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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 106951 to 107000:

  1. The sun upside down
    My link didnt work, try this one
  2. The sun upside down
    giancarlo at 02:22 AM What this paper is suggesting, if these trends are not anomalous, is that the solar effects on the stratosphere maybe what is driving the cyclic climatic responses to the solar cycle, Riccardo has linked two papers on the subject at 19:12 PM on 13 October, 2010 , and i also linked one at 09:15 AM on 12 October, 2010 . But the stratospheric effects themselves are not new, Ramanthan and Dickenson 78 This could potentially be far reaching, if the dynamical responses from stratospheric cooling from UV have been having a greater effect than believed, it could also mean that anthropogenic O3 destruction, and co2 cooling of the stratosphere could also be having, uncontributed effects. This is wild speculation, but thats what blogs are for ;-)
  3. The sun upside down
    giancarlo no one could have thought in terms of what if it's true. There's no answer at the moment to the question of how to explain much of what we know about the solar influence on climate. My guess is that people will look harder at the impact of UV, apparently the only thing left in phase with the total solar irradiance (TSI). But it's just a guess, I'd better say I don't know. The TSI has been directly measured only in the satellite era. There are proxy for it, sun spots, radio frequency emission, magnetic field, radioactive nuclei formation, etc. None of them has spectral capabilities, it all stands on what we know about the link between the proxy and the spectral changes of the sun irradiance. The answer to the spectral changes issue will probably come from future measurments more than from reconstructions of the past.
  4. Explaining Arctic sea ice loss
    @RSVP: "this difference of opinion would be tolerable if humanity didnt have to make some important choices." Actually, humanity needs to wean itself of fossil fuels anyway. There is tremendous economic opportunity in renewable energy. Why do you think China is already becoming a leader in that area, while the US lags behind due to the Oil interests muddying the debate?
  5. Antarctica is gaining ice
    Actually Slimboy it would be better if you sourced your entire comment. You do a back-of-the-envelope calculation, lay out a bunch of speculation and expect to be persuasive? Not up to snuff.
  6. Antarctica is gaining ice
    Slimboy, how about redoing the last paragraph of your comment except this time w/sources?
  7. Explaining Arctic sea ice loss
    RSVP this CO2 affair is really not so much a matter of population dynamics as it is the unfortunate physical dynamic effects of our quite naturally seizing and using what appeared to be a eerily wonderful and even anodyne tool, one with several faces, a substitute energy source that I'll note in many places helped somewhat to arrest our breathtaking destruction of forests. Lately we've learned that certain physical side-effects of using this tool are incompatible with the systems over which our culture is draped. Now we need another substitute energy source. This is just part of growth, it's inevitable, really, and we should actually welcome it. The question is, will we use the ever-shrinking and increasingly hazardous lever we found in the 19th century to lift us to where we need to be in the 21st century? A topic for another thread, I think...
  8. Mikko Virtanen at 02:47 AM on 16 October 2010
    Climate scientists respond to Monckton's misinformation
    "Why wasn't this done years ago?" I'd like to remind you of the existence of Complaint to Ofcom Regarding “The Great Global Warming Swindle” from 2007, which was "organised by three concerned citizens and was co-authored and peer reviewed by a group of 20 people. Some of the world’s most respected and experienced climate scientists, including former IPCC chairs and co-chairs, were involved, as were distinguished experts in epidemiology, entomology, economics, the media and renewable energy." As we know, “The Great Global Warming Swindle” was full of denier arguments, and this response goes through the film line by line, graph by graph, lie by lie. I still consider it a very nice resource. It's great that there is this new effort, but the old one is still worth remembering too!
  9. The sun upside down
    Hi evrybody, I am Giancarlo, this is my first post. Even though I am an astronomer, and I worked, among the other things, on chromospheric activity in solar-type stars, there are many things on the topic I have no idea of, I hope my question is not too naive. If the data from the satellite confirm the "upside down effect" on the long period of time, that would be quite puzzling, wouldn't it? How could you explain the results by Solanki, of a correlation between cycle-averaged solar activity and the temperature? I read somewhere in this website that the global warming of anthropic origin characterizes itself as the time in which solar energy input and earth temperature start following different trends, constant the former and increasing the latter. But before a few decades ago the two quantities were closely related. Did I get it right? How did they measure the solar energy input in the optical range in the past time? And how could you explain the fact that, on top of the golobal warming trend, there is a cycle that closely match the solar activity cycle? http://www.skepticalscience.com/solar-cycles-global-warming.htm In this case, there would be a delay in the effect that solar energy has on terrestrial temperature. This was also mentioned in #9
  10. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    Looking at the Morano post puts me in mind of the Most Used Skeptic Arguments - it's like a rundown of the most common denials. * "It's not warming" * "Climate has varied before" * Stating that Greenland survived the last interglacial without noting that even a fraction of Greenland melting would cause considerable sea rise * Strawman arguments about 20ft theoretic rises from complete melting that nobody is predicting * "Models are unreliable" Not to mention the poor scholarship from Mörner and the discredited Soon/Baliunas article, as Robert Way points out.
  11. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    Berényi - Never mind, I see that you've just copied the Morano references to this thread.
  12. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    I'm sure he had reasoning to feel the way he did but lets be honest here, you cited Soon and Baliunas (2003) eventhough the aforementioned paper is widely discredited and resulted in the resignation of half the editorial board because it was published. Is this the evidence that Morano was using to support his thesis? Awful convenient of you to bring up that study.
  13. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    Berényi - That's 15 references, from all over the place; the AR4 SYR Synthesis report (known to be underestimates of current conditions), Climate Research and E&E papers by Soon arguing against the hockey stick (my apologies, I cannot take Soon or those two journals seriously based on their history), the Howat et al Science article indicating higher than expected variability in Greenland glacier speeds, the Monaghan et al Science article indicating that Antarctic precipitation has not increased as expected (bad news for Antarctic mass balance, quite frankly), and so on. That's quite a shotgun blast of articles. Could you perhaps indicate what they point to? How they support Morano's statements? Because they seem to be all over the map to me, and presenting links without commentary isn't all that useful.
  14. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    Marc Moreno's usage of the term "global warming" is representative of a frequent and intentional effort by AGW Denialists to confuse and obfuscate the issues surrounding the current, ongoing episode of warming, which is interpreted to be largely anthropogenic in origin. It makes it sound as if the present warming is no different from episodes of warming that have occurred in the Earth's past. Yes, Earth's climate has changed significantly in the past in response to natural processes; however these changes generally occurred over much longer time frames, and although they were evidently enhanced by increased atmospheric CO2 (in Pleistocene to Recent glacial cycles, at least), they were not initiated by CO2. Greenland temperatures warmed during the mid-Twentieth Century, but again, this was evidently not driven by anthropogenic GHGs. The present episode of warming, which is popularly referred to as "global warming" (a term which the IPCC neither uses nor defines) is being driven largely by the build-up of anthropogenic greenhouse gases in the atmosphere. As we can potentially control these, we can potentially influence ongoing climate change. At the same time, the title of the current discussion, which refers to "stopping" climate change, is open to valid skeptical criticism. Even if we can successfully reduce the impact of anthropogenic forcing on climate, this will not eliminate the effects of natural forcings, which will continue to play a role, albeit over a much longer time frame.
  15. Explaining Arctic sea ice loss
    @ RSVP at 03:52 AM on 15 October, 2010 Please put a thermometer in a glass of ice water, stir continually, and record the temperature every minute. Plot the temperature over time. The temperature will stay right at freezing, neither cooling nor warming, until the ice is gone. I'm not sure that I'm here to teach you basic physics. Also, please try to understand the difference between Doug's statement, that CO2 is what is changing now that is driving the changes observed in the sea ice, and your statement, and your statement that in order for that to be true, the changes should be symmetrical. You can probably find more information under the topic on the left, 'Antarctica is gaining sea ice'. Also, feel free to use Google Scholar and search for 'antarctic sea ice'.
  16. Berényi Péter at 01:05 AM on 16 October 2010
    Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    Posted by gpwayne on Friday, 15 October, 2010 at 14:59 PM Climate change skeptics like Marc Morano employ gross exaggeration to dismiss or diminish the potential disruption that climate change is likely to bring about. In the Inhofe EWP press blog, Morano made much of this statement [...] That blogpost is more than three years old, dated 9:39 AM ET, July 30, 2007. Latest Scientific Studies Refute Fears of Greenland Melt Posted By Marc Morano What he says is not entirely unsupported. For the sake of fairness you could at least dig up references from that post or peer reviewed literature backing them.
    1. Annals of Glaciology Volume 46, Number 1, October 2007 , pp. 209-214(6) DOI: 10.3189/172756407782871558 20th-century glacier fluctuations on Disko Island (Qeqertarsuaq), Greenland Jacob C. YDE & N. Tvis KNUDSEN
    2. GEOPHYSICAL RESEARCH LETTERS VOL. 33, L11707, 5 PP., 2006 doi:10.1029/2006GL026510 Greenland warming of 1920–1930 and 1995–2005 Petr Chylek, M. K. Dubey & G. Lesins
    3. Science 11 November 2005: Vol. 310. no. 5750, pp. 1013 - 1016 DOI: 10.1126/science.1115356 Recent Ice-Sheet Growth in the Interior of Greenland Ola M. Johannessen, Kirill Khvorostovsky, Martin W. Miles & Leonid P. Bobylev
    4. JOURNAL OF GEOPHYSICAL RESEARCH VOL. 111, D11105, 2006 doi:10.1029/2005JD006810 Extending Greenland temperature records into the late eighteenth century B. M. Vinther, K. K. Andersen, P. D. Jones, K. R. Briffa & J. Cappelen
    5. Science 16 March 2007: Vol. 315. no. 5818, pp. 1559 - 1561 DOI: 10.1126/science.1138478 Rapid Changes in Ice Discharge from Greenland Outlet Glaciers Ian M. Howat, Ian Joughin & Ted A. Scambos
    6. Science 6 July 2007: Vol. 317. no. 5834, pp. 111 - 114 DOI: 10.1126/science.1141758 Ancient Biomolecules from Deep Ice Cores Reveal a Forested Southern Greenland Eske Willerslev, Enrico Cappellini, Wouter Boomsma, Rasmus Nielsen, Martin B. Hebsgaard, Tina B. Brand, Michael Hofreiter, Michael Bunce, Hendrik N. Poinar, Dorthe Dahl-Jensen, Sigfus Johnsen, Jørgen Peder Steffensen, Ole Bennike, Jean-Luc Schwenninger, Roger Nathan, Simon Armitage, Cees-Jan de Hoog, Vasily Alfimov, Marcus Christl, Juerg Beer, Raimund Muscheler, Joel Barker, Martin Sharp, Kirsty E. H. Penkman, James Haile, Pierre Taberlet, M. Thomas P. Gilbert, Antonella Casoli, Elisa Campani & Matthew J. Collins
    7. IPCC Fourth Assessment Report Climate Change 2007: Synthesis Report 3.2.1 21st century global changes Table 3.1. Projected global average surface warming and sea level rise at the end of the 21st century.
    8. The Holocene 12,1 (2002) pp. 49–58 DOI: 10.1191/0959683602hl519rp A mid-Holocene shift in Arctic sea-ice variability on the East Greenland Shelf Anne E. Jennings, Karen Luise Knudsen, Morten Hald, Carsten Vigen Hansen & John T. Andrews
    9. GEOPHYSICAL RESEARCH LETTERS VOL. 32, L17605, 4 PP., 2005 doi:10.1029/2005GL023740 One more step toward a warmer Arctic Igor V. Polyakov, Agnieszka Beszczynska, Eddy C. Carmack, Igor A. Dmitrenko, Eberhard Fahrbach, Ivan E. Frolov, Rüdiger Gerdes, Edmond Hansen, Jürgen Holfort, Vladimir V. Ivanov, Mark A. Johnson, Michael Karcher, Frank Kauker, James Morison, Kjell A. Orvik, Ursula Schauer, Harper L. Simmons, Øystein Skagseth, Vladimir T. Sokolov, Michael Steele, Leonid A. Timokhov, David Walsh & John E. Walsh
    10. GLOBAL WARMING Notes on Climate Change Syun-Ichi Akasofu
    11. Earth and Planetary Science Letters Volume 207, Issues 1-4, 28 February 2003, Pages 13-22 doi:10.1016/S0012-821X(02)01155-X Modern spectral climate patterns in rhythmically deposited argillites of the Gowganda Formation (Early Proterozoic), southern Ontario, Canada Gary B. Hughes, Robert Giegengack & Haralambos N. Kritikos
    12. Global and Planetary Change Volume 40, Issues 1-2, January 2004, Pages 177-182 Global Climate Changes during the Late Quaternary doi:10.1016/S0921-8181(03)00108-5 New perspectives for the future of the Maldives Nils-Axel Mörner & Michael Tooley
    13. CLIMATE RESEARCH Vol. 23: 89–110, 2003 Proxy climatic and environmental changes of the past 1000 years Willie Soon & Sallie Baliunas Energy & Environment doi: 10.1.1.124.3216 Reconstructing climatic and environmental changes of the past 1000 years: a reappraisal (2003) Willie Soon, Sallie Baliunas, Craig Idso, Sherwood Idso & David R. Legates
    14. Science 11 August 2006: Vol. 313. no. 5788, pp. 827 - 831 DOI: 10.1126/science.1128243 Insignificant Change in Antarctic Snowfall Since the International Geophysical Year Andrew J. Monaghan, David H. Bromwich, Ryan L. Fogt, Sheng-Hung Wang, Paul A. Mayewski, Daniel A. Dixon, Alexey Ekaykin, Massimo Frezzotti, Ian Goodwin, Elisabeth Isaksson, Susan D. Kaspari, Vin I. Morgan, Hans Oerter, Tas D. Van Ommen, Cornelius J. Van der Veen & Jiahong Wen
    Moderator Response: [Graham] Fine example of the Gish Gallop. And Soon and Baliunas, E&E - you have a fine sense of humour - at least, I hope that's your intention. As for 'fairness', as soon as Morano adopts such values, I'll be pleased to follow his example.
  17. An underwater hockey stick
    More hockey-sticks/statistics from Richard L Smith (Statistical and Applied Mathematical Sciences Institute, Research Triangle Park, N.C. and Department of Statistics and Operations Research, University of North Carolina, Chapel Hill). In this discussion, we use principal components analysis, regression, and time series analysis, to reconstruct the temperature signal since 1400 based on tree rings data. Although the "hockey stick" shape is less clear cut than in the original analysis of Mann, Bradley and Hughes (1998, 1999), there is still substantial evidence that recent decades are among the warmest of the past 600 years. The results support an overall conclusion that the temperatures in recent decades have been higher than at any previous time since 1400. On the other hand, none of the recent reconstructions shows as sharp a hockey stick shape as the widely reproduced Figure 3(a) of MBH 1999, so in that respect, critics of the hockey stick are also partially vindicated by these results.
  18. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    Hey, thanks for that comment boba10960. It will be interesting to see if that SLR estimate from Dutton's presentation (8-10 m) holds up. Re: the WAIS, there is evidence that it has collapsed during at least one previous interglacial (Scherer et al. 1998). The authors speculate that MIS 11 is a likely candidate but if global sea levels really were at +8-10 m during the last interglacial one would think that the WAIS would be the most likely source for the additional water. I don't think its extent is as well constrained as Greenland's is.
  19. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    There is a bit more detail about the Pleistocene history of the Greenland ice sheet in this post: The Past and Future of the Greenland Ice Sheet There is good evidence (from both ice cores and models) that (a) the ice sheet was smaller during the last interglacial [MIS-5e], but (b) it did not melt away completely. Otto-Bliesner (2006) shows the following modeled comparison of the extent of the ice sheet then and now: Modeled configuration of the Greenland Ice Sheet today (left) and in MIS 5e (right), from Otto-Bliesner (2006). The reduction in size of the ice sheet during MIS 5e probably added 3-4 m to global sea levels, which accounts for about half of the 6+ m total rise in sea levels during that interglacial (Alley 2010). For what it's worth, the Greenland ice sheet appears to mostly or entirely have disappeared during an earlier interglacial (MIS-11, around 400,000 years ago) that is considered to be the best analog for our current interglacial. I'm not sure whether the different extents of the ice sheet in MIS-11 vs MIS-5e was due to its longer duration (MIS-11 was a particularly long interglacial), warmer summers in Greenland, a combination of both, or something else.
  20. The sun upside down
    HumanityRules in my comment #26 you'll find two references about the impact of UV changes. We need to know how the solar spectrum varies and indeed we already knew a lot, though not all. This new paper open the possibility of some undected (occasional?) changes, but before using the word "probably" I'd read again the caveats I quoted.
  21. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    There were two relevant talks on this topic presented at the Tenth International Conference on Paleoceanography in San Diego last month. http://icp10.ucsd.edu/ First, I assume that "Earth’s last period of global warming" in Morano's quote refers to the last interglacial period about 125,000 years ago. The latest estimates place global average temperatures at that time about 2°C above today's temperature, so that period is very relevant conditions that lie ahead. This time period was the topic of the two presentations I refer to. One speaker (Dorthe Dahl-Jensen, Niels Bohr Institute, Copenhagen, Denmark) used results from all existing ice cores in Greenland to conclude that the amount of ice that survived the warmer conditions roughly 125,000 years ago was about half the current volume of ice. So, in this sense the Morano statement is correct, but the Greenland ice that did melt contributed about 3 to 4 meters of sea level rise. The second speaker (Andrea Dutton, Australian National University, Australia) presented evidence that eustatic (global average) sea level during the last interglacial period was 8 to 10 meters greater than today, rather than 5 to 6 meters greater, as previously thought. If both speakers are correct, then the simplest interpretation of their findings is that the west Antarctic ice sheet, which is much more sensitive to melting than the east Antarctic ice sheet, was almost completely gone during the last interglacial period. That is, global average warming of about 2°C, 125,000 years ago, led to the complete loss of the west Antarctic ice sheet and to the loss of about half the Greenland ice sheet. It will be very interesting to see if further research supports these findings.
  22. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    HR: Information on the negative mass balance trend of the East Antarctica ice sheet can be found here.
  23. Explaining Arctic sea ice loss
    RSVP #45 "Our difference lies in the assumed mechanism" You mean "hypothesised mechanism". And doug's hypothesis has much support, while yours has pretty much been chucked in the gutter, but being a zombie hypothesis, the so-called-climate-sceptics recycle ad infinitum in the hope that it will eat our brains!
  24. Explaining Arctic sea ice loss
    To doug_bostrom: I would not argue at all that the pace of change in the Artic is due to the effects of unprecedented human growth. Our difference lies in the assumed mechanism, and this difference of opinion would be tolerable if humanity didnt have to make some important choices.
  25. Explaining Arctic sea ice loss
    Thanks for the compliment, RSVP. The reason for the conclusion is the same as the requirement for the article; skeptics struggle to explain the demise of Arctic sea ice as a natural phenomenon. After a look at the latest research on the topic including Polyak's massive meta-analysis it appears quite clear that today's loss of ice is novel and related to anthropogenic CO2. The final paragraph is a brief summary of a brief article. There's no other way to say it, really.
  26. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    @johnd: you seem to be confusing ice ages with glacial periods. We are in fact still in an ice age, as ice exists on the globe. We are, however, in an interglacial period, i.e. one of the warm periods of the current ice age.
  27. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    It seems like you're first two paragraphs puts the rest of the article completely in the realm of speculation and fantasy. And then I was knocked a little sideways by that sudden jump from Greenland to global. Any evidence the EAIS is going anywhere? I hope it's not wrong to assume that with the 1% and 99% examples you were simply plucking numbers out of thin air? In relation to the bold statement at the bottom of your article it's worth considering that 1% isn't the lowest possible limit. How's about o.1% or even 0.0001%? I'm not saying either of these are relevant on any real world time scale but it's also possible that rates of melt maybe so low as to be NOT very disruptive as well.
  28. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    Defining an end (or start) to a glacial could likely be done by defining a limiting multiple for the pace of global warming (or cooling) exceeding the forcing from Milankovich cycles alone. This though would lead to extensive intermediate periods between 'stable milankovich climates', the current of which began by AGW. I've no reference for this though, as it seems too evident a definition, maybe no one has done that. An easy thesis subject for someone who wants to quarrel with the denialists for the rest of their existence?
  29. The sun upside down
    Just read the moderator response to #34. Hopefully these responses won't go the way of cloa513. At least some of this is on topic I think ;) 20.muoncounter Not with any wish to defend that guy he does qualify that statement by saying "in the DMI database". And that still doesn't really prove this is a dominant idea amoung sceptics. But you're right the title is mis-leading. The few times I've posted on WUWT have often been around Goddard ignoring the longer term arctic ice history in favour of describing short term conditions. 21.Daniel Bailey I find most of what Monbiot writes unpleasantly misanthropic myself. But there's a strange process going on with climate science journalists ATM. Richard Black was critisised on Joe Rohm's website, unnecessarily in my view. Revkin has been disowned (was that Rohm as well?). It strikes me as a dangerous process, alienating prominant voices in the media because they don't match one's own extreme position. It looks like the action of a zealot to me and counterproductive in building a consensus. If I was an warmist I'd be more concerned about Rohm than I would about the journalists. [sarc on]Apart from being in the pay of big oil of course [/sarc off] why would much of the criticism from the 'lukewarmer' climate scientists be around the poor handling of uncertainty by the IPCC? 22.Phila It seems perfectly reasonable to critise the overcertainty around theories based on the present incomplete data while at the same time demanding greater certainty presumably by getting some better data in the future. Given that CO2 is a GHG then it strikes me that AGW has to be considered as one explanation of what's been measured these past few decades but I don't think it's the only possible explanation. 23 Doug You seem to be ignoring the role of advocate-scientists in this process. Schmidt, Schneider, Hansen and many more (of course we shouldn't neglect those batting for the other side). These people choose to cross the boundary between scientist and messenger. They seem to break the rules you describe. What do you think their role is? Just as an example I can't find any strongly expressed caveats in this new paper which is making an extremely strong scientific statement about climate science in a very prominent science journal. What do you think should be the important caveats in this work? Or do you think there should be none? (the ealier vagueness was an attempt not to go OT, it hasn't worked.) 24.Riccardo So what would be the results on the rest of the climate system of affecting the stratosphere in a not negligible way? Now that we know about the variation in the spectrum it's probably not good enough just to look at TSI in order to see the impact of solar variation on the climate. We need to know how the solar spectrum is varying and how those variations interact to impact on climate. This paper just seems to describe some possible first order affacts (i hope that's the right use of the term). Would you agree with that?
    Moderator Response: Since we didn't stop the off topic discussion earlier, I'll let your concise (thank you) response stay. But everybody please take further off-topic comments to other threads.
  30. Skeptical Logic Can't Save Greenland Ice - for that you need to stop climate change
    Not exactly on topic, but none the less relevant in light of the statement referring to "the last period of global warming", is there any defined point at which it can be declared as the beginning of an ice age, or an ending? Would an ice age only be declared as having ended when all the ice sheets have melted? With still a considerable number of glaciers of immense size existing, are we still in fact in what would be defined as an ice age? When statements such as "the last period of global warming" or the last ice age are being used, there should be some criteria that defines ice ages so that it is clear whether the period being referenced is within an ice age or not.
  31. Explaining Arctic sea ice loss
    doug_bostrom #42 The article is well written, and should serve as a vehicle for further discussion. The last paragraph is an invitation for anyone who is'nt fully convinced that everything would go back to normal if the atmosphere's CO2 concentrations returned to their pre-industrial levels, or that this is what mainly caused this situation in the first place. On the other hand, if the link between CO2 and Artic melting is so conclusive and significant, why is this tossed in at the last minute?
  32. It's the sun
    Ken Lambert - my apologies, I was thinking about the UV issue (several orders of magnitude insignificance), which apparently wasn't being brought up. Too many threads... The greenhouse gas forcing is only 4-5 times the TSI forcing, and the TSI change is currently going in the opposition direction from the temperatures. Not an order of magnitude - I was off by a factor of two. But it's still 4-5x the TSI forcings! It's really, really not the sun. TSI changes have not correlated with temperature changes over the last 40 years, GHG forcing changes have. Unless you somehow disagree with this basic and quite provable point?
  33. The sun upside down
    cloa513 - what about the "99%" (you can make that any number by choosing your criteria) do you think is relevent to this discussion? There a physical limitations to how much of an unknown (say an unknown volcano) can be affecting an estimate (eg global heat flow). Perhaps you could comment further on a more relevant thread than one about the sun? How much certainty do you need by the way for your decision-making? We constantly make decisions in face of imperfect knowledge.
    Moderator Response: I deleted cloa513's comment because it was off topic for this thread. cloa513, please peruse the "Arguments" page to find a more relevant thread.
  34. Skeptical Science housekeeping: Comments Gluttony
    I'd be interested in seeing such a post too but he had best be prepared for the full vigorous shakedown of his analysis haha
    Response: I think that's what put him off doing the post. Talk about a tough crowd! :-)
  35. The CO2/Temperature correlation over the 20th Century
    Arkadiusz Semczyszak, Whether it is the opposite? It can be the opposite and it can be the way it is now. CO2 can act as a feedback and a forcing. This is pretty straightforward science.
  36. New temperature reconstruction vindicates ...
    Sorry Ned, off post a bit, I'll get back on track shortly. protestant at 00:30 AM on 15 October, 2010 In the above case (156) the simple "Excel" moving average function plots a mean for the previous 10 years. You are correct that a 10 year average centred on 2010 is currently impossible but this is not the point. You have rather conveniently ignored the mathematically valid statement on ENSO periods with regard to linear regression and then confused this with averaging in terms of appropriate period. On a time series like this, a trend will significantly change with end point choice, a running average will not. You simply cannot arbitrarily choose peaks or troughs for linear trend start/end points to support your argument, and you really do need to calculate a linear trend over something like 20 years to avoid severe bias from ENSO (or try to subtract ENSO index as commented above). You continue with the misconception about warming halting in 1998. How can you validate this? Look at the ten year running average in red (now +/- 5yrs), and the most recent 20 year trend in dark blue below. Both sailing straight through the 1998 peak, on an underlying upwards trend. Do you really claim flattening or halting? I will come back to you in ten years on your final point, but if the 20 year trend was flat we could at least have some confidence that the underlying cause was not ENSO related.
  37. Do the IPCC use alarmist language?
    Ned, my understanding of the usage here is that 'panel' refers to the institute as a whole, rather than a group of individuals. To expand the sentence with the current verb usage, it reads "Do the members of the IPCC use alarmist language?" Some of them may at times, but the what they produce as a collective (ie, AR4) does not. (Last post on grammar, I promise. :-)
  38. Do the IPCC use alarmist language?
    Byron Smith... Exactly. The IPCC are sounding the alarm bell but they've wrapped the clapper with rags so as to not hurt anyone's ears.
  39. New temperature reconstruction vindicates ...
    #159: "Even if 2000 decaedal averge is higher than 1990avg it does not mean the temperatures couldn have halted in the end of 90's. If they just stay on the same level they rose to, the decaedal avg will be simply higher." I assume you meant to say that 'even if the 2000 decadal avg is higher than the 1990 decadal avg, it doesn't mean temperature [increase?] [warming?] couldn't have halted in the end of the 90s.' This is still not making any sense. Consider the examples below: 
    90s   |  00s   | 20 yr avg  |  Conclusion
+.5   |  +.3   |   +.4      |  warming on halt
+.5   |  +.4   |   +.45     |  maybe on halt
+.5   |  +.5   |   +.5      |  no change
+.5   |  +.6   |   +.55     |  maybe still warming
+.5   |  +.7   |   +.6      |  still warming
    The 90s average doesn't bias the result any more than the 2000s average. But I have to admire the dedication to message: Only a true denier would say that even if temperatures are higher, it doesn't mean warming didn't halt.
  40. Carbon Dioxide - Everyone's Favorite Pollutant
    KdKd at 190 times 2. It is too bad. BP used to make insightful comments.
  41. Do the IPCC use alarmist language?
    The IPCC are not alarmist in their conclusions, and they are no more alarmist in the way they report their conclusions. Yet their conclusions are alarming and quite possibly understated.
  42. New temperature reconstruction vindicates ...
    @Ned: I stand corrected. Your response to protestant was spot on, BTW.
  43. Do the IPCC use alarmist language?
    Many scientists find the IPCC too timid in its conclusions. One of them is Andy Lacis. Human-induced warming of the climate system is established fact. “My earlier criticism had been that the IPCC AR4 report was equivocating in not stating clearly and forcefully enough that human-induced warming of the climate system is established fact, and not something to be labeled as “very likely” at the 90 percent probability level.” http://dotearth.blogs.nytimes.com/2010/02/17/lacis-at-nasa-on-role-of-co2-in-warming/
  44. Do the IPCC use alarmist language?
    A recent set of articles comment about how you can now circumnavigate the Artic in one season (without sailing in an ice breaker.) For example - http://www.physorg.com/news/2010-10-crew-circles-north-pole-summer.html . A quote from this article " Less than 10 years ago the first steel-hulled sailboat managed to get through just one of the passages, and 100 years ago, a circumnavigation would have taken six years," the "Northern Passage" crew said in a statement. " How did the IPPC reports define the probability of this being possible in 2010 ?
  45. Climate Cherry Pickers: Falling sea levels in 2010
    BP @109, You keep on digging yourself deeper into a hole. 1) Let me remind you again that this thread is about Goddard cherry-picking, and make no mistake he is cherry picking. He clearly chose those data (failing to apply the inverse barometer correction) to support his claim that "Sea level falling in 2010". 2) You say that his analysis (if one could venture to call it that) "does not make" sense. Please, don't insult our intelligence BP, you know very well the game that Goddard is playing. The fact that you are not willing to call him on it is inexcusable, and flies in the face of you assuring me a while ago that you are interested in the pursuit of truth. 3) Let me remind you that nowhere in his post did John refer to accelerating increase in SL rise over the satellite record. And you are misrepresenting what Doug said in his post @ 42. He said "TTTM, look at this graph. Notice, sea level sort of bounces along, upward". Nothing about acceleration of the rate of SL rise over the satellite record. You and Ken are arguing a strawman. 4) Now that you have introduced the strawman about rate of SL rise not "accelerating", you give a wonderful piece of curve fitting at #49. First, 2010 is not over yet (in fact the UofC data only go back to June or so), so I am not sure what you mean when you claim that the rate of increase in global SL in 2010 is 1.9 mm/hr. Additionally, you do not support any statistics to support choosing the quadratic model versus a linear model. I have processed the UofC data in MINITAB-- for the linear model over the satellite record the R-sqd =0.934 (p-value <0.001; S=4.02); for the quadratic model the R-sqd is 0.938 (p-value <0.001; S= 3.84). I also plotted the residuals, there is not much at all to choose between the two models used to fit the data. Therefore, I can see no statistical justification of why one would feel compelled to choose a quadratic model versus a linear model. Moreover, there is no reason to expect that the quadratic model will be valid beyond the training period, but I am willing to bet that the linear model does have some skill beyond 2010. How about we revisit in 2015? That all said, I agree that over the duration of the satellite record there is no evidence of an acceleration in global SL. 5) The CSIRO data up until August 2010 just came in, they show that the mean rate of increase in global SL over the satellite record is 3.2 mm/yr. Now let us place this in context. Historic data show that the rate of increase in global SL early in the 20th century was about 1.7 mm/hr (Church et al. 2008), with "with an increase in the rate of rise over this period". Church et al. (2008) note that Jevrejeva et al.(2006)used a different technique but obtained a similar global curve. Also, look at Fig. 6 in Jevrejeva et al. (2006) and Fig. 3b in Church et al. (2008)-- the rate of increase in SL has been increasing, although it seems with a distinct cyclical component. And I think it is obvious that a linear model would not fit the data presented in Fig. 3a in Church et al. (2008), and indeed they fit the data with a quadratic model. In fact, look at Fig. 1 in Jevrejeva et al. (2008) which shows the global SL from 1700 until 2000-- another quadratic model. So the data and publications show that John Cook is completely justified in saying that "So a broader view of the historical record reveals that sea level is not just rising. The rate of sea level rise has been increasing since the late 19th century" As for you choosing this statement "Sea-level rise is accelerating faster than the IPCC predicted". That is not even worth addressig becasue a) It is true (see The Copenhagen Diagnosis) and b) It is another strawman argumenat by you. Regarding point a), from the Copenhagen Diagnosis: "Sea level has risen faster than expected (Rahmstorf et al. 2007), see Figure 16. The average rate of rise for 1993-2008 as measured from satellite is 3.4 millimeters per year (Cazenave et al. 2008), while the IPCC Third Assessment Report (TAR) projected a best estimate of 1.9 millimeters per year for the same period. Actual rise has thus been 80% faster than projected by models." You also claim that "They are usually connected to alarming projections of even more acceleration in the future (yes, projections, whatever that's supposed to mean, never predictions), based on the alleged accelerating ice loss over Greenland" Are you serious or engaging in some odd form humour here? The contribution from dynamic ice loss is one of the unknowns that does not work in our favour. What about the loss from terrestrial glaciers, the WAIS and possibly even the EAIS? And what information do you have to support your insinuation that the ice loss from Greenland is not accelerating or to refute the findings of Jiang et al. (2010)? Also, feel free to argue with the findings presented by mspelto which indicate ice loss from the Greenland ice sheet has increased from about 60 km^3/yr in 1993/1999 to 80 km^3/yr in 1997-2003, to >100 km^3 in 2003-2007. Re GRACE, it is not cherry picking when it is the only data you have-- and the GRACE data have been placed in context. Are you going to accuse people of using the JASON data record or the RSS MSU data record of cherry-picking next? Thanks BP for making me waste my morning chasing down your misinformation and straw mean arguments.
  46. Explaining Arctic sea ice loss
    RSVP, I think your semantic climate sensitivity is too high. Perhaps you'd feel better if I added a calming word such as "substantially" in order to make more obvious the qualifier "...although natural factors have always influenced the state of Arctic sea ice..." How about this: In sum, although natural factors have always influenced the state of Arctic sea ice, research strongly suggests that today's decline is substantially driven by the novel influence of anthropogenic C02 we've added to the atmosphere and thus is unique in Earth's history. Come to think of it, that actually reflects research findings better, though it hardens the language in favor of anthropogenic factors. How about "significantly?" Oops, same deal. Word-smithing won't really change the fundamental meaning of the sentence, unless we're so highly tuned that we consider "is driven by" to imply "excludes all other possible factors."
  47. Explaining Arctic sea ice loss
    Chris G #36 "I don't believe you'll find any claim that the variability of sea ice is only due to CO2." Please scroll upward and read the last paragraph of the original article. As for your comment about ice in a glass: since I am on the blue pill, the drink does seem cooler to me. ...and as for the rest... "When ice melts or water evaporates, energy must be taken from the environment in order for the ice or liquid to move to a less ordered state" http://www.theweatherprediction.com/habyhints/19/
  48. It's Urban Heat Island effect
    If you thought our cities are getting warmer, you're right. "Bureau of Meteorology researchers have found that daytime temperatures in our cities are warming more rapidly than those of the surrounding countryside and that this is due to the cities themselves."
  49. Do the IPCC use alarmist language?
    It's important to point out that the IPCC is tasked with the job of assessing the risks and likelihoods. So, really Roger A. Wehage's complaints that it's too complex to assess a rather moot point. The issue at hand (the point of the main blog post) is whether the IPCC use alarmist language. I have to agree that they do the best job they can to address all sides of the issue in a way that... well, ultimately is not going to please anyone. In my mind that probably means they're doing a good job (i.e, the best job possible given the circumstances). If you think about it, the IPCC's assessment of climate sensitivity is probably the very best overall indicator for the entire issue of climate change. 1) Climate sensitivity of 2C to 4.5C with 3C as best fit. 2) Sensitivity below 2C is very unlikely. 3) Sensitivity higher than 4.5C is also unlikely but can not yet be ruled out. (Hope I have that right.) Is this alarmist? Some alarm bells should be going off in everyone's head for sure. But they mitigate that alarm by saying we have a pretty strong inclination of about where things stand.
  50. New temperature reconstruction vindicates ...
    archiesteel writes: Uh, no, you don't. See Tamino's convincing argument to the contrary. I don't think Tamino gets that right, personally. He apparently just uses the numbers in Loehle's reconstruction as they are. But Loehle's reconstruction is just centered on its own long-term mean. In order to compare Loehle to anything else, you need to recenter it using some base period. In Fig 2, the "base period" is the entire period of overlap among all the reconstructions. In Fig. 3, it's the period of overlap with the instrumental record. Both of these are defensible, though I think the latter is better. Tamino's figure (comparing two reconstructions that have different base periods without recentering them) is simply wrong, IMHO.

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