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Comments 120051 to 120100:

120051. 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?
120052. 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!''
120053. 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...
120054. 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.
120055. 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?
120056. 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...).
120057. 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."
120058. 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.
120059. 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.
120060. 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.
120061. 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.
120062. 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.
120063. 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.
120064. 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.
120065. 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?
120066. 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.
120067. 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.
120068. 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?
120069. 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
120070. 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?
120071. 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)."
120072. 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.
120073. 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.
120074. 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
120075. 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?
120076. 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).
        
120077. 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.
120078. 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.
120079. 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.
        
120080. 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.
120081. 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.
120082. 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.
120083. 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?
120084. Riccardo at 08:21 AM on 4 May 2010
        Where is global warming going?
        suibhne, infrared photovoltaic detectors work like photovoltaic solar panels and could in principle be used to produce electricity. Whatever the type of IR detector used, radiation from the atmosphere can, and indeed is, measured. It's energy, no doubt.
120085. suibhne at 08:10 AM on 4 May 2010
        Where is global warming going?
        KR You made my point for me, the "back radiation" cannot do any work. This means it cannot be described as heat. I see you followed my version of the Alamo at Deltoid. Two reasons for the pause in my contributions; 1. The article by H=>Z has still not been published. 2. While you can have a rational discussion with Sylas, Arthur Smith and Stu there are others on that site who simply want to hurl abuse behind the safety of the internet. Thank goodness for a site like Skeptical. While I have not fundamentally changed my position it is not the same as it was say two months ago. All the best.
120086. KR at 07:49 AM on 4 May 2010
        Where is global warming going?
        To clarify my previous comment: the EPA document, Volume 3, Comment 3-45 and Response 3-45 on page 38 is a direct response to the issues in Gerlich and Tscheuschner (2009).
120087. KR at 06:50 AM on 4 May 2010
        Where is global warming going?
        suibhne, take a look at the EPA response, particularly Volume 3, Comment 3-45 and Response 3-45 on page 38. You're welcome to take it up with the EPA, but the vast scientific consensus is that G&T are full of, um, hot air... As to the 324 back radiation discussion, AGAIN!!! - I would love to put that energy to work, preferably in my car. Unfortunately, that's part of the sea-level radiative balance, and there are no cold sinks to divert it to, no opportunity to extract work from it. See the definition of "work", under "Zero work", for this situation. 'Nuf said, suibhne. We went around and around on this under the "Is CO2 a pollutant" thread, you've had the same argument on other blogs, and in each case you've repeatedly refused any physics not from G&T, changed the subject, or just left the discussion midstream when it became clear that nobody found your arguments persuasive. You seem to have a basic misunderstanding of 'zero work' situations of steady state systems, and repeated raise issues of 'work' when there is zero net energy flow. That's really a freshman physics error, and if you don't/won't get it, there's nothing anyone here can say to you... My apologies for the harshness of my reply; I'm more than willing to have a discussion, but you haven't shown a willingness for that. It's quite frankly not worth my time.
120088. Chris G at 05:31 AM on 4 May 2010
        What causes Arctic amplification?
        Frank's post has been pretty well covered already, but I'll add, or restate, a couple of points in ways that I think are simpler. Others can correct me if I'm too far off. We are talking about an amplification of warming. Frank seems to be proposing some mechanism that moves more heat into the arctic region when the region is warmer, than it did when the region was relatively cooler. That is counter-intuitive for me. The primary factor we are looking at is ice loss and regain. Frank's post is all about temperature, but in a phase change, there are large changes in energy with little or no change in measured temperature. When ice melts in the summer, there can be large changes in energy with very little change in temperature. This energy is released as the water freezes, and we see a positive temperature anomaly, in the fall/winter, compared to historical points when the water was already frozen in that place and time of year.
120089. suibhne at 05:24 AM on 4 May 2010
        Where is global warming going?
        KR Yes Ive read Arthur Smiths paper and still prefer G&Ts version of reality. One thing for me sums up the departure of AGW advocates from reality is 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.
120090. Philippe Chantreau at 05:06 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        I've dealt with METARs a lot during my days as a pilot and flight instructor. They are automated reports from stations that rely on sensors. Pilots learn to not rely too extensively on reports from unmanned stations, especially for some indications. The station "looks" at a rather small extent of sky, so sky cover may be different from reality. Visibility is ground visibility (normally measured in a direction parallel to the runway axis from the station location) and may not be the same as the slant range visibility that matters when looking for the runway treshold in an instrument approach. Some stations have a precipitation discriminator (type2 if I recall, it usually figures in the remark section of the aviation METAR), others don't. Even the ones that have it can experience temporary malfunctions of the sensor. Some types of precipitation are more likely to "confuse" the sensors, like heavy fog that falls as very fine drizzle (especially below freezing), or freezing rain. The stations are a great tool, but they're only robots and ill-equipped to give an accurate rendition of what goes on in complex weather situations. You could have a cold layer near the ground just a couple of hundred feet thick, with layers of various and higher temperatures as altitude increases, leading to all sorts of variations in precipitation. What was described by Geo-Guy certainly reflects one of these types of situations evolving over time, seen from the ground. It's all weather. I would not put too much trust in such minute amounts of precip as were reported in the METARs linked by John and other posters.
120091. KR at 04:56 AM on 4 May 2010
        Where is global warming going?
        Take a look at the Arthur Smith paper. I've spent a number of hours on G&T (sigh - time I'll never get back, time that would have been better spent with a decent beer); Smith's paper is only 9 pages and very clear. G&T say that there is no such thing as a radiative greenhouse effect. They are quite simply wrong. The magnitudes and numbers for heating via LW radiation trapping and total radiative imbalances are well established by numerous sources; not much I can add there.
120092. suibhne at 04:38 AM on 4 May 2010
        Where is global warming going?
        KR On G&T ....G&T's major confusion seems to be about "heat radiation", aka thermal radiation, emitted by anything above 0K...... I think G&T have been misunderstood on this point. They say radiation can go from a lower temperature body to a higher temperature body. However they say HEAT cannot go from a lower temperature body to a higher temperature body. This is simply stating the "bleedin" obvious in terms of standard thermodynamics.
120093. suibhne at 04:29 AM on 4 May 2010
        Where is global warming going?
        KR On the thought experiment. Like all these gross simplifications it is fetched pretty far. But then so are calculations about the Earths atmosphere that ignores Oceans and so on. I thought it would be interesting though to get a simple value for the Earths thermal capacity or the amount of energy required to increase its temperature by one degree c. A slightly more realistic one for the Oceans gives 30years for a rise of one degree. Assumptions 10% imbalance in radiative equilibrium and using the value of surface radiation 168 w/m2. Both calculations show a large value of thermal inertia.
120094. Phila at 04:08 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        #4 CoalGeologist "It is a "double edged sword" to use single events as providing proof that AGW is occurring, when certain other rare "events" such as this past cold, snowy winter in the eastern U.S. could potentially be cited as proof that AGW is a "hoax"." Without condoning citing single events as "proof" of AGW, I think the difference is that cold, snowy winters are consistent with AGW. While it may be an error to make too much of, say, a heat wave, it's an error of an entirely different type to claim that if it gets cold in the Northern Hemisphere in winter, then AGW must be a hoax. One results from confusion; the other is an attempt to produce it.
120095. iskepticaluser at 03:48 AM on 4 May 2010
        What causes Arctic amplification?
        A recent technical paper, entitled An Initial Estimate of the Cost of Lost Climate Regulation Services Due to Changes in the Arctic Cryosphere and sponsored by the Pew Charitable Trusts, provides another warning of just how strong the feedback effects of a melting arctic may already be. From the summary: “. . . the combined heating effect from the loss of sea ice and snow and the increased release of methane from permafrost in 2010 is roughly equal to releasing an additional 3 billion metric tons [my emphasis] of carbon dioxide into the atmosphere. For comparison, this equals 42 percent of current annual U.S.emissions of greenhouse gases.”
120096. KR at 03:32 AM on 4 May 2010
        Where is global warming going?
        In regards to G&T's more outrageous points, I find Arthur Smiths rebuttal quite clear. Even a single layer of IR scattering (absorbance/emisison) atmosphere can be very simply shown to produce a greenhouse effect, and a more realistic thick layer with temperature gradients and convection will be even more effective. G&T's major confusion seems to be about "heat radiation", aka thermal radiation, emitted by anything above 0K. In section 3.9.3 their misunderstanding (amazing if it isn't intentional) is quite evident, and leads to their claim that heat radiation and energy flow balancing somehow contradicts the 2nd law of thermodynamics. This is a clear attempt on their part to confuse heat flow (net energy changes) with heat radiation.
120097. Ron Crouch at 03:24 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        I had hoped to do this all in one post but there were some technical difficulties with the Environment Canada website. #10 Berényi Péter Your last point surrounding the Metar report for Alert on Apr 3, 2009. Although the Metar report clearly states rain with no accumulation it is unsupported by either hourly reports from Alert airport which only reports ice crystals, or Alert Autonomous which shows a trace of snow.
120098. Geo Guy at 03:13 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        Interesting post and just goes to show that climate doesn't always fall into neat organized categories. In 1973 I was working in Uranium City in northern Saskatchewan (north shore of Lake Athabasca). At 8:00 pm on New Year's eve (73-74)it was -40 F (we hadn't switched to metric then). When we left the festivities at about 12:45 am New Year's day, the temperature had sored to +40F! By 10:00 am later that morning it had dropped to about - 10F. I am sure there are many other oddities in the weather, especially in areas that are isolated as in Northern Canada, that go unreported. Certainly rain in April is not that far fetched - it may have happened 20 km away from the weather station in the past but simply went unreported. Having worked in isolated areas of Canada in the past I can assure you that things such as thunder showers in winter happen, although not that frequently. Calgary (where I currently live) has had significant snow falls in August and golf weather in January, all which seem to be linked to where the jet stream is located. I guess what this can tell us is climate and climate change is a multi-faceted process contingent not upon one single parameter but rather it is the result of the interaction of many parameters.
120099. Doug Bostrom at 02:45 AM on 4 May 2010
        Skeptical Science talk at University of Qld on May 7
        RSVP points out that certain organisms with large populations and short reproductive cycles can benefit in certain circumstances from a change of climate, usually by chewing through a local ecosystem ill-prepared for fast changes. From this we are to derive comfort. Thank you, RSVP. I will welcome my case of West Nile encephalitis or whatever little critters may adapt their way into my province as Good News.
120100. Ron Crouch at 02:34 AM on 4 May 2010
        Rain in the Canadian High Arctic in April?
        My apologies the link to the daily data for Isachsen for June 1975 should point here.

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