And if you are one of the many people here who assume that scientists are corrupt and dishonest, you are not going to learn much.
I’m tired of saying this in every thread, but boy, does it need to be said.
+1
Being an ocean, the Arctic ice is a much less stable system because it is subject to positive feedback from the albedo change, while the Antarctic albedo can stay quite fixed, so it is not going to have this positive feedback.
Once the Arctic goes, the albedo change affects the whole earth, so everyone warms up. Next Greenland would go, with a further increase in albedo and sea-level, then Antarctica with a final sea-level rise of 70 m. This is basically the reversing of their formation sequence between 35 and 10 million years ago, but in the space of a few centuries. At CO2 levels above 500 ppm, even the continental ice sheets are not stable systems, but we are not there yet.
I’m afraid you’re wrong again. Antarctic SEA ICE (yes Virginia, that’s *floating* ice) extent is a bit greater than Arctic sea ice. In 1979 they were both identical in average annual extent at 12.5 million square kilometers but since then Antarctic has increased a hair and Arctic has decreased a bit over 1 million square kilometers.
http://www.climate4you.com/images/NSIDC%20GlobalArcticAntarctic%20SeaIceArea.gif
Does it bother you at all that you make so many errors of fact? I mean everyone should be entitled to an opinion, stupid as it may be, they they shouldn’t be entitled to their own facts.
“Does it bother you at all that you make so many errors of fact?”
It’s nice to see you taking an interest in factual errors. Unfortunately you don’t seem to have found any. But the thought counts for something!
JimD, “This is basically the reversing of their formation sequence between 35 and 10 million years ago, but in the space of a few centuries. ” WTF?
The Drake passage opened up about 40 million years ago when SA separated from Antarctic. The circumpolar current gradually increased which increased the rate of heat loss at the south pole. The increased rate of Antarctic sea ice would reduce the efficient of the circumpolar heat exchange which would change the thermohaline current, but with the depth of the Drake passage and an estimate total flow of 80 million cubic meters per second, I doubt that will stop abruptly.
Here JimD, about 3.5 million years of tropical sea surface temperatures.
http://i122.photobucket.com/albums/o252/captdallas2/climate%20stuff/35millionyearsofsst.png
That is rather long term cooling trend.
Arctic Ice Melt Could Mean More Extreme Winters For U.S. And Europe
http://www.huffingtonpost.com/2012/09/12/arctic-ice-melt-extreme-weather_n_1878833.html?ncid=edlinkusaolp00000009
The warmer Arctic and the colder more extreme snows in the mid-latitudes is exactly what is happening. That is Ewing and Donn Climate Theory. The snow that cools earth does fall in the mid-latitudes and around the arctic. The snow that does fall in the mid-latitudes and between the arctic and the mid-latitudes does make a difference. There was a lot of ice in mid-latitudes during the little ice age. The snow that caused the little ice age fell when the arctic was open during the Medieval Warm Period. That is what caused the little ice age. It snows when it is warm and that causes cold. Consensus Climate Theory uses junk science to make it cold and then they create snow while water is already frozen and there is no source for snow. The snow falls when the arctic is warm, it piles up at the heads of glaciers while the tails of glaciers are still retreating. It advances later and makes it appear that ice volume is increasing later. Watch the snow that will fall soon
Earth is warm and the tails of glaciers are still retreating and land temperatures will still go up in summer. The arctic is open and the snows are falling and the winters have more snow and cold. Ice volume is building and after this typical period, similar to the Medieval Warm Period or Roman Warm Period, the ice will advance and cool the earth, land and ocean and the earth will go into the next cool period, similar to the little ice age. Then the arctic will freeze and turn off the source for moisture and the extra snow will stop. Look at the history because the history is the future.
The arctic is not warm because the ice has melted. The ice melted because warm ocean water melted the ice and allowed the arctic to get warmer. The warm oceans and open arctic will keep the snow falling until there is enough ice volume to cause the next cool period. It snows when the arctic is open and it doesn’t snow when the arctic is closed.
This does keep the temperature of Earth well bounded and it is this simple.
It does not matter what anyone’s calculations say. It only matters what happens.
When the oceans are warm and the arctic is open it snows as much as necessary, where ever it is necessary to turn the temperature down.
When the oceans are cold and the arctic is closed it snows less and the ice retreats where ever it needs to allow the earth to warm.
It is this simple. Look at past data and the new data as it becomes available
IIt is this simple
IT IS THIS SIMPLE!
Temperature has been bounded within plus and minus one degree for most of the past ten thousand years. Temperature has been bounded within plus and minus two degrees for all of the past ten thousand years.
It snows more when the arctic is open and it snows less when the arctic is closed.
The temperature that arctic sea ice melts and freezes is the set point for earth temperature.
If you disagree, please offer your own idea of how this was accomplished.
Do not consider powerful control with well enforced limits with a trace of anything? Or, go ahead.
II. Climate shifts hypothesis:
s/b
III. Climate shifts hypothesis:
oops thx
??? That seems to cover a lot of bases.
Judith – how have you quantified the uncertainties in that statement? What is your confidence interval w/r/t your >66% likelihood? Is this based on empirical data/observations? Modeling or historical records? Is it a seat of your pants guesstimate? How did you reach your measurements of likely levels of “natural” forcings?
I determined my uncertainties in the statement by the same standards used by the IPCC.
Judith
Don’t you consider those standards. sub-standard? Shouldn’t you use engineering-quality methodologies?
Nope, I sink to their levels on blog posts
As long as Judith doesn’t sink to your level Josh – the discussion remains credible.
I’m beginning to wonder when was the last time that Judith met a standard she didn’t double.
On the one hand, she applauds blog discourse as a valuable contribution to scientific analysis from an “extended peer review community.”
On the other hand, she discounts blog discourse as not worthy of a standard above one she considers to be sub-standard.
Chief –
Just out of curiosity – what about my comments on this blog = a level that she doesn’t sink to? Could you point to few examples of cases in point – for my edification?
Given that you seem to think that writing long diatribes filled with insults is a standard worth reaching for, I’m wondering about what metric you use for measurement.
Joshua,
You need to be a little more discriminating. Especially where there are responses to your obvious sarcasm involved. You may then try to make a schoolboy debating point out a remark made in the informality of the blogosphere.
The comment was to the effect the standard used was that of the IPCC. I see your point that this diminishes the standards of the blogosphere. But I am a little busy discussing Arctic science to rehearse the foibles of a pointless little troll.
I do tend to distinguish the scientific interests from responses to the rude and noxious – but I can be fairly inventive in responses to vicious trolls who drop in with content less and insulting drivel. Frankly – I am a little borred with it and would prefer to have civil and productive discourse. Feel free to peruse my posts elsewhere on this thread and explore the links. This would be a better use of your time than the ongoing niggling at the some inconsequential and misplaced point. So you will forgive me if I move on now.
Cheers
Joshua
You’re being confused by your own increasingly motivated reasoning. CE standards are below (proper) journal article level, but (easily) as rigorous as anything the IPCC does or uses.
Intersting Joshua…
to paraphrase:
JC: IPCC standards are too low, and should be better!
JC: I am using IPCC standards
Joshua: Those standards aren’t good enough!
Heh – I hope you communicated your disppointment with IPCC standards to the IPCC itself, and are not using some rhetorical tricks in a lame attempt to pillory our host… although hstory might tend to indicate the opposite, I wil give you the benfit of the doubt in this case. Care to clarify?
I still find it interesting that all these so called effects of AGW is caused by 2.5% of C02. If that minuscule amount has the potential for all the perceived changes in climate, then should not the other 97.5% have done us in by now.
It is always mentioned here and there the rise of C02, are we talking the 2.5%, or the 97.5%. To me that is hardly ever broken down in discussions, but the use of 100% keeps the money flowing I suppose. What is causing the 97.5% rise? oceans? sun?
What was the ebb and flow of arctic ice in the thirties?
South pole hit a record recorded low this winter.
Not sure what 2.5% you mean. Current CO2 levels are 40% higher than preindustrial, and twice those in ice ages. They could yet double again by the end of the century.
Ha ha, she owned Joshua……twice!
(That comment was not aimed at you, Jim D)
pwned
When in Rome… use the lingua franca.
“I determined my uncertainties in the statement by the same standards used by the IPCC.” A clever, barbed, answer by JC, implying (I presume) that the IPCC uncertainty standards have little meaning.
The problem is that we are left wondering what JC’s view actually is – by indulguing in snark at the IPCC she undermines the reader’s understanding ofwhat is supposed to be a serious piece.
This may be of some interest.
A warmer Arctic Ocean during ice age times
http://www.geo.su.se/index.php/news/544-a-warmer-arctic-ocean-during-ice-age-times
“Based on their results, the researchers conclude that the Arctic Ocean has a previously unrecognized high sensitivity to changes of the freshwater input over multiple timescales, which is manifested in large temperature excursions of the intermediate water layers.”
John from CA
The Cronin study is indeed interesting, but has no obvious relevance to what is happening now:
There was an interesting study done in 2007 that pointed to increased salinity of Pacific ocean water entering the Arctic via the Bering Strait as the cause of nearly 50% of the melt. Extreme storm circulations also played a role in flushing the ice.
Have you run across any info for 2012 Arctic salinity readings?
NASA Finds Russian Runoff Freshening Canadian Arctic
http://www.nasa.gov/topics/earth/features/earth20120104.html
Increasing freshwater on the U.S. and Canadian side of the Arctic from 2005 to 2008 is balanced by decreasing freshwater on the Russian side, so that on average the Arctic did not have more freshwater. Here blue represents maximum freshwater increases and the yellows and oranges represent maximum freshwater decreases. Credit: University of Washington
John from CA
Let’s have a think about this for a moment:
Cronin study:
NASA study:
I still don’t see the relevance to what is happening now.
NODC Salinity
http://www.nodc.noaa.gov/cgi-bin/OC5/SAL_ANOM/showfiganom.pl?navigation=s_an_20112011_2_up_99
BBD,
Salinity and fresh water entering the Arctic from the Atlantic, Pacific, U.S., Canadian, and Russian sides are only a couple of the local factors I think Dr. Curry is alluding to. But, according to the University of Washington study, salinity plays a key role in ice melt and formation.
Since we’re placing importance on sea ice minimum, salinity trends 1979-2012 from March to October would be interesting.
BBD,
The Cronin study relates to the ice age. Fresh water input to the Arctic from the Bering Strait was largely cut off due to the drop in sea level.
John from CA
I did notice that. Which is why I keep suggesting that reduced salinity and consequent deep water Arctic ocean warming during the last glacial aren’t relevant to what is happening now.
Meanwhile, back in the late Holocene, are there studies demonstrating increased salinity in the Arctic ocean *as a whole* over the last decade?
If such exist, has anyone attempted to link this to Arctic summer ice melt over the last decade? Or is this your own hypothesis?
BBD,
The theories stem from the University of Washington studies done by Rebecca Woodgate who actually measures salinity, temperature, etc. in the Bering Strait.
http://psc.apl.washington.edu/HLD/
I haven’t found an extensive study on Arctic salinity but its likely one exists.
John from CA
Thank you for the link to Woodgate’s publication page.
From Woodgate et al. (2010):
Heat flux, not salinity. Which of Woodgate’s papers demonstrating the relationship between Arctic ocean salinity and ice melt over the last decade did you have in mind?
So Woodgate, who ‘actually measures salinity, temperature, etc. in the Bering Strait’, doesn’t provide a study demonstrating an increase in Arctic salinity over the last decade?
Is this salinity/melt causal thing your own hypothesis?
I’ve been trying to locate the specific study and I haven’t turned it up.
I hope I haven’t confused salinity with heat flux.
No luck so far BBD,
I need to knock off for the day. I’ll take another stab at it tomorrow — I know I didn’t make it up.
“In addition to the annual cycle of temperature and salinity, there are important longer-term variations. In particular, the record of salinity through the past decade shows that the Bering Strait inflow to the Arctic freshened about 1 psu during 1991-92 and then remained relatively fresh until 1999-2000, when about one-half of the earlier freshening effect was reversed.”
BBD,
I’m going to admit defeat on the 50% comment. I haven’t been able to locate the source and suspect I misinterpreted the research statements.
Changing Arctic Ocean freshwater pathways
http://www.nature.com/nature/journal/v481/n7379/abs/nature10705.html
“The freshwater changes were due to a cyclonic (anticlockwise) shift in the ocean pathway of Eurasian runoff forced by strengthening of the west-to-east Northern Hemisphere atmospheric circulation characterized by an increased Arctic Oscillation9 index. Our results confirm that runoff is an important influence on the Arctic Ocean and establish that the spatial and temporal manifestations of the runoff pathways are modulated by the Arctic Oscillation, rather than the strength of the wind-driven Beaufort Gyre circulation.”
This is very interesting of course, but nothing to do with accelerating modern Summer Arctic melt .
The buoy data for 2012 show multi-year ice blowing directly out of the Arctic:
http://psc.apl.washington.edu/northpole/DriftTrackMap.html
It doesn’t appear to me that ANY other explanation is necessary.
Particularly when Arctic Ocean heat content, particularly in the areas where ice has declined, appears to be historically low:
http://oceans.pmel.noaa.gov/Figures/oco_heat_2012_web.pdf
Melting ice has a significant cooling effect on heat content. I estimate 3 meters requires 1 billion J/m2 which is certainly comparable with those anomalies.
‘Baby boomers like me have enjoyed the most benign period in human history. The superpower nuclear standoff gave us fifty years of relative peace, we had cheap energy from inherent over-supply of oil, grain supply increased faster than population growth and the climate warmed due to the highest solar activity for 8,000 years. All those trends are now reversing. But it will get much worse than that. The next glaciation will wipe out many countries and nothing will stop that from happening. For example, the UK will end up looking like Lapland. As an indication of just how vicious it is going to get, consider that there are rocks on the beaches of Scotland that got blown over on ice from Norway across a frozen North Sea. As scientists, our task is to predict the onset of the next glaciation.
Onset of interglacials is driven by insolation at 65°N. That is where the landmass is that is either snow-covered all year round or not. It seems that insolation above 510 watts/sq metre will end a glacial period. For an interglacial period to end, the oceans have to lose heat content so that snows will linger through the summer and increase the Earth’s albedo’ http://wattsupwiththat.com/2012/09/16/onset-of-the-next-glaciation/#more-71121 It seems the control variable for an abrupt glacial transition is in place.
Insolation in high latitudes trigger runaway feedbacks in snow and ice but it is something that involves thermohaline circulation . If we are looking at chaotic changes in ice we are also looking at chaotic changes in salinity and temperature in critical areas of the Arctic oceans.
‘Also, when these complex models are forced by reasonably realistic future greenhouse gas projections, they tend not to show an AMOC collapse; the models used in the most recent IPCC assessment suggest that the AMOC is likely to gradually weaken over the 21st century, but not collapse abruptly (Meehl et al, 2007).
However, these estimates for the response of the AMOC to future anthropogenic forcing rely on our “best guess” for many of the complex model details, and do not account for uncertainty in the model input parameters. There are many physical processes that climate models are unable to represent explicitly, and their effects must instead be parameterised. These processes include oceanic mixing and eddy activity, atmospheric convection and cloud physics. Parameterisations generally involve choosing the most suitable value for each coefficient, but it is often the case that there is a range of possible values that the coefficients can take. This means that a climate model has a multi-dimensional parameter space, with potentially billions of model versions (theoretically an infinite number), some with more realistic climates than others. Making climate projections using just one version of a model may mean that certain types of behaviour could be missed. This is particularly important for complex nonlinear systems like the AMOC. It is possible that the AMOC may be more or less stable in different parts of a model’s parameter space. To properly assess the risk of AMOC collapse, we must fully explore the possible responses…
What would happen if the AMOC collapsed?
Model studies suggest that a collapse of the AMOC could lead to a reduction in surface air temperature of around 1-3°C in the North Atlantic region and surrounding land masses, but with local cooling of up to 8°C in areas of increased sea ice (Vellinga and Wood, 2002; Vellinga et al 2002; Manabe and Stouffer; 1997; Jacob et al 2005). A smaller cooling effect would be expected throughout the northern hemisphere, with a slight warming in the southern hemisphere after a few decades (eg., Vellinga and Wood, 2002; Schiller et al, 1997). Several studies suggest that there would be a change in precipitation patterns over the tropics, associated with a southward shift of the intertropical convergence zone (e.g., Vellinga et al 2002; Brayshaw et al, 2009), which could also affect the intensity of the El Nino Southern Oscillation (ENSO) in the Pacific (Timmermann et al, 2007). A collapse of the AMOC may also lead to an intensification of the North Atlantic storm track, with stronger winds over Europe (Vellinga and Wood, 2002; Jacob et al, 2005; Brayshaw et al, 2009). Over a period of years to decades, there would be regional changes in sea level, with a sea level rise in the North Atlantic of up to 80cm (Levermann et al, 2005; Vellinga and Wood, 2008; Kuhlbrodt et al, 2009). Studies also suggest there could be impacts on the carbon cycle (Zickfeld et al, 2008) and on soil moisture and primary productivity of the terrestrial vegetation (Vellinga and Wood, 2002).’ http://climateprediction.net/content/rapid-rapit-what-risk-thermohaline-circulation-collapse
In complex systems there are multiple negative and positive feedbacks and abrupt transitions. Building a narrative around one or 2 components of a large and complex system is likely to result in more heat than light.
‘Thinking is centered around slow changes to our climate and how they will affect humans and the habitability of our planet. Yet this thinking is flawed: It ignores the well-established fact that Earth’s climate has changed rapidly in the past and could change rapidly in the future. The issue centers around the paradox that global warming could instigate a new Little Ice Age in the northern hemisphere.’ http://www.whoi.edu/page.do?pid=83339&tid=3622&cid=10046
Would another consequence of the AMOC collapse be the formation of an Atlantic tropical warm pool comparable with that in the western Pacific that is the source of the world’s highest hurricane frequency?
The following two links seem highly relevant to this thread:
http://stevengoddard.wordpress.com/2012/09/16/correlation-between-arctic-and-antarctic-sea-ice-anomalies/
http://stevengoddard.wordpress.com/2012/09/16/antarctic-ice-area-sets-another-record-nsidc-is-silent/
There is a plethora of empirical and anecdotal data indicating that changes in Arctic ice extent result from natural and cyclical variability.
Dr. Curry, a reasoned stement of ‘it is not so simple and the answer is a multi causal. Polar amplification is true, and can be intuited from first principles of heat flow. Regional ocean current (and possibly atmospheric) influences must also be true. The evidence for this is in the history of Arctic ice variation before AGW could have been a major factor. That it is a complex muddle is shown be the fact that only Arctic ice is diminishing over the past 30 years. The data is at NSIDC polar ice extent anomaly.
Thank you for rejecting jink science, and hewing to the ‘what we know, what we don’t know’ middle way to truth. Not as much “fun” as alarmism or outright denial, but a lot more usefully correct.
The western Pacific warm pool is ENSO driven. We can expect an increase in La Nina frequency and intensity and super cyclones experienced prior to the last century. This is seen in this new and important high resolution SH ENSO proxy.
http://www.antarctica.gov.au/media/news/2012/ice-core-reveals-unusual-decline-in-eastern-australian-rainfall
Hotter in the central Atlantic causing cyclones? Come back when you have a reference or 3 or 4 preferreably – and not simply nonsense narrative from an AGW space cadet. .
Hi there Jim – it is you isn’t it?
One of many jims apparently.
If the Gulf Stream slows down, more heat stays in the tropics. Cooling in some areas means warmer in others. It just makes sense that the warming occurs where the Gulf Stream originates.
I really don’t know what other factors are involved. Cyclones happen when the sst exceeds 26.5 degrees C and there is sufficient energy from planetary spin to spin up the mass of evaporating water. We would need to have warmer water in that limited region of the equatorial Atlantic. Will we get more evaporation carrying latent energy higher into the atmosphere and forming more cloud cloud? Do we get a bigger pool of warm water and therefore more losses overall? With such a complex system we often go far beyond data – and we should take our own narratives with a grain of salt. The problem I think is that we have fallen into a pattern of thinking that is self-reinforcing.
Judith,
This is a nice general overview of where we stand with Arctic sea ice in mid-September 2012, and I look forward to Part II, at which time I will make a longer comment.
A few thoughts:
I agree that 2007 was a regime change, and it’s nice to see this put in these terms, As such, it was not a “black swan” event but a dragon king event that ushered in a truly new regime. However, this regime may be short-lived and its very nature might simply be one of a quick spiral down to an ice-free condition. Now, how much of this dragon king event was caused by human activities and how much was caused by natural cycles is certainly an interested issue to debate, however, it really doesn’t make that much of a difference if we agree that it was a unique combination of the two that precipitated this event, such that it happened when it did because of this combination. This is not to say that it would not have eventually happened anyway at some point given continual anthropogenic forcing, it is just that the timing of sequence was based on natural cycles with the nudge over the edge into a new regime being given by anthropogenic factors.
At any rate, I very much look forward to Part II, and we are very lucky to have someone with your expertise giving us such a comprehensive summary.
Wagathon | September 16, 2012 at 1:38 pm | Reply
Whatever Bastardi believes — that opinion alone should be accorded more than a 50-50 chance of being right.
If Judith Curry finds Bastardi’s authority sufficient to adduce his hypotheis as number II on her list, who doesn’t rate a better than X rating ?
Though Earth’s peak albedo has fallen a whole percentage point in the last decade, there yet survives a cohort able to ignore consequences for radiative equilibrium stark as hurling a bucket of tar at an ice sculpture under the mid-day sun in Singapore.
I wish Professor Curry luck in explaing to them why. this is so, but as long as folks like Sen. Santorum cater to their inability to understand why things do not behave as they are told they will likely remain Bastardi’s lawful prey.
The gratuitous ad hominem attack on a family man when combined with confused aspersions aimed a Bastardi tell a different story–i.e., the Left is seriously lost at sea without Bush to blame and their cries that we are all headed for the edge of the world make humanity look small indeed.
Heck the solar constant dropped 5 points or so in the last decade :) Next thing ya know compacted dirt might contribute to warming even if it is lighter colored than the grass that used to be there.
A minor corection before we move on. The three ponts are described as theories with the thrid being the most likely always – as that is how climate works.
A whole albedo percentage point is 3.4 W/m2 – it is certainly not the case in CERES and is not reflected in ARGO ocean heat content.
To look at the cause of most of the albedo change we need to look at cloud change in MODIS.
http://s1114.photobucket.com/albums/k538/Chief_Hydrologist/?action=view¤t=CERES_MODIS-1.gif
Extracted from – http://lasp.colorado.edu/sorce/news/2011ScienceMeeting/docs/presentations/4e_Kato_SORCE_2011_presentation.pdf
Albedo changes are closely correlated with cloud changes especially in the tropics and sub-tropics.
Here’s on with trends – http://s1114.photobucket.com/albums/k538/Chief_Hydrologist/?action=view¤t=CERES-BAMS-2008-with-trend-lines1.gif
The ‘missing heat’ in the net flux is found iin the oceans – http://s1114.photobucket.com/albums/k538/Chief_Hydrologist/?action=view¤t=vonSchuckmann-OHC.gif – but it was nowhere near as high as you suggest and it was all in the SW.
It has happened before. According to ERBE and ISCCP-FD – all of recent warming was in the SW. ‘The overall slight rise (relative heating) of global total net flux at TOA between the 1980′s and 1990′s is confirmed in the tropics by the ERBS measurements and exceeds the estimated climate forcing changes (greenhouse gases and aerosols) for this period. The most obvious explanation is the associated changes in cloudiness during this period.’ http://isccp.giss.nasa.gov/projects/browse_fc.html
Below you talk about elevations in Antarctic and protection from winds. The sea ice is of course at sea level and Anarctica is the stormisiest and windiest place on Earth. The circumpolar cyclone is not interrupted by land mass as it is in the north and constantly blow from west to east.
You need to be a little more careful and check facts – ideally provide references and links. That you then compound it by obvious warminista rhetoric bodes ill for future contributions to the discourse.
When I wrote my first comment, I thought what I wrote was obvious. Evidently it wasn’t, so let me try again. If we are discussing Arctic sea ice as a regional issue, I have no objections to not discussing the Antarctic at the same time. But our hostess seems to be suggesting that CAGW is having an effect in the Arctic; (I dont agree). But if CAGW is having an effect in the Arctic, it is a global effect, and it must be having a corresponding effect in the Antarctic.
I am trying to choose my words carefully, so no-one misinterprets what I am saying. Because sea ice conditions in the Antarctic are different from the Arctic, we would not expect identical effects at the two poles. But we would expect corresponding effects. Whatever effect is detected in the Arctic should have the same magnitude and sign as the effect in the Antarctic. So, if an effect of CAGW is postulated for the Arctic, the first thing to do is to check whether the corresponding effect in the Antarctic has the same magnitude and sign. If the magnitude and/or sign are different, then it follows that whatever was thought to be a CAGW effect in the Arctic is almost certainly spurious.
That is why I suggest it is essential that the Antarctic be dicsussed at the same time as we discuss the Arctic. Any comments?
I replied to your earlier post. Bottom line, the positive summer albedo feedback is much bigger when the polar area is an ocean. Elsewhere I also note that in the winter there is also a positive feedback in subarctic continents due to reduced snow cover. The southern hemisphere has no significant area of these continents either. The northern hemisphere really has a perfect storm of a configuration of continents and oceans for a positive feedback in all seasons.
“When I wrote my first comment, I thought what I wrote was obvious. Evidently it wasn’t, so let me try again. If we are discussing Arctic sea ice as a regional issue, I have no objections to not discussing the Antarctic at the same time. But our hostess seems to be suggesting that CAGW is having an effect in the Arctic; (I dont agree). But if CAGW is having an effect in the Arctic, it is a global effect, and it must be having a corresponding effect in the Antarctic.
#####################
Wrong on several counts. In a warming world regardless of the CAUSE of the warming there is no reason to expect that the warming will be global or uniform. Like many others you think the term “global” means “everywhere”. it does not. When we say the “global” average increases you need to understand that we mean the average over all the globe. If some places warm more other places will warm less, even cool. In this warming world there is no reason to believe that ice over land must decrease if ice in water at the other pole melts. For one thing the south pole never gets cold enough for the ice on land to melt. It could warm from -40 to -30 and the ice wont melt. At the north pole the sun shines for part of the year and the temperatures get above freezing. The ice is also in the water. here is what we know. we know that the world is warming and we know that in a warming world the north pole ice can shrink while the south pole ice grows. Why that happens is a SEPERATE question from WHY it warms.
“I am trying to choose my words carefully, so no-one misinterprets what I am saying. Because sea ice conditions in the Antarctic are different from the Arctic, we would not expect identical effects at the two poles. But we would expect corresponding effects. Whatever effect is detected in the Arctic should have the same magnitude and sign as the effect in the Antarctic. So, if an effect of CAGW is postulated for the Arctic, the first thing to do is to check whether the corresponding effect in the Antarctic has the same magnitude and sign. If the magnitude and/or sign are different, then it follows that whatever was thought to be a CAGW effect in the Arctic is almost certainly spurious”
##########
Illogical and wrong. there is no reason to believe the sign and magitude should be the same. We know the world is warming and we know the effect is different. Simple as that. the actual facts on the ground show your theory about signs and magnitudes must be wrong. because it is warming, and we see the effects we do.
Steven, Thank you for your long reply. Let me just note that I never mentioned land ice in what I wrote. I am trying to compare sea ice in the Arctic and sea ice in the Antarctic. I fail to see why there would be such a huge difference in effect as you seem ot suggest.
It is also easy for you to say that we should not expect that the effect in the Antarctic to be similar to that in the Arctic, but I am unconvinced.
Steve Mosher wrote:
“Illogical and wrong. there is no reason to believe the sign and magitude should be the same. We know the world is warming and we know the effect is different. Simple as that”
Given Co2 warms the surface, and given that the effect is more pronounced at the poles, two things spring to mind:
1) the effect should reasonably be expected to be of the same sign, even if not the same magnitude – do please remember the talk from “real climate scientists” @ RC both pre and post Steig et al on Antarctic temperature was published. Such talk would seem pretty conclusive that at least the explanation given to lay people, if not the science itself, suggest we should expect the same sign and likely similar magnitude.
2) Even if the above is incorrect and we cannot even expect the same sign, let alone magnitude for both poles, then we most certainly cannot “blame” ALL of the Arctic ice melt on CO2 alone – in that case, local variations are clearly able to dominate over GHG effects, and that would certainly hold true for both warming and cooling. IE, if local effects can override GHG effects, then they can also re-inforce them, giving the unwary cause for concern where none exists.
Jim Cripwell,
Its known as ‘counter-intuitive’ when something happens to produce the opposite effect to what might be expected.
That’s the case in Antarctica, which is geographically very different to the Arctic, where an increase in surface sea ice area, but not total volume, is currently being observed due to increased precipitation and increased surface water run off.
Judith’s written papers on it. So its not just me saying that.
Look, you either accept the science or you don’t. If you do, maybe you could participate in an intelligent discussion. If you don’t, you ask inane questions like how CO2 molecules know they are in the North or South polar regions.
Every time I see photographs of Northern hemisphere glaciers or sea ice I notice that they appear to be grey not white. This may be caused by soot from old diesel engines in the northern hemisphere. Modern diesels, built according to European standards, seem to be ok. But diesel engines seem to last for ever, so there are lots of them that do not meet the standards. Is there any update on this problem?
Coal burning is often a lot dirtier than diesels and on a lot bigger scale.
If one looks at maps of prevailing wind directions, the wind from China blows into the Bering strait region. Over recent years, the coal burning by Chinese power stations and steel mills has changed by orders of magnitude. Most of this is very dirty combustion with little or no cleaning like from precips. Korea is also a big coal burner though the south is generally a lot cleaner burning than the North. It is plausible that at least some of the ice melt has been from the ash. Photos of melt pools in the Arctic have the ash and dust in them. Has there been any real research on the affect of the increased North Asian pollution?
Judith, with regard to your attribution statement, how was the >66% probability calculated? Were there actual calculations or is this an expert opinion. I understand most of these types of probability statements in IPCC documents are based on opinion of one or a small group and not on classical statistical methods of determining probability. Is that correct? If so, why do they do it?
What do you believe (and, are you more a griper or doer)? Do you believe in a digital world and models of reality according to academics who have never held real jobs – models that can be constructed to say anything you want them to say? Or, do you believe in the real world where things happen for reasons we do not always understand but still must deal with, even though it can sometimes be dirty and picking up the pieces can sometimes be messy?
JC says “There are three main theories for the recent decline in sea ice extent and volume,” gives the three, but gives no program for testing which theory is true. If you can’t test it, its not science.
The Amazing Cripwell insists:,i>” if CAGW is having an effect in the Arctic, it is a global effect, and it must be having a corresponding effect in the Antarctic … Whatever effect is detected in the Arctic should have the same magnitude and sign as the effect in the Antarctic. So, if an effect of CAGW is postulated for the Arctic, the first thing to do is to check whether the corresponding effect in the Antarctic has the same magnitude and sign. If the magnitude and/or sign are different, then it follows that whatever was thought to be a CAGW effect in the Arctic is almost certainly spurious.”.
As surface temperture is altitude dependent one might have thought the first thing to check would be a map, as the arctic ice lies at sea level + 9% of its thickness, while the antarctic ice sits several kilometers high in the sky, and the surrounding apron of the stuff is immune to windage because of the circumpolar continent in its midst .
The idiotic addition of CA to GW does nothing to change the drastic assymetry of the situation .
I think Crispwell was referring to the Antarctic sea ice which is growing a slightly larger annual extent which is a little odd when you consider the globe is warming. All the sea ice pretty much melts every year in the Antarctic.
:) I don’t know it I have shown this to everyone, http://en.wikipedia.org/wiki/File:Pack_ice_slow.gif
but it is just fascinating how an area of sea ice greater than the continent of Australia grows and melts every year. One would think if the Earth were a true sphere and in thermodynamic balance hemispherically, that the rate of freeze and thaw would be the same at both poles. I guess Earth just does care to behave like an ideal black body sphere wandering through space.
The presence of different annual cycle characteristics at the two poles is mostly a simple matter of geography: There is no sea ice at the South Pole. On average there is no sea until about 75ºS.
At the other pole sea ice pretty much only exists above 75ºN at the summer minimum, with the maximum extent being constrained by surrounding land.
Not exactly at the south pole but Antarctic sea ice (floating stuff) extent is still 1-2 million k^2 greater than Arctic sea ice.
http://www.climate4you.com/images/NSIDC%20GlobalArcticAntarctic%20SeaIceArea.gif
You do raise an interesting point though but if you’re a warmist it’s an “own goal” kind of point.
Antarctic sea ice, being at a generally lower latitude than Arctic sea ice, has more profound effect on ocean energy budget via albedo i.e. we should worry more about declines in Antarctic sea ice than Arctic. Fortunately Antarctic sea ice has increased slightly over the past 30 years. Or UNfortunately if you’re not an ice hugger. I’m not an ice hugger. Green plants don’t grow well in ice so I’m a fan of less ice.
Arctic sea ice is very near the north pole in the Arctic Ocean. Antarctic sea ice is not at the south pole. There is a lot of land at the south pole. Antarctic sea ice is in warmer oceans. The rate of freeze and thaw can not possibly be the same for sea ice at both poles. The gulf stream warms the Arctic sea ice. The gulf stream does not warm the Antarctic sea ice.
Even if the Winter of 12/13 turns out to be the coldest in recorded history and dead and dying Old Europe loses 10% of its population because of it, too much has been invested by the Left in the grand narrative of global warming to be bothered by the weather. In the meantime though we’ve got to work on the problem of global warming alarmists being paid by the rest of us to do nothing more than gnash their teeth in the ivory towers.
No problemo. Goal posts already moved. It’s “climate change” now not “global warming”. The earth can freeze and it’s still our fault. You see, without people, the climate doesn’t change. I think it’s like the sound of a falling tree in the forest thing… if the climate changes and no one is here to to see change then it didn’t really change. And even if someone was here (ex. Medieval Warm Period and Little Ice Age) but they’re dead now then the falling tree in the forest rule still applies.
Question: How many trees does it take for a clmatologist to conclude from the information they provide that the MWP and LIA never happened. Answer: Just one but it takes as long for them to tell you about it as it took to not happen.
Did you check the comments to the Livina and Lenton discussion paper? Ditlevsen clearly demonstrates that the “bifurcation” is an artefact of the removal of the annual cycle.
Dr Grinsted
I don’t know if you saw my comment here;
http://judithcurry.com/2012/09/16/reflections-on-the-arctic-sea-ice-minimum-part-i/#comment-240471
I am looking for material to enable me to write part two of my article ‘historic variations in Arctice Ice.’
You have written many interesting publications over the years. Is there a well referenced article (from you or others) that deacribes the likely evolution of Arctic sea ice over the past two thousand years in chronological order, which, as far as possible, refers to the geographic areas that melted/expanded?.
Most publications either tend to focus on one small part of the arctic during one limited period, or alternatively encompass the whiole area in a general manner that makes it difficult to focus in on any particular period. Thank you
Tonyb
hmm lots of good russian stuff.
http://www.agu.org/pubs/crossref/2008/2008JC004830.shtml
Bits and pieces
there is other russian stuff going back to 1900.
Mosh
Thanks for that link. I am sure someone must have put together a simple chronological/ice extent reference study during the Holocene, but I’ve not come across it yet
Tonyb
Aslak Grinsted (September 17, 2012 at 2:04 am) wrote:
“Did you check the comments to the Livina and Lenton discussion paper? Ditlevsen clearly demonstrates that the “bifurcation” is an artefact of the removal of the annual cycle.“ (bold emphasis added)
With awareness of neither your comment nor Ditlevsen’s audit, I came to the same conclusion this morning after spending only a few minutes considering the matter.
Here’s the comment I prepared:
–
Livina, V.N.; & Lenton, T.M. (2012). A recent bifurcation in Arctic sea-ice cover.
http://arxiv.org/pdf/1204.5445v1.pdf
Section 1 “Bifurcation detection” begins with “After removing the mean seasonal cycle”.
These authors have mixed states from different times of the year and then catastrophically misinterpreted the stats they’ve calculated. Very concerning, especially considering that this work is being held up as exemplary. Deeply saddening.
If you curve fit the past ten thousand years you will have something valid. If you curve fit 1979 to the present, you will get something that will extrapolate outside of realistic bounds.
why personalize the criticism. there is nothing “saddening” about a mistake. I bet you cry at movies.
Dave
That imo was a stupid comment. Do you know the guy?
Ditlevsen (2012). Interactive comment on “A recent bifurcation in Arctic sea-ice cover” by V. N. Livina and T. M. Lenton. The Cryosphere Discussions 6, C1187-C1190.
http://www.the-cryosphere-discuss.net/6/C1187/2012/tcd-6-C1187-2012.pdf
Elaboration on the arctic sea ice “bifurcation” blunder added here:
http://judithcurry.com/2012/09/16/reflections-on-the-arctic-sea-ice-minimum-part-i/#comment-241199
There was a regime shift in 2007, but let’s not mischaracterize it common senselessly.
Livina, a senior research associate at UEA, replied to Peter Ditlevsen on Sept. 14:
http://www.the-cryosphere-discuss.net/6/C1584/2012/tcd-6-C1584-2012.pdf
Possibly Ditlevsen was so gentle, diplomatic, & collegial that his comment didn’t entirely sink in.
More of the discussion can be found here:
http://www.the-cryosphere-discuss.net/6/2621/2012/tcd-6-2621-2012-discussion.html
The main hub for the article is here:
http://www.the-cryosphere-discuss.net/6/2621/2012/tcd-6-2621-2012.html
This case provides a valuable teaching & learning opportunity. There’s more to say (if/when time permits).
Wag -
I’m with you, but the academics are doing a lot more than gnashing their teeth – they’re robbing us blind, purveying ignorance and preaching the abolition of liberty in their university classes. As a former university professor (American history) myself, I can attest to the fact that higher education can make people dumber, not smarter, and put them farther out of touch with reality.
One of my historian colleagues insisted that the Soviet system was “infinitely” more humane and efficient than ours, and when questioned about Stalin’s mass murders his response was, “Well, it was a necessary step in reforming society.” Another said that retailers always sell at a loss and make it up on finance charges, which, if it were true, would put a quick end to retailing. (Economic literacy, anyone?)
Today”s AGW scaremongers remind me a lot of these guys. If they were only just gnashing their teeth, they might not be so dangerous to liberty and prosperity. Their twaddle would be laughable if it weren’t for its sinister implications for us all. I’m fast coming to think that most climate scientist/politicians are suffering from the same delusions I saw in my fellow historians, Of course you could never get them to admit to error (as Beth Cooper’s reference to l’idee fixe in her BS Detectors comment so cogently and beautifully stated).
Perhaps it all goes back to the regrettable performance of our educational systems in this country, which, unless they major in business subjects, leaves students utterly ignorant of how the world really works. I have come to the conclusion that economics and business principles should be taught assiduously to everyone, starting in the first grade, and that all college and university students should be rrequired to take a full suite of business courses – economics, finance, marketing, organizational management, commercial law and ethical principles. These courses should be mandatory for all students regardless of their major subject or technical specialty.
Another suite of courses that should be mandatory for everyone is in the philosophical foundation and legal basis of liberty – again starting in the first grade, and continuing though college or university.
If this were done, I should think there would be a lot more rational approaches to climate issues and other matters we humans have to deal with, and the sort of malicious nonsense and thievery and disdain for human well-being coming from the CRL/AGW crowd would never gain the sort of traction that it has.
The writing of future climate science textbooks can be safely delegated to home school students, since tens of thousands of blog comments here make it apparent that no one reads the current ones.
This is not to gainsay Georgia Tech’s claim to acedemic elitism, Prof Curry should encourage her readers to take the same remedial mathemeatics course that carried . President Carter on to the institution of higher learning where he mastered radiative heat transfer to the point of being able to extinguish a buring nuclear reactor.
Perhaps Prof. Curry should ask that great populist where he stands on the Sky Dragon issue?
A wild claim about a 1% change in albedo in the past decade and equally idiotic claims about wind shadows in Antarctica in one post. A 100% strikeout rate devolving into incoherence. About par for the course for an AGW space cadet. ‘dif-tor heh smusma’
http://www.flickr.com/photos/haileysimmons/3516787103/
There have been volcano eruptions in recent years in the northern hemisphere. Why wouldn’t increased geothermal heat at the surface make some contribution towards melting sea ice??
I am obliged to blouis for illustrating my point.
Volcanoes account for less than 1% of the total geothermal heat flux, which is in turn ~ 4000 smaller than the solar flux at the Earth’s surface.
Doubling volcanic activity would accordingly add less than one part per thousand to the existing radiative forcing from man made CO2.
Omniloxos, climate scientists think that way, mistakenly. Geothermal heat is real 24hours a day energy. Never mind the flux, count the MJ. Solar flux is cyclic and only affects the transparent surface. I have seen *zero* empirical evidence that changing the composition of a body when subject to alternating heating and cooling cycles makes *any* difference at all to equilibrium temperature, unless the body somehow acts as a one-way heat valve or Maxwell’s demon.
De Buccaneers of Interiors.
===========
‘Have undersea volcanoes caused the Arctic sea ice decline?
A recent study discovered active volcanoes on the floor of the Arctic Ocean, and some people have wondered if they are causing sea ice to melt.
While volcanic eruptions surely warmed the ocean in the immediate vicinity of the eruptions, the amount of heat they produced compared to the large volume of the Arctic Ocean is small. The Arctic Ocean covers 14 million square kilometers (5.4 million square miles), about 1 ½ times the size of the United States or 58 times the size of the United Kingdom. In its deepest spots, the Arctic Ocean is 4,000 to 5,500 meters (13,000 to 18,000 feet) deep. The heat from the volcanoes would have dispersed over an enormous volume and had little effect on ocean temperature, much as a bucket of boiling water emptied into a lake would have little effect on the lake’s temperature.
Second, the eruptions would have introduced heat deep below the sea ice that floats on the ocean surface. The tops of even the tallest undersea volcanoes are more than 1,000 meters (3,000 feet) deep. The Arctic Ocean is strongly stratified, which prevents layer mixing and makes it difficult for any deep water, even deep water warmed by heat from volcanoes, to reach the surface and melt the ice. This layering results from a strong density gradient: water layers near the surface are less salty and therefore less dense, while bottom waters are the densest. Unlike most oceans, where density gradients are determined by both salinity and temperature, Arctic Ocean waters are heavily stratified primarily because of variations in salinity.’
http://nsidc.org/arcticseaicenews/faq/#volcanoes
The Antarctic sea ice melts from below – I will need to think on it and not make insulting comment and idiotic back of the envelope calculations. .
http://theextinctionprotocol.wordpress.com/2012/04/26/antarctic-ice-melting-from-below-reveals-satellite/
@RobertEllison, of course ice melts from below – you can see that every day if you put ice in a glass. The specific heat capacity of water to conduct has a much bigger impact than the insulating capacity of air. Somehow, climate scientists think warm water sinks and solutes don’t dissolve and Maxwell’s demon keeps the earth warm.
The recent heat seems to have vulcanized poor Ellison’s brain to the point of forgetting John McCarthy’s warning to wannabe pundits: He that refuses to do arithmtic is doomed to speak nonsense
At las=t account, the area of the earth’s surface was ~ 500 million km2, and the albedo of water was .06
Compared to the decade previous, this summer’s Arctic summer ice loss of 4.1 mKm2 sea ice plus ~1.5 m km2 of land ice melting ,on Greenland and other Arctic islands, considerably exceeds 1% of the area of the Earth
As oceam albedo is only .06, and arctic land albedo is low as well, the result approximates a 1% global albedo loss.
Not even close to 1%, dopey. Insolation is tiny at the poles. Ice can’t reflect energy that doesn’t arrive.
http://oceanworld.tamu.edu/resources/ocng_textbook/chapter05/Images/Fig5-8A.htm
23W/m2 average annual insolation at the poles. About a tenth of that in the tropics. So reduce your 1% to 0.1%.
Actually being off by only a factor is pretty good for a warmist so if I’m grading on a curve against your peers you get a C+.
Funny boy. ‘Everything that can be counted does not necessarily count; everything that counts cannot necessarily be counted.’ Albert Einstein. Although as an engineer and environmental scientist – I quite like numbers. Temperatures in Aus btw are quite moderate.
Your simplistic calculation needs several other factors to be believable – indeed it is not believable at all.
Insolation?
http://s1114.photobucket.com/albums/k538/Chief_Hydrologist/?action=view¤t=insolationwithlatitude.png
Ocean albedo?
‘Measurements at a sea platform show that the ocean surface albedo is highly variable and is sensitive to four physical parameters: solar zenith angle, wind speed, transmission by atmospheric cloud/aerosol, and ocean
chlorophyll concentration.’
Clouds?
http://www.arctic.noaa.gov/detect/climate-clouds.shtml
http://nsidc.org/arcticmet/factors/clouds.html
Seasonality?
You busily insult everyone which I suppose is your only point. The rest is utter nonsense.
I think I’ve never heard so loud
The quiet message in a cloud.
Weary, plotting, forth the plod;
Arfa-Omega oxylocks clod.
================
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John from CA | September 16, 2012 at 3:22 pm | Reply
A warmer Arctic Ocean during ice age times
http://www.geo.su.se/index.php/news/544-a-warmer-arctic-ocean-during-ice-age-times
“Based on their results, the researchers conclude that the Arctic Ocean has a previously unrecognized high sensitivity to changes of the freshwater input over multiple timescales, which is manifested in large temperature excursions of the intermediate water layers.”
This should come as no surprise. Ice is a great insulator.
BandwagonConsensus climate boffins are getting surprised by the data with alarming regularity. It’s a travesty.Thanks to David Springer for confirming the disconnect between elementary science texbooks and what climate cranks say:
Albedo is a measure of global relectivity, not Arctic solar flux.
He grossly understates that as well : daily average solar radiation over the North Pole peaks at a midsummer value 36 % higher than the Equator ( CF Serreze and Barry, 2005).
Excuse me for pointing you to a physical oceanography textbook used by Texas A&M University and in particular to Figure 5.8 Global map of annual-mean insolation into the sea in W/m2 calculated from the ECMWF 40-year reanalysis. From Kallberg et al 2005.
What the f*ck are they teaching those kids at TAMU! Write to them right away OMONILOXOS and set them straight. Be sure to emphasize that you are the great OMNILOXOS. ROFLMAFAO@U
Albedo needs to be taken in context, Omnilocust. The alebdo of my white ass is approximately 0.95 but it doesn’t see much sun so it really doesn’t matter what its albedo is. The polar areas are like my ass. Now if you’d pull your head out of yours the daylight might help you see that I’m correct.
Serreze and Barry, 2005 is TOA insolation. I referred you to Kallberg, 2005 which is how much of that insolation actually makes it to the surface. For instance we can go here:
http://aom.giss.nasa.gov/cgi-bin/srmonlat.cgi
and get a table of calculated TOA insolation and find that annual average at TOA for 90N is 173W/m^2 while at 0 degrees it is 417W/m^2.
But when we go to Kallberg 2005 surface insolation
http://oceanworld.tamu.edu/resources/ocng_textbook/chapter05/Images/Fig5-8A.htm
we find the tropics gets over 200W/m2 at the surface while the Arctic gets only 23W/m2.
It doesn’t get much more sciency than this, Omniwhatever. You’re wrong. Be a man about it for once in your life. Or go change your handle to something else so this little brainfart of yours doesn’t follow you around. Maybe some day you’ll acquire enough confidence in your knowledge to use your real name. Obviously that day isn’t today.
Y’all ought to read this:
http://geotest.tamu.edu/userfiles/216/dessler2012.pdf
Observations of climate feedbacks over 2000-2010 and comparisons to climate models
A.E. Dessler
Dept. of Atmospheric Sciences
Texas A&M University
College Station, TX
979-862-1427
adessler@tamu.edu
Published in AMS Journal of Climate. Link goes to a peer-approved pre-press version that isn’t behind a firewall.
Control GCM ensemble using internal variability only got it right for the period 2000-2010. The GCMs using external variability (long term AGW) screwed the pooch.
The author goes on to say we don’t understand clouds very well and warns not to get complacent about AGW just because internal variablity has stabilized the climate from 2000-2010.
Too bad Dessler didn’t add on the period 2010-2012 because global average temperature took a real nose dive since then.
http://www.woodfortrees.org/plot/wti/from:2010/plot/wti/from:2010/trend
Wait for it. Facts eventually speak for themselves and in the meantime they have me to speak for them. ;-)
At 3:59, Texan oceanography textbook owner David Springer informed us in high dudgeon :
“Not even close to 1%, dopey. Insolation is tiny at the poles. Ice can’t reflect energy that doesn’t arrive.
http://oceanworld.tamu.edu/resources/ocng_textbook/chapter05/Images/Fig5-8A.htm
23W/m2 average annual insolation at the poles. About a tenth of that in the tropics. So reduce your 1% to 0.1%.”
By 8:40, after being confronted with the facts of the case, and perhaps consulting one of those unread climate science texts that form the theme of my narrative, he wisely retreated from ” tiny” to the textbook value he earlier denied, informing those that didn’t already know that ” annual average at TOA for 90N is 173W/m^2 while at 0 degrees it is 417W/m^2.
Since the sun heats the atmosphere from the top down the rest of his rant signifiies less than his continued attempt to redefine a parameter as elementary as ‘albedo ‘ .
For that he gets an F, which is a very respectable mark in all hat and no cattle country. Too bad .Texas had great oceanography until the Permian came along.
The sun heats the atmosphere from the top down?
HOLY CRAP! Your ignorance knows no bound!
From the top down(above), by a continuation of the oceans, and other means.
===============
I was leaving that alone Kim – truly couldn’t be bothered.
Twice again, thrice again, into the breach.
===================
But does anything make your simple minded calculation any more credible?
‘Albedo is a measure of global relectivity, not Arctic solar flux.
He grossly understates that as well : daily average solar radiation over the North Pole peaks at a midsummer value 36 % higher than the Equator ( CF Serreze and Barry, 2005).’
How’s that wikepedia textbook working out for you? The average solar radiation at the poles is 36% higher in summer at the poles because of a 24 hour day. But it is almost as high at 23.5 degress of latitude. Insolation is less but it lasts longer. A passing thing fading from the summer solstice. The annual average is about 0.25 of the peak – but you expect as well that the reflected SW would not vary as much as you suggest albedo of oceans being influenced by ‘solar zenith angle, wind speed, transmission by atmospheric cloud/aerosol, and ocean chlorophyll concentration.’
You have to get insolation before it is reflected. The definition of albedo is the proportion of reflected SW. Albedo = SWout/Sin. Simple hey. The other points I introduced you would be well advised to reflect on also.
Great to see Ellison back– nothing rounds out a climate blogs bona fides as a crank magnet better than someone with a self published one-equation-radiational Theory of Everything. :
http://www.earthandocean.robertellison.com.au/A%20new%201st%20order%20differential%20global%20climate%20change%20equation.pdf
And, wait for it , not a single scientific publication to his name.
Who ever would have guessed from this exchange ?
On the end, will be proven that: ignoring my proofs, will decimate the ice and that will bring more freezing winters in Europe & north America. let it stay as a record! ::::
1] bigger and bigger ”dry heat” produced in sub-Sahara (lake Chad is getting dry) -> extra dry air goes west into north Atlantic and destroys the ”raw material” for renewal of that ice. (Sirocco winds start blowing from Arctic, south -> to avoid vacuum -> moist air from North Atlantic goes north and replenishes the ice deficit. Less moisture in north Atlantic = less raw material for Arctic (same ”extra dry heat created, will slowly devastate the Congo basin -> dry heat will double in strength) Climatologist declared that ”raw material” as bad for climate…?! http://globalwarmingdenier.wordpress.com/2012/07/20/water-vapor/ Otherwise, there are still prevention and solutions for the real problems; but NOTHING to do with CO2 +phony global warming CON!
B] higher ”dry heat” produced in Sahara = higher evaporation in the Mediterranean -> the Gulf stream increases speed -> more water from Mexican gulf -.> more ”extra” water siphoned from under the Arctic ice. C] that ice to protect itself from the salty seawater – sacrifices from itself some, to create freshwater -> stronger current = more and more sacrifices. PLUS, shonky experts and spectators go and for them the big Ice Crusher ships are vandalizing more ice by making many corridors -> ruff water, because of that, damages after 10000 times more -> they are rejoicing for being ”less ice”…
C] ice as the best insulator, protects the water from the unlimited coldness in the air. No ice -> water absorbs extra coldness -> in combination with the coldness in the air, as ripples -> intercept the moisture south = double the snow south in Europe & USA- no moisture left for renewal Arctic’s ice (if you know reliably, where ice is missing – from there where winds blow in January south = can predict where is going to happen, what happened last season in central Europe – for 2-3 y before, in northern Europe +USA) You people can ignore my proofs; but the weather will not… hope this year to be in north Europe + north america – where the shonky ”CLIMATE MODELERS” are. The bigger blizzards there – climatologist will not be fashionable; they are shooting themselves in the foot, by rejoicing the less ice on arctic. The ”Devil’s Advocates” will start getting what they deserve, not more cash.
2] 80% of water from the Russian rivers drain into the Arctic -> spread on the top of the salty / heavy water and protect the ice. Less of that freshwater -> Arctic siphons ‘extra” warm / salty water from north Pacific, via Bering’s death to the ice. Those ”death spirals” are created by the ”Warmist misleadings”; NOT by natural variations. Misleading that: the non-existent GLOBAL warmings & CO2 are controlling climate, instead of H2O. That’s why they are wrong and back to front on everything:: http://globalwarmingdenier.wordpress.com/midi-ice-age-can-be-avoided/
ALL HONEST PEOPLE SHOULD COPY THIS COMMENT, AND KEEP IT AS A RECORD.
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