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Comments 120051 to 120100:

120051. HumanityRules at 11:27 AM on 6 May 2010
        Kung-fu Climate
        Thanks for that Rob, Something that's been bugging me for a while is the way instrumental temperature records are pasted onto the end of these graphs. Can you just confirm that there is no issues with doing this? I don't mean your attempt just the general practice of doing this. I remember the recent post about the Mclean paper specifically critisised this sort of splicing of data sets.
        Response: The problem with the McLean paper was the way they spliced the data - they hid the splicing boundary by breaking the graph into different boxes, they used different Y-axes for the different boxes and the way the data overlapped, the splicing also hid the incline in temperature. This problematic graph was then cited by the authors as proof that humans weren't causing global warming.
        
120052. ProfMandia at 11:21 AM on 6 May 2010
        Kung-fu Climate
        Rob, You have achieved what many fail to do: you have done science and you have done so with a story. Essentially, you have kept the novice interested which means your message was received. Kudos to you. Alan Alda would be proud of you. Scott A. Mandia, Professor of Physical Sciences Selden, NY Global Warming: Man or Myth? My Global Warming Blog Twitter: AGW_Prof "Global Warming Fact of the Day" Facebook Group
120053. Spencer Weart at 11:19 AM on 6 May 2010
        Kung-fu Climate
        I don't have access to Loehle's paper, but I note from the abstract that he derives his result by averaging 18 series. Most such data comes from the Northern Hemisphere, so that's probably what he is mainly measuring. Fair enough, so did the original Mann hockey stick and many others. We should note, however, that there is considerable historical evidence of an ocean "see-saw" whereby when one hemisphere warms, the other one cools. The MWP may therefore not have been a global phenomenon, and indeed this is what Mann's most recent work tells us. Now here comes the kung fu move. The current situation is strikingly different, since for sure both hemispheres are warming together. The argument that we have seen something like this before, therefore, is mere speculation, since strong warmth in the S. Hemisphere in the Medieval period has not been demonstrated.
120054. nautilus_mr at 11:14 AM on 6 May 2010
        Kung-fu Climate
        John, a quick suggestion: would you mind editing the paragraph before Fig 3. to indicate which colour lines relate to which studies?
        Response: All the other reconstructions come from this Wikipedia page which includes the sources along with each colour.
120055. scaddenp at 11:06 AM on 6 May 2010
        Where is global warming going?
        "The boring thing is that G&T are just applying traditional thermodynamics and find that the CO2 AGW theory just does not stack up." They are misinterpreting classical thermodynamics. Consult a text book. ( eg Fundamentals of Heat and Mass Transfer). This was covered well at: The imaginary second law
120056. kdkd at 10:42 AM on 6 May 2010
        Where is global warming going?
        suibhne #83 Please excuse my rusty chemistry, but I think you've made a fundamental error. Please correct the below if it's wrong. The IR absorption of CO2 has very little to do with the electron energy levels (except from the context of forming the bonds in the first place). The bond energy in the CO bonds in a co2 molecule is around 1500kj per mole of CO2. So in order to break the bonds of the co2 molecule you have to supply 1500kj of energy to 1 mole of co2 molecules before the bonds break, and the energy levels of the electrons come into play again. Again, my chemistry is very rusty, but this is my understanding. I really don't think that quantum effects are relevant at all in the way that you are claiming they are.
120057. Chris G at 08:34 AM on 6 May 2010
        A visual depiction of how much ice Greenland is losing
        notcynical (#72), Applying localization and rainfall amounts, that's a neat 'trick'! I'm putting that in my bag for later use.
120058. Doug Bostrom at 08:13 AM on 6 May 2010
        Where is global warming going?
        Suibhne, in order to say "they just don't", you must also say what they do. What do photons emitted from a cool body do when they encounter a warmer body?
120059. Riccardo at 07:30 AM on 6 May 2010
        Where is global warming going?
        suibhne, nice reply: "they just don't". In fact they do, as already shown. P.S. review your quantum mechanics and in particular how bosons work.
120060. chris at 07:20 AM on 6 May 2010
        What causes Arctic amplification?
        slightly off the point but possibly of general interest: The European Geosciences Union annual meeting currently underway in Vienna have put some of their summary "Press release" presentations on line as webcasts. There is an interesting presentation by Peter Wadhams entitled "Arctic sea ice is in terminal retreat" available from here. The question/answers session at the end is interesting.....
120061. suibhne at 06:53 AM on 6 May 2010
        Where is global warming going?
        doug_bostrom In order for your assertion to be true, photons emitted from a lower temperature source must somehow be unable to interact with surfaces radiating at a higher temperature. Well they just don't. KR (78) puts it quite well. Here's my guess from Quantum Mechanics. The higher temperature energy levels will already be full from bottom up. Lower energy photons will not find any "slots" to fill and will be at something of a loose end.
120062. suibhne at 06:44 AM on 6 May 2010
        Where is global warming going?
        KR This is what your link led me to! To ensure top quality, review articles are by invitation only and all research papers undergo stringent refereeing. We welcome you to submit your research papers to IJMPB for publication. You say further .....If you want to claim that the last 100 years of thermodynamics, radiation equilibrium ... are wrong. Who wants to claim such nonsense. The boring thing is that G&T are just applying traditional thermodynamics and find that the CO2 AGW theory just does not stack up.
120063. Philippe Chantreau at 03:29 AM on 6 May 2010
        Rain in the Canadian High Arctic in April?
        Interesting facts Mauri. I won't hold my breath to see it reported on the "skeptic" web sites where the record February snow cover was trumpeted as some sort of proof of something or other...
120064. Doug Bostrom at 03:24 AM on 6 May 2010
        Are we too stupid?
        What sort of philosophy produces the following behavior? It was hailed as a breakthrough in the fight to cut carbon emissions. In 2007, researchers found that heavy electricity users cut their consumption after being told that they used more energy than their neighbours. Almost a million US households have since received similar feedback and have cut electricity use by an average of 2.5 per cent. But a new study has identified a wrinkle in the plan: the feedback only seems to work with liberals. Conservatives tend to ignore it. Some even respond by using more energy. The findings come from a study of over 80,000 Californian households, just under half of which received feedback on energy use. Overall, the technique worked: households who got the feedback cut electricity by around 2 per cent, say Dora Costa and Matthew Kahn at the University of California, Los Angeles. But important difference emerged when Costa and Kahn looked at the political leanings of those in the survey. Homeowners who identified themselves as Republicans cut energy use by just 0.4 per cent on average. And those Republicans who showed no practical interest in environmental causes – people who did not donate to environmental groups and did not choose to pay extra for renewable energy – even increased electricity use by 0.75 per cent. Republicans won’t be nudged into cutting home energy Why would somebody behave like that? I can understand doing nothing, but actively increasing one's electric bill as well helping to erase efficiency gains? What's up with that?
120065. mspelto at 00:31 AM on 6 May 2010
        Rain in the Canadian High Arctic in April?
        Sometimes an event such as the rain even here is spatially or temporally limited and of as such is an isolated weather event. If it coincides with other events spatially and temporally then it is just another measure of a broader event that is important. For example February had the 3rd highest mean snowcover extent of the last 44 years in North America according to the Rutgers Global Snow lab. The most extensive melt off of snowcover in the last 44 years has occurred in March and April. Leading to March mean snowcover extent being the 18th of 44 years, and April being the 41st highest of 44 years. That is correct going from third most to third least snowcover. This indicates a continent wide period of unusual melt conditions.
120066. michael sweet at 22:23 PM on 5 May 2010
        Rain in the Canadian High Arctic in April?
        Westwell: Perhaps your reporter in the Hawaii story should have reported on ice in the great lakes last year, since they used data from last year. There was a lot of ice in the great lakes last year. It was a La Nina year. This year, in contrast, was record lows. Last year was high for recent years, but not record highs. It is easy to cherry pick data to try to influence people who are uninformed. You will have a lot more trouble on this site where people check what you say.
120067. Westwell at 21:54 PM on 5 May 2010
        Rain in the Canadian High Arctic in April?
        Climate change? Global warming? Maybe it's just the weather, did anyone think of that? Lots of Ice—But No Media Coverage http://www.hawaiireporter.com/story.aspx?0b9e4b5f-5225-40c7-b775-03c822fbffc8 Catastrophic” retreat of glaciers in Spitsbergen http://wattsupwiththat.com/2010/05/02/catastrophic-retreat-of-glaciers-in-spitsbergen/
120068. Juergen Wanninger at 21:41 PM on 5 May 2010
        Flowers blooming earlier now than any time in last 250 years
        Hello Argus, thanks for your answer. However if you are looking only for short periods, the typical climate oscillations which happened always in the past independant of Co2, will show exaggerated tendences. But if we look at longer times and only 'normal' periods (not those being famous for their extraordinairy cold climate like Maunder or Dalton) we can suddenly see, that the nature is not as much 'alarmed' like lots of people or our politicians. Each month the press shows new temperature diagrams commented with messages of 'new temperature records'. But my personal daily experience in the last 30 years does not show a 'Michael Mann' - heating. And the above diagram confirms my experience. Obviously the short warm period between Maunder and Dalton minimum looks having been as warm as today - however there was a much smaller Co2-concentration in the atmosphere at that time. If wee can confirm the above work by further groups and examinations, what would that mean for the theory of Co2-driven global warming? I think this will mean at least, that the predicted amount of warming due to Co2 is estimated extremely too high! Doubling should give 0.5 degrees, like Lindzen says. And there should be other things beneath Co2 driving our climate! Maybe Svensmark is on the right way?
120069. Argus at 17:38 PM on 5 May 2010
        Flowers blooming earlier now than any time in last 250 years
        Thank you Juergen for this sobering time perspective on the 'alarming' news of early blooming! To me it looks like spring has moved three to four days within the last 250 years, so it is exactly in line with your 25800 year period. No cooling. But let us not forget that between the first and the last period in the whole diagram there are also striking maxima and minima. What if a diagram-interested scientist 100 years ago had concentrated on the period 1840 to 1910? ''Alarming news! Flowers now blooming 12 days earlier than 70 years ago!'' Or take 1920 to 1970: '' New ice age imminent! Spring now comes five days later than just 50 years ago!''
120070. KR at 15:41 PM on 5 May 2010
        Where is global warming going?
        The IJMPB review paper policy is described here - Gerlich and Tscheuschner (2009), FALSIFICATION OF THE ATMOSPHERIC CO2 GREENHOUSE EFFECTS WITHIN THE FRAME OF PHYSICS, was definitely not peer-reviewed. And, sadly, it's junk...
120071. SoundOff at 14:13 PM on 5 May 2010
        Rain in the Canadian High Arctic in April?
        #24 - Pete, It’s a regular pattern, at least in east central Canada. Each El Niño episode does give us very mild winters. And colder winters result when a La Niña episode is in effect (such as the prior two winters before this last one). So yes ENSO does have a long reach. Keep in mind that Toronto is slightly closer to the equator than to the North Pole, at the same latitude as southern France (but without the palm trees), so we get influenced by both ends. Perhaps in the far north, the Arctic Oscillation normally dominates. I did notice that Canadian Arctic surface temperatures were significantly above normal, while at the same time the Canadian prairies and US plains states were freezing under the deepest part of the negative AO. There’s much supporting science that says the stratosphere above the Arctic warms during the negative phase of an AO but little science making such claims for surface temperatures. So I’m not prepared to say that a negative AO typically results in warmer Arctic surface temperatures. Analyzing it logically, if the air pressure is high in the north and low in the mid latitudes (a negative AO), then what one should see is the surface air moving generally from north to south (from the high pressure area to the low pressure area). This in turn should pull down some upper atmosphere in the north to replace the exiting air, which in turn, pushes the higher level jet stream to move in the opposition direction to fill the high level void created in the north, and lifting air out of the south to complete the circle. These movements would all have a slight eastward slant due to planetary rotation. With colder high level air being pulled down in the north, one would expect things to be a bit cooler up north on the surface, and some minor ice extent recovery this past winter is evidence that this did happen overall. But how does one explain the warm surface temperatures I noticed in the north at the peak of the negative AO? I don’t know but perhaps, with an El Niño raging on top of the usual GW and a negative AO, just maybe a layer of warm Pacific air was being pulled in below the north and east moving jet stream during that same time and it was filling the surface viod in the far north instead of higher air. Weather is very chaotic so it’s hard to say. The early rainfalls reported in this article were well after the negative AO peak (but still within the ENSO influence), so we might have moved off topic by discussing AO here, but it was worth considering nonetheless.
120072. Doug Bostrom at 11:21 AM on 5 May 2010
        Where is global warming going?
        Suibhne, what you said is that back radiation cannot do any work. In order for your assertion to be true, photons emitted from a lower temperature source must somehow be unable to interact with surfaces radiating at a higher temperature. Can you describe the mechanism that isolates and sorts photons in this way?
120073. actually thoughtful at 11:08 AM on 5 May 2010
        Rain in the Canadian High Arctic in April?
        #24 - can you make your point differently? Are you saying warming arctic corresponds with negative AO? The opposite? Something different? A quick review shows that AO is not strongly correlated with temperature in 1999 and 2005 (notably hot years...).
120074. muoncounter at 10:26 AM on 5 May 2010
        It's cooling
        And its been 90 here (on the coast of that great bowl of oil and vinegar we call the Gulf of Mexico) already - two days running. However, this new study suggests that we ain't seen nothing yet. "Researchers for the first time have calculated the highest tolerable "wet-bulb" temperature and found that this temperature could be exceeded for the first time in human history in future climate scenarios if greenhouse gas emissions continue at their current rate."
120075. KR at 10:21 AM on 5 May 2010
        Where is global warming going?
        Incidentally, that's an abuse of IJMPB's own editorial system. A "review" paper should consist of describing the state of the art in a field, listing significant contributors, seminal papers, and directions for future research. If you want to claim that the last 100 years of thermodynamics, radiation equilibrium, and climate theory are WRONG, that's original research (certainly an original opinion), and deserves peer review - which G&T did not get. The editors of IJMPB simply published a long polemic - one that had been solidly refuted ages ago by people with actual knowledge in the field.
120076. KR at 10:14 AM on 5 May 2010
        Where is global warming going?
        doug, Riccardo, folks, my apologies - I referred to an earlier topic without sufficient attribution/context. The 324W/m2 number comes from an earlier thread, Is CO2 a pollutant, where suibhne argued at length against GHG heating, using as a reason the G&T paper. My most recent (and sadly a little rough) posting was in response to seeing G&T arguments against greenhouse gas heating again; not the energy flows at Earth's surface. And yes, you can extract some energy using the photoelectric effect (which is how the detectors for IR work), but that energy isn't usable in a heat engine without a cold sink. suibhne, it turns out that the G&T paper was NOT PEER REVIEWED; it appeared in International Journal of Modern Physics B as a review paper, not a research paper - invited by the editor(s) on a topic of their interest, and very definitely not subject to a peer review process. No peer review, hence no checks by anyone actually knowledgeable in the field, hence I have even less reason to take any arguments from G&T seriously.
120077. Riccardo at 08:09 AM on 5 May 2010
        Where is global warming going?
        suibhne, we're way offtopic here. The short answer is costs and efficiency.
120078. suibhne at 07:42 AM on 5 May 2010
        Where is global warming going?
        doug_bostrom As I said to KR in post70 ............... the figure of 324W/m2 Back Radiation. Why is this huge magnitude of photons not put to some useful work? If this could be shown I would have to reconsider the whole issue. Yes and I stand by this statement.
120079. chris at 06:04 AM on 5 May 2010
        Tracking the energy from global warming
        Ken Lambert at 11:55 AM on 3 May, 2010 O.K. fair enough Ken; we've pretty much come full circle and arrived back where we were a few days (and many posts!) ago. For a short period (largely 2006-2008) there was a brief reduction of sea level rise which has brought the trend down a tad when measured over a very short time period. However the sea level rise has now more or less caught up with the long term trend around 3-3.4 mm.yr-1. It is reported at the European Geoscience Union meeting this week that the recent ARGO ocean heat content meaurements are showing significant rises again (I've just heard this from a colleague; no doubt this will be discussed/published more widely in due course). Since glacial/polar ice melt is seemingly increasing (and as we have both pointed out on this thread, this seems to have contributed a larger proportion of sea level rise in the last 6-7 years than during the previous decade), and since measured upper ocean heat content may well be on the rise again, and the sun has grudgingly started its rise up the ascending limb of the solar cycle, it wouldn't be surprising if the rate of sea level rise made another acceleration. The point is that anomalies during very short time periods need to be interpreted with caution. It's possible that the apparent stutter in sea level rise/upper ocean heat content was due to some heat transfer to the deeper oceans which warm with a lesser contribution to thermal sea level rise than surface waters. Perhaps there was an anomalous period of atmospheric behaviour (clouds/aerosols). Perhaps some of the heat has just "disappeared".... We don't really know yet. That's actually the point of Trenberth's recent publications on this subject. My original post was to point out that Peter Berenyi's analysis (that the apparent energy budget "defecit" "bring(s) havoc to standard greenhouse theory" is unscientific. It really isn't helpful to unleash profound interpretations based on throwing numbers at very short time periods especially in the circumstance (Trenberth) that our measuring systems, though greatly improved during the last decade, aren't yet up to the task required for a full accounting of short term phenomena.
120080. Riccardo at 06:00 AM on 5 May 2010
        What causes Arctic amplification?
        Arkadiusz Semczyszak, not sure I understand your point. The paper main focus is on the vertical structure of the temperature anomaly following the new ERA-interim reanalysis. The latter is in constrat with previous reanalysis datasets: "We diverge considerably from ref.8 [Graversen et al., Nature 451, 53–56(2008).] in finding that the maximum Arctic warming is at the surface and that warming lessens with height in all seasons except summer. This vertical structure suggests that changes at the surface, such as decreases in sea ice and snow cover, are the primary causes of recent Arctic amplification." So, they are not discussing the origin of the warming but the feedback that can be inferred from this new reanalysis.
120081. Doug Bostrom at 04:45 AM on 5 May 2010
        Where is global warming going?
        Just to amplify Riccardo's remark, one could in principle arrange an array of photovoltaic IR detectors to liberate mechanical energy via an electric motor, aka "do work" in the most prosaic sense. With such an apparatus pointed skyward on a cloudy night, even if the detector array IR radiation temperature was higher than the cloud IR radiation temperature one would still be able to see a net increase of electrons flowing from the IR detectors and ultimately liberating their energy as heat at the motor, compared to the same arrangement pointed at a clear sky. Photons arriving at the detector array neither know nor care about the temperature of the array itself. They are not somehow driven back because the detector is warm, they plow into the surface regardless where they stand the usual probability of bouncing an electron. G&T's paper lacks perspective.
120082. Pete Dunkelberg at 04:42 AM on 5 May 2010
        Rain in the Canadian High Arctic in April?
        That 1 or 2 degree warmer area in the tropical Pacific has a long reach! Or, from your link "This [the positive phase of the AO] keeps much of the United States east of the Rocky Mountains warmer than normal, but leaves Greenland and Newfoundland colder than usual. Weather patterns in the negative phase are in general "opposite" to those of the positive phase, as illustrated below." When the wind blows hard from the Arctic, the Arctic does not become a giant vacuum. Other, warmer air blows in from elsewhere. The slightly warmer air from the tropical Pacific, even if it gets there without cooling much, could not account for the very high arctic temperatures. What does it is the quantity of air from lower latitudes, which must match the quantity of air blowing out of the Arctic. I had hoped that mentioning the AO would make a light bulb go off. How does it correlate with warm Arctic years in the past?
120083. Doug Bostrom at 04:24 AM on 5 May 2010
        What causes Arctic amplification?
        Here's that link to information about the Southern Hemisphere and Antarctic again, johnd. Worth reading. Your original concern was about differences in response of the two hemispheres to a deranged energy budget. The reasons for why this is true are well understood; glancing at a map of the globe shows us why we should not expect the two halves of the planet to behave identically. The takeaway is, we've got a good grasp of why the Southern Hemisphere diverges from the Northern Hemisphere w/regard to a deranged energy budget. The effects you mention are interesting but in terms of budget they're akin to worrying about plugging a nickel into a parking meter when the payment on your automobile is $500USD/month.
120084. Jim Eager at 03:29 AM on 5 May 2010
        What causes Arctic amplification?
        Hmmm, seems the much vaunted "recovery" of arctic sea ice lasted barely one month.
120085. Jacob Bock Axelsen at 03:25 AM on 5 May 2010
        Are we too stupid?
        embb This supposes that "we" is a powerful coalition of states that will act in concert and has enough economic clout to make these threats realistic. Do you have any example of such coalitions? How do you explain the international stop for leaded gasoline, CFCs, DDT, thalidomide, phthalates, asbestos etc.? Can you prove there was no reciprocity involved? Does it not involve negotiated treaties between states? There are plenty of strong coalitions. EU, G8, G20, NAFTA etc. All they have to do is agree. The more that joins the easier the transition. What you say is that if you already have a powerful coalition then you can have a powerful coalition. You did not understand that a small cluster can eliminate all defectors by growing bigger. No circular logic. It is part of the dynamical properties. You have to read some of the papers to understand these effects. Since you did not answer my question I must conclude that you have not read any of them and do not wish to understand more than you already know. Is that correct? There is no short term environmental gain in reducing the emission of CO2 as it is not a pollutant. Not according to the EPA. Second, there are also both immediate and future health effects of climate change. Do you think voters favor cash in return for a destroyed planet? Long term environmental gain in a hundred years say, is a matter of debate e.g. Germany's efforts will cost billions of euros and would reduce the temperature by less then 0,2 degrees in a hundred years. Is there anything that is certain? How do you know that it is not worth billions of euros to mitigate climate change even by 0.2 degrees? How about diversifying your suppliers ? Way cheaper then emission reduction I guess. Such as deploying more dangerous oilrigs? How do you make your assertion as to the price? Did you know that the compounded price of a gallon of gasoline in the USA could be as high as 15 dollars due to taxation, regulation, environment protection etc.? Of course, that is not even counting the price of the health insurance and mitigation of climate change. How about diversifying the sources instead? What is it exactly about biofuels, windmills, solar power, geothermal heat etc. that you oppose so much? China is already ahead of the USA in many areas, which also seems to contradict the notion that it does not pay off to mitigate climate change. How do you explain that? Is it the free market? All I know is that there is a large risk of proposing the wrong solutions with the idea that we have to do something. So you argue for the preservation of the status quo because the proposed reforms may be imperfect? That is why I conclude that you have an interest in not mitigating climate change. Luckily, reforms can be passed with a majority alone and they are coming. Economic war would be one such - and you seem to have no other solutions I have provided my solutions here, here, here, here, here and here. Trade war based on science is infinitely less harmful than real war based on dangerous nationalistic issues. If the trade war solves the problem due to the fact that reciprocity works to eliminate defectors, then how can you possibly oppose it?
120086. embb at 01:45 AM on 5 May 2010
        Are we too stupid?
        Jacob:You defect to fulfill your emission goals, we punish through trade restrictions, UN resolutions, treaties that disfavor your interests, making the IMF put conditions to loans during economic downturns etc. Reciprocity. This supposes that "we" is a powerful coalition of states that will act in concert and has enough economic clout to make these threats realistic. Do you have any example of such coalitions? OPEC comes to mind or the case of nuclear non-proliferation. What you are describing is what I understand under trade war. is there any difference in your view? It is also a nice circular logic by the way. What you say is that if you already have a powerful coalition then you can have a powerful coalition. Jacob:There is no environmental gain from preventing climate change? There is no short term environmental gain in reducing the emission of CO2 as it is not a pollutant. whether there will be a long term environmental gain in a hundred years say, is a matter of debate. e.g. germany's efforts will cost billions of euros and would reduce the temperature by less then 0,2 defrees in a hundred years. I wonder if you can sell this to voters. Jacob:I meant security in terms of not being dependent on imported oil, what do you mean by 'energy security'? Exacrtly the same thing. How about diversifying your suppliers ? Way cheaper then emission reduction I guess. Jacob:Isn't it amazing how nature always beats humans in ingenuity? Yes indeed, but I am afraid it is irrelevant to our discussion. Jacob:Let me reiterate: should anything be done to prevent climate change? I honestly do not know. All I know is that there is a large risk of proposing the wrong solutions with the idea that we have to do something. Economic war would be one such - and you seem to have no other solutions
120087. Chris G at 23:42 PM on 4 May 2010
        What causes Arctic amplification?
        Re: Arkadiusz Semczyszak #23 "Conclusion. As Frank said - it's energy imports determines the current scale and pace of rising temperatures in the Arctic. " We are talking about temperature anomalies in the arctic that are greater than temperature anomalies globally. That is, there is an increase in the arctic that is above and beyond what is happening globally. What mechanism would amplify the amount of energy going into the arctic from the rest of the globe when the arctic is relatively warmer than it has been?
120088. Arkadiusz Semczyszak at 22:31 PM on 4 May 2010
        What causes Arctic amplification?
        Riccardo OK. Agreed. However, the work of Simmonds & Screen 2010 contains important conclusions. For example, such as the proposal: "The findings reinforce suggestions that strong positive ice–temperature feedbacks have emerged in the Arctic, increasing the chances of FURTHER RAPID warming [?!] and sea ice loss, ..." If this is: THC-AMO (mainly), the the conclusion is hasty. Each methodology as the "older" and "younger", must be based on earlier findings - the results. Also, methods of measurement. E.g.: Alekseev et al., 2008, Arctic Sea Ice Data Sets in the Context of Climate Change During the 20th Century. - "September ice extent in the majority of the Siberian Arctic seas and in the Barents Sea reveal rapid shrinking during Arctic warmings in the 1920–1940s and 1990s. Significant correlation between surface air temperature and ice extent occurs in summer months with maximum in June under the influence of June maximum solar irradiation, and amplified by heat advection in the atmosphere and ice extent anomalies in the previous months. The relationship between variations of winter air temperature and ice extent is weaker because winter ice extent anomalies depend on air temperature anomalies as well as on the area occupied by a freshened upper layer. Good agreement between variations of the sum of summer air temperature in the marine Arctic and sea ice extent in September is found (correlation coefficient is 0.85)."
120089. Riccardo at 21:14 PM on 4 May 2010
        What causes Arctic amplification?
        Arkadiusz Semczyszak, what the paper under discussion does is to put current beliefs into question by using a different reanalysis and a different point of view. Just reaffirming older methodologies without critical comparison does not bring us much further ahead.
120090. Arkadiusz Semczyszak at 19:08 PM on 4 May 2010
        What causes Arctic amplification?
        Work Screen & Simmonds 2010, is so short - a rather fundamental conclusions. Its advantage, however, is a references. But whether the writers really benefited from - such as - this work: Chylek, P., Folland, C. K. & Lesins, G. Dubey, M. K. & Wang, M. Arctic air temperature change amplification and the Atlantic multidecadal oscillation. Geophys. Res. Lett. 36, (2009); ? "Analyzing temperature records of the Arctic meteorological stations we find that (a) the Arctic amplification (ratio of the Arctic to global temperature trends) is not a constant but varies in time on a multi-decadal time scale, (b) the Arctic warming from 1910-1940 proceeded at a significantly faster rate than the current 1970-2008 warming, and (c) the Arctic temperature changes are highly correlated with the Atlantic Multi-decadal Oscillation (AMO) suggesting the Atlantic Ocean THERMOHALINE CIRCULATION is linked to the Arctic temperature variability on a multi decadal time scale." Recall it: Chylek et al. 2006 - Greenland warming of 1920–1930 and 1995–2005; write that instrumental measurements indicate a large and rapid heating of the coast of Greenland in the decade of 1920. The average annual temperature has risen when the 2 to 6 degrees C in less than 10 years. "Temperature increases in the two warming periods are of a similar magnitude, however, the rate of warming in 1920–1930 was about 50% higher than that in 1995–2005." This rapid increase in temperature, while CO2 emissions to the atmosphere was 9-fold lower than in 2003 (Marland et al., 2006) speak of a natural cause of such a powerful warming. The same is here, only :http://ocean.am.gdynia.pl/p_k_p/pkp_19/Marsz-Stysz-pkp19.pdf "... the STRONG CORRELATION between the sea surface temperature (SST) in the region of the Gulf Stream delta and anomalies in surface air temperature (SAT) in the Arctic over the period 1880-2007. SEA ICE MAY EITHER INCREASE OR LIMIT THE HEAT FLOW FROM THE OCEAN TO THE ATMOSPHERE." "THE GENESIS OF THE 'GREAT WARMING OF THE ARCTIC' IN THE 1930S AND '40S IS THE SAME AS THAT OF THE PRESENT DAY." Really worth reading the two works. Are long and ... full of very interesting calculations - in contrast to the Screen & Simmonds 2010, but ... Marsz, also 2009 but by: Present warming - oceanic climate control; said: "Changes in SST in the Sargasso Sea, explains about 70% of the variability of SAT anomalies in the NH in the period 1880-2008 and 68% of the variability of global SAT anomalies [...]. In times of growth of SST in the Atlantic and North Atlantic sea sector of the Arctic, associated with INTENSIFICATION of the INTENSITY of THERMOHALINE CIRCULATION [!], there is an increase in air temperature in the NH. This increase is particularly strong in the higher latitudes - the Arctic and temperate zone." And I'll be back again also to FIG 11 - maps from this work: K.E. Trenberth, J. Fasullo, L. Smith, 2005: Trends and variability in column-integrated atmospheric water vapor. Climate Dynamics 24: 741–758; The largest increase in humidity over the past decades, we see it is in a place where the return of energy by the Gulf Stream ... Here the difference - in relation to the whole Arctic - is significant. The largest increase in humidity over the past decades in a place where we see the return of energy by the Gulf Stream ... Here the difference - in relation to the whole Arctic - is significant. The balance of energy resulting from the local greenhouse effect caused by water vapor - "positives" are often strongly underestimated. Conclusion. As Frank said - it's energy imports determines the current scale and pace of rising temperatures in the Arctic.
120091. SoundOff at 14:15 PM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        Arctic Oscillation, when very negative, as it was this past mid winter, produces extreme cold spells east of the Rockies, over Europe and eastern Asia. That’s exactly what we saw in January & February. The mild winter in most of Canada would be better explained by the the recent El Niño. NSIDC - Effects of the Negative Phase of the Arctic Oscillation
120092. philipm at 14:12 PM on 4 May 2010
        Skeptical Science talk at University of Qld on May 7
        I am at UQ (though not in something climate related). I hope I can catch up with you when you are here. I have a talk titled "Sceptical of the Sceptics" that I give sometimes. It's great to have material like yours to point people to. How about allowing the ice cubes to drift past while you wait for questions?
120093. philipm at 11:55 AM on 4 May 2010
        Skeptical Science talk at University of Qld on May 7
        John, great to have you at UQ. You should get a good audience. RSVP: check out my blog where I examine AMSU-A satellite data for the near surface layer since 1999. There is no known natural cause for a sharp upward trend over that period. We are coming out of a deep solar low that someone in The Australian little more than a year ago told us presaged an ice age, and our current position vs. ENSO should be the end of the cooling phase before the negative SOI phase a few months back results in warming. So what do I find? Over the first 4 months of the year, vs. the same period for the last 11 years, there's a warming trend of 5.8K per century. If humans aren't causing that, tell us what is. But be quick, because it's pretty damn worrying. Now switch to channel 9, 17km altitude, plot the 20 year average and all years. You will find every year 1999-2010 is well below the 20-year average. There is clear space between the average and the other curves. The only known mechanism that causes troposphere warming and stratosphere cooling is an increased greenhouse effect (specifically well-mixed gases like CO_2 -- water vapour can't do this, because its concentration is so low in the upper atmosphere).
        Response: Phillip, are you based at UQ? Thanks for the link to your blog post - we seem to be cut from the same cloth because I've been geeking out over the UAH satellite data and SOI data on a semi-regular basis (every couple of days, I have a peek) - currently, I've included the latest UAH screengrab in my slideshow but I may drop it as the talk is getting a little bloated (sadly, I don't think I'll be able to fit in my Greenland ice cubes).
        
120094. johnd at 11:28 AM on 4 May 2010
        What causes Arctic amplification?
        doug_bostrom at 09:56 AM, predictions are one thing, observations are another, with many predictions based on such observations as your linked article indicates. However understanding the physical mechanisms involved is another thing, and as in the article, scientists are just beginning to study some of those physical mechanisms. As an example, despite most CFC's being released in the NH, the ozone hole is generally over the South Pole. This thought to be because the ozone layer over the Arctic stays warmer by about 10 degrees than the that over the Antarctic. That is what happens and is measured and accounted for, but is there any understanding of why it is so? Is it the surface climate changing conditions in the stratosphere, or vice versa? What is not happening at one pole may be of as much importance as what is happening at the other, such being more likely to be revealed more by developing understanding of said physical mechanisms. It seems to me that in many cases the cart is before the horse, with assumptions being made simply because data correlates more so than an understanding of why it correlates, or if even relevant.
120095. Ned at 10:53 AM on 4 May 2010
        Why are there fewer weather stations and what's the effect?
        Berényi Péter, you are once again making very strong assertions based on a rather poorly conceived analysis. I applaud your interest in trying things out for yourself, but you really ought to put a little more effort into understanding what other people have done first rather than just leaping to the conclusion that they're wrong. As far as I can tell, your analysis completely ignores the spatial distribution of stations, which makes any conclusions essentially worthless. Tamino, Zeke Hausfather, Ron Broberg, and the other bloggers who have worked on this (Nick Stokes at moyhu.blogspot.com, Joseph at Residual Analysis, the Clear Climate Code team, etc.) all correctly understood that you can't just look at nonspatial averages of station anomalies. They all implemented some form of spatial gridding. The fact that temperature trends are spatially autocorrelated over long distances means that a gridded analysis will be robust to changes in the station population that would bias the trend in a more naive, lumped analysis. The scenario you've constructed is not a good match for reality.
120096. Doug Bostrom at 09:56 AM on 4 May 2010
        What causes Arctic amplification?
        Johnd, it sounds as though you're not familiar with predictions concerning the response of each hemisphere to an increasingly deranged energy budget. Here's a helpful summary incorporating reasonably recent findings.
        
120097. Riccardo at 09:54 AM on 4 May 2010
        What causes Arctic amplification?
        Frank, "transfer of heat from summer to winter" this happens all the time and will continue to happen untill there will be some ice around there. It's just heat capacity and latent heat at play, they both tend to stabilze temperature. But these heat fluxes can be pushed one way or another by a change in ice volume and extention. I can't see any big surprise here. What is new in the paper is its relative amount with respect to the atmospheric flux. But as always happen with cutting edge research, it might well not be the last word.
120098. Pete Dunkelberg at 09:43 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        # 5 Soundoff "This anomalous weather must be credited to the recent El Niño, ...." Think Arctic Oscillation.
120099. Frank2396 at 09:27 AM on 4 May 2010
        What causes Arctic amplification?
        Mspelto: Serreze 2009 was interesting. My point was that transport of energy from air to ice or water is controlled by the temperature differential between the source and sink for energy. How can increased transported of energy be responsible for a lack of temperature rise before some rise has occurred? On the other hand, once the ice cover is gone, surface air temperature will certainly be moderated by ocean temperature and ocean temperature is buffered by melting of nearby sea ice. I completely agree that increased open water in fall will lead to the ocean warming the air for longer than usual in autumn, but I don't believe this phenomena applies to winter. Videos show that ice coverage in the Arctic Ocean has reached equilibrium by early December and that most of the increase in sea ice coverage in winter occurs south of 70 degN (and isn't included in Screen's calculations). These event appear to be too far south to be the cause of warming at 85-90 degN. Figure 1 in Serreze shows that future Arctic Amplification is projected to be maximal near the summer solstice and minimal near the winter solstice. If these changes are driven by changes in sea ice - as Screen asserts - they should be maximal in the fall and minimal in the winter and spring - when changes in sea ice are occurring far away. If changing ice-albedo is the most critical factor in temperature change, that should be maximal when insolation is maximal. Riccardo suggests that there is a bigger effect in the winter because the difference between ocean and air is greatest in winter. As the ice at 85 degN thickens, energy is transferred through the ice cover to the air. 334 J/kg*917 kg/m^3 = 3*10^8 J/m^2 per meter of ice frozen. If thinner sea ice means that an addition meter of sea ice more is melting and freezing every season (180 days), the heat flux amounts to +20 W/m^2 (+5 degK at 250 degK)the winter and -20 W/m^2 (-4 degK) in the summer. If Screen had data showing that an average of 1 additional meter of sea ice was melting and refreezing every year at 85 degN compared with two decades earlier, he would have a mechanism for a 2 degC/decade rise in temperature that depends on sea ice. Without mechanistic details, he is simply engaging in undisciplined speculation about possible reasons for correlation. (Notice that a discussion of mechanism directs attention away from changes in sea ice coverage to changes in the thickness of sea ice melted and refrozen each season. "Arctic Amplification" driven sea ice by Riccardo's mechanism turns out the be simply a transfer of heat from summer to winter, amplifying global warming in the winter and negating it in the summer.) Figure 1 in Serreze shows that future Arctic Amplification is projected to be maximal near the summer solstice and minimal near the winter solstice. If these changes are driven by changes in sea ice - as Screen asserts - they should be maximal in the fall and minimal in the winter and spring - when changes in sea ice are occurring far away. If changing ice-albedo is the most critical factor in temperature change, that should be maximal when insolation is maximal.
120100. johnd at 09:23 AM on 4 May 2010
        What causes Arctic amplification?
        I understand that this topic deals specifically with the Arctic, but to be put into perspective with regards to Global warming, then should it not be compared to what is happening concurrently at the Antarctic, or perhaps more accurately, what is not happening at the Antarctic? The average temperatures and trends of each hemisphere are very different with an obvious warming bias in the northern hemisphere and closer to no change in the southern hemisphere. Warming due to CO2 is supposed to be global but if each hemisphere, and each polar region are examined individually, then obviously there are other factors to be considered, like long term cycles that will reverse over time. Certain factors may be in play in the Arctic to produce amplification, but what is happening at the Antarctic that either enhances or offsets them that will be reflected in the global situation?

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