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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 125001 to 125050:

  1. michaelkourlas at 09:45 AM on 25 January 2010
    We're coming out of the Little Ice Age
    No, I'm not just looking at the CRU measurements. Take a look at NASA's Goddard Institute for Space Studies measuements (http://data.giss.nasa.gov/gistemp/graphs/). They also show global warming slowing down and almost stopping at about 2000. At the very least, if global warming has not stopped, it has definitely slowed down quite a bit, against what the IPCC has predicted.
  2. Peer reviewed impacts of global warming
    Absolute rubbish, Berenyi. Peer review-of one form or another-has actually existed for well over 150 years. The only thing which changed is that it went from being an ad-hoc process to being much more organized. It is also nonsense to try & suggest that Peer-review has slowed down the rate of scientific progress. In many fields, progress has gone ahead at an even faster pace (molecular biology & information technology stand out). If anything has stymied the rate of technological progress its the industrial sector, not the scientific community. Many very powerful, vested interests have used a host of measures to try & impede social & technological innovations that threaten said interests-whether via "Think Tanks", political lobbying or the buying & suppression of patents. Though Peer Review is imperfect, it's better than having no oversight of research, & at least the proponents of AGW can cite a wide body of peer-reviewed literature, whilst the denialists are largely forced to rely on information from web-sites like JunkScience.com & Wattsupwiththat or-worse still-joke journals like Energy & Environment.
  3. Peer reviewed impacts of global warming
    re #10 Peer review is a pretty good system Peter. It's a basic quality control for published science, and has the positive effect of ensuring that competent scientists present their work to a good standard (if they wish to publish anywhere of note). Of course it has its flaws (what example of organized human affairs doesn't?). But it's a strong part of the process of dissemination and accumulation of scientific knowledge. And of course it doesn't work in a vacuum. Most published science has already gone over the hurdles of peer review through departmental, conference or funding-source presentations, and once published has to live or die according to subsequent analysis. I wouldn't have said climate science, as science, has any particular problems. Of course it's a science that happens at this particular time to have strong political significance, and therefore it's subject to rather incessant attempts at misrepresentation and dirty tricks. But the best means of dealing with that is to focus on the science (i.e. what's passed the hurdles required to publish in a decent journal). Not sure the IPCC has any particular problems either. It's generally considered to be doing a good job of periodic assessment of the science with a view to informing policymakers and public. Of course it's not perfect either, and (like climate science and scientists in general) is subject to the rather hysterical attempts to make mountains out of molehills. Again the best means of addressing that is to focus on doing a good job. One might counter your assertions with the warning about the perfect being the enemy of the good. But in reality, those that are engaged in hyperbole and over-reaction against real or perceived errors aren't really interested in improving the systems of science...I suspect what they would like is to create the impression that the systems are sufficiently flawed that any old rubbish posted on the internet would have equivalent authority as the science. What a world that would be, eh Peter!? Otherwise, it's not easy to see what the problems are. It's good that errors or instances of poor practice are identified, wouldn't you say? That happens all the time in science (peer-review being part of that process). Identifying errors is the best means of correcting them. Not sure why we have to accompany the identification of errors with bouts of contrived indignation!
  4. Does Urban Heat Island effect add to the global warming trend?
    >"It's well established that urban areas are warmer than surrounding rural areas. >However, does Urban Heat Island (UHI) contribute to the global warming trend? >Short answer, no. Two thirds of global temperature data comes from ocean records, >free of UHI effect" Let's start with "Two thirds of global temperature data comes from ocean records ..." Looking at http://www.ncdc.noaa.gov/oa/climate/ghcn-daily/index.php?name=coverage It looks like ocean stations comprise the minority of the data. Even if one refers to Hansen, J. and Lebedev, S. 1987. "Global Trendsof MeasuredSurfaceAir Temperature" http://pubs.giss.nasa.gov/docs/1987/1987_Hansen_Lebedeff.pdf and includes shipboard data, it is still hard to account for "two thirds of global temperature data" coming from ocean records. An actual reference list for all that ocean data would really be helpful. I would find it far more credible if the source assertion for ocean temperatures was based on satellite observations rather than surface observations ... Once the actual data source counts can be sorted out, one must then validate that those sources are indeed "free of UHI effect." Specifically, one would need to look a stations in island cities, military bases, and onboard specific platforms. Density considerations are necessary when analyzing instrumentation details on sea going platforms and in coastal installations. I have collected environmental data both on land and at sea, including temperature altitude profile data and bathymetric profile data. When it comes to accounting for UHI, I'd be especially careful to account for it when it's "coming from ocean records." I remain fully skeptical and unconvinced regarding the assertion: "Two thirds of global temperature data comes from ocean records, free of UHI effect. " It would be really useful to overlay geospatial population density, transportation density, and power generation/consumption with respect to the temperature stations under consideration. Shipboard data needs to be corrected for navigational parameters, instrumentation, location and platform type. Finally, going to the Jones et al reference abstract linked in the first paragraph of the blog, one finds "Urban-related warming over China is shown to be about 0.1°C decade−1 over the period 1951–2004, with true climatic warming accounting for 0.81°C over this period." http://www.agu.org/pubs/crossref/2008/2008JD009916.shtml The period spans more than five decades (1951-2004) ... so the UHI effect is 0.5°C. One then examines Jones et al abstract again "Global surface temperature trends, based on land and marine data, show warming of about 0.8°C over the last 100 years." It's not clear from the abstract if Jones et are saying that the total change in their study is (0.81 + 0.5 = 1.3) or (0.81 total). If the first case holds, UHI accounts for 38% of the increase. If it's the latter case, then UHI accounts for 62% of the increase. The question and answer posed by the blog "does Urban Heat Island (UHI) contribute to the global warming trend? Short answer, no" is inconsistent with either case: does it contribute? Yes, either 38% or 62% depending on the case and presuming that the total climatic increase is for the same five decades and not 100 years. If it is for the entire 100 years, then it may well account for the entire change.
  5. Peer reviewed impacts of global warming
    Berényi Péter, I'm shocked. The link you quote provide a whopping 16 non peer reviwed citations, over some 10,000 in the WG2 report. And i found even more, from WMO, World Bank, and the like. Is this supposed to be the proof of non-scientific political bias?
  6. On the reliability of the U.S. Surface Temperature Record
    "Others here have parried my question rather than answered it. Is the actual data duff or not? If the data going into all the trendy models is bad then we, the public, will simply dismiss the model." Sigh. Temperature data doesn't go into the models. Neither the trendy nor the old boring ones. Temperature data is a model *outcome*, not *input*.
  7. Skeptical Science now an iPhone app
    timbo at 09:02 AM on 15 January, 2010 "I'm waiting for an Andrew Bolt (check him out SS, he's a nutbag, writes for the Herald Sun) article claiming that coz it's snowing in Jan, GW/AGW is a sham" Timbo, Andrew Bolt has used the recent extreme cold snap in the Northern Hemisphere to question predictions that winter snow would become a thing of the past. I have mentioned claims from AGW scientist Dr David Viner's who commented on this. Now I read in today's 'The Australian' that the IPCC is under fire again for making claims linking extreme weather to AGW..... "The world has suffered rapidly rising costs due to extreme weather-related events since the 1970's"- IPCC 4th assessment 2007 THEN.. "we find INSUFFICIENT evidence to claim statistical relationship between global temperature & catastrophic loses"- Muir Woods paper after peer review in 2008 THEN... "We are reassessing the evidence & will publish a report on natural disasters & extreme weather with the latest findings"- IPCC vice chairman Jean-Pascal Van Ypersele- LAST WEEK The worst of all this, was that this was all conveniently ignored before the Copenhagen summit!, why weren't we told this beforehand???
  8. On the reliability of the U.S. Surface Temperature Record
    "UPDATE 24/1/2010: There has been no direct response from Anthony Watts re Menne 2010. However, there was one post yesterday featuring a photo of a weather station positioned near an air-conditioner along with the data series from that particular station showing a jump in temperature. The conclusion: "Who says pictures don’t matter?" Not surprising. It's transparent to every scientist how ridiculous his sort of rhetoric is, but not always to his target audience. A picture or two like this is psychologically more convincing to many non-experts than any detailed objective analysis. #45, It might be a good idea to do a post on what an anomaly is, why it's used instead of raw temperature values, and what a baseline is. It's pretty basic stuff, I know, but I've seen Anthony Watts post anomaly values side by side (gistemp, HadCrut, RSS, UAH), then imply that because gistemp is larger, it's biased high. #36, Schwartz et al. mostly explains what climate scientists already understand. In the absence of manmade aerosol cooling, and the ocean time lag, more warming would be expected from industrial GHG emissions than has been observed. Schwartz explains that much of the uncertainty from deriving the climate sensitivity estimate from the instrumental temperature record comes from the uncertainty in determining the amount of negative aerosol forcing. Where he might have some contention, I think, is in his assertion that the ocean time lag in heating explains 25% of the discrepancy between observed and expected warming. My understanding is that most scientists determine that this value is a bit higher. Lastly, the instrumental temperature record is only one method for determining climate sensitivity. Other methods yield a similar best estimate as the IPCC. http://www.skepticalscience.com/Working-out-climate-sensitivity.html
  9. Skeptical Science now an iPhone app
    To David Horton (12/01/2010) It's interesting how you say that some weather patterns are a gift to 'deniers' when it suits their argument, but that well and truly works both ways. If we look at the big freeze occuring in many parts of the Northern hemisphere lets take this in the context made by AGW scientists who have been warning people that winters and snow will be a thing of the past! Below is an article from March 2000. In this article, Dr David Viner says " in a few years winter snowfall will become a very rare and exciting event" , how wrong he was! http://www.independent.co.uk/environment/snowfalls-are-now-just-a-thing-of-the-past-724017.html Is seems perfedtly okay for AGW scientists and activists to make wild and unsubstantiated claims about future weather patterns & events, but when a 'denier' merely comments & rasies questions on extreme weather, esp when that weather is cold then it's 'here they go again'. During early November, South Eastern Australia (S.A, Victoria) experienced 1-2 weeks of some very warm weather. It came as no suprise that our PM, Kevin Rudd used this as proof that we need an ETS! So once again it's perfectly ok and appropriate for AGW to use isolated weather events to push their cause, but completely unacceptable from the other side of the camp! As an aside, in Victoria, the weather 'redeemed' itself and we ended up having a very welcome wet 2nd half of the month and double the monthly average rainfall. Anyway here is more comment about the November hot spell from AGW believers.. http://indymedia.org.au/2009/11/10/its-getting-hot-in-here-november-heatwave-classic-climate-change-weather Its quite obvious both sides of the argument are guilty of using isolated weather patterns to push their cause.....
  10. Greenland is gaining ice
    The Michiel van den Broeke, et al. paper "Partitioning Recent Greenland Mass Loss" states: "Our results show that both mass balance components, SMB and D (eq. S1), contributed equally to the post-1996 cumulative GrIS mass loss (Fig. 2A)." But then, Fig.3 shows: Ice Discharge: -94 Gt/yr Surface Mass Balance: -144 Gt/yr Isn't this a contradiction? Then comes this statement: "A quadratic decrease (r^2 = 0.97) explains the2000–2008 cumulative mass anomaly better thana linear fit (r^2 = 0.90). Equation S1 implies thatwhen SMB-D is negative but constant in time, ice sheet mass will decrease linearly in time. If, however, SMB-D decreases linearly in time, ashas been approximately the case since 2000 (fig.S3), ice sheet mass is indeed expected to decrease quadratically in time" What is this "r^2 = 0.97" and how it is related to the equations: MB = ∂M/∂t = SMB – D (S1) δM = ∫dt (SMB-D) = t (SMB0–D0) + ∫dt (δSMB–δD) (S4) Any idea?
  11. On the reliability of the U.S. Surface Temperature Record
    Proposition 2: Scientists are incompetent and mistaken. We are talking about tens of thousands of scientists, from dozens of countries all over the world, in hundreds of different scientific academic, research and government institutions, from dozens of different scientific disciplines, approaching the problem from different directions, with different instruments and methods, coming to a common conclusion. While you can question the competence of some, you'd have to doubt the very fundamentals of science education worldwide to think they are all incompetent. I reject the idea that they do not know what they are talking about. jpark, I have looked at WUWT. I found very little serious comment there. I wanted to see what they made of David Barber's first hand observations of ice conditions in the Beaufort Sea last year. I looked at it at the same time that I looked at Barber's own summary report of his observations. The analysis in WUWT was one-sided, and the comments rarely rose above attacks on Barber's honesty, professionalism and competence. As I have said already, I have deeply considered the issues of honesty and competence, and have satisfied myself on those scores. WUWT is not very interesting to me as a source of valuable comment.
  12. On the reliability of the U.S. Surface Temperature Record
    jpark, no one has parried your questions, they have answered very clearly; scientists understand the nature of the data they have, and know how to interpret it. Therefore, it is not 'duff.' Just because you and I do not see how it is used simply does not invalidate it. In order to doubt the scientists' word, you'd have to believe one of two things; they are lying, or they are incompetent and are mistaken. I do not offer the other possibility, that they are competent and mistaken, because while that is possible in the individual case and happens all the time, it is extremely unlikely when we are talking about tens of thousands of scientists in aggregate. This is a question you and I can examine without understanding the science. Proposition 1: Scientists are lying. I looked for a motive here. Two have been offered, that they are greedy, and that they are politically motivated. I dismissed greed because there are too many ways for scientists to make a good living in our world. A few may compromise their ethics to keep jobs or earn a few more dollars, but not the majority of scientists. Please grant that science is a difficult field and requires greater than average intelligence, thus some degree of foresight. Any scientist tempted by the short term gain that might accompany colluding in a lie, must realize that the discovery of that lie would mean the end of a hard-earned career. Examine the other essential component of the greed theory. It leads to the question of political motivation. Who would pay so many scientists to lie, and why? I am told they are global elites who want to destroy the Western economy. It seems counter to common sense that people would wish to destroy the system that gave them power. I had to either reject the theory that scientists are lying, or confidence in my own reasoning power. Sorry, jpark, I rejected the idea that tens of thousands of scientists gave up the very principles that led them to the difficult career field of their choice, to lie for a few dollars they could easily earn elsewhere. To believe that there is a vast political conspiracy, and that scientists from all over the world have bought into it, I think that a tin foil hat would not suffice. I would need a tin covered home and car, and a full-body tinfoil suit to wear every time I leave my tin house. Political motivation, rejected. I conclude that the majority of scientists are not lying.
  13. Peer reviewed impacts of global warming
    Berényi Péter at 06:36 AM on 25 January, 2010 Your polymath attention to matters such as hypothetical issues w/peer review makes those times when you appear here with an attempt at scientific arguments against mainstream science automatically appear less credible. Better stick to science, or your reputation will wear out prematurely.
  14. On the reliability of the U.S. Surface Temperature Record
    lord_sidcup at 01:03 AM on 25 January, 2010 I noticed the same thing. jpark sailed in under false colors, look like. I seem to remember something to the effect of "fence sitter", but unfortunately that seems to have been another performance of an old, tired gambit. Waste of time. So many people on the network, so few basic narratives to choose from, boredom is the upshot.
  15. Berényi Péter at 06:36 AM on 25 January 2010
    Peer reviewed impacts of global warming
    John, anonymous peer review is not a sacred cow. In it's present form it was introduced only after WWII, when the US as the sole indisputable victor of the armed conflict took over leadership in science. Government spendings soared and the state felt the need of some handle on this crowd of weirdos called scientists. The procedure has it roots in eighteenth century state censorship by absolute monarchies. The political charge of the institution as it is practiced now is related to its introduction and dissemination by US government policy guidelines. By the time of its post WWII reinvention, early forms a peer review were mostly abolished and replaced by a more informal and free system. As a quality control measure, it neither performs particularly well nor does it promote efficiency. After WWII scientific progress definitely slowed down compared to the pace of previous (from mid XIX. to mid XX.) century. Especially if the prodigious increase in both the number of "scientists" and expenditures are taken into account. The sorest spot is anonymity with its lack of accountability. Open peer review can be a remedy, perhaps. Nature (2006) | doi:10.1038/nature05005 Can 'open peer review' work for biologists? Biology Direct is hopeful. Eugene Koonin, David Lipman, Ros Dignon &. Laura Landweber http://www.nature.com/nature/peerreview/debate/nature05005.html So, peer review in itself would solve neither the problems of climate science in general nor those of IPCC in particular. The reason IPCC should have sticked to peer reviewed literature is entirely different. They have it in their own guidelines as a requirement. Yet in their AR4 report they frequently rely on non peer reviewed NGO material from WWF, Greenpeace and the like. It was the same with this Himalayan glacier issue, but the example is far from unique. More Dodgy Citations in the Nobel-Winning IPCC Report blogpost by Donna Laframboise http://nofrakkingconsensus.blogspot.com/2010/01/more-dodgy-citations-in-nobel-winning.html The whole scandal is more like a public political and legal issue than an internal affair of science.
  16. Peer reviewed impacts of global warming
    RE #8 Ned, "six degrees",that's great, but to quote an old adage, "if a tree falls in the forest, and there's nobody there to hear it, does it make a sound??? The short answer would be no.
  17. Peer reviewed impacts of global warming
    I'd like to second birdbrainscan's recommendation of "Six Degrees" (though note that it's by Mark Lynas, not Fred Pearce). It does a fantastic job of summarizing the peer-reviewed literature on impacts of warming, grouped by magnitude of warming (1, 2, 3 ... 6 degrees). Very eye-opening.
  18. Peer reviewed impacts of global warming
    Just this morning there was a letter to the editor about this. It's amazing how fast the denier camp to jump on these things. And naturally they're using this as an argument against global warming.
  19. Peer reviewed impacts of global warming
    How about the negative geopolitical factors such as: 1) China and India pass the US as economic superpowers 2) Increased immigration 3) Higher food costs 4) Greater government subsidies (higher taxes) 5) Higher insurance rates 6) Increased authoritarian governments 7) Increased terrorism 8) Nuclear proliferation 9) Regional and global wars between countries with nuclear weapons which I outline here and also on my blog at: http://profmandia.wordpress.com/
  20. Peer reviewed impacts of global warming
    Excellent stuff, John. I do agree with Ned, though, on the wording of that one sentence.
  21. Skeptical Science now an iPhone app
    I get your point but we are trying to cut back to individual components. Its not me that is suggesting 1Wm-1 change in radiative forcing will lead to 0.6oC change in temeparture at the surface its climate scientists. It is this I have a problem with, maybe you are agreeing things have been over simplified.
  22. Peer reviewed impacts of global warming
    we, as fleas on the butt of gaia can, do nothing to affect a changing climate. therefore the solution is to adapt not try to impede.
  23. Peer reviewed impacts of global warming
    Didn't the original report state that the Himalayan glaciers would be substantially reduced by 2035? Quite a bit different than disappearing by 2035. If the IPCC is this succeptible to media hype, then the deniers have already won, and all the good work here is for naught. Might as well grab some popcorn, sit back, and watch the world burn. Unless you all find your balls, and fight back. I won't hold my breath.
  24. Peer reviewed impacts of global warming
    Good work on this page. Have you read Fred Pearce's book _Six Degrees_? He references hundreds of peer-reviewed citations in constructing his account of expected impacts of each added degree (I read up through 3 degrees before I wimped out on the rest!) Maybe you'll want another source or two on glacier loss impacts, knowing how this is the current hot button? Can you re-word this one for clarity? "Increased deaths to heatwaves - 5.74% increase to heatwaves compared to 1.59% to cold snaps" First the dash confused me as I read it as a minus sign; second, is the 1.59% to cold snaps a (smaller) reduction? (and is that apples to apples, or are these % changes in two distinct absolute numbers which might be unequal? The 2003 heat wave in Europe killed ov 37,000, while the first list I found (wikipedia on disasters by death toll) lists far fewer deaths from "blizzards" (in the hundreds annually), and recent news headlines mention, e.g. 22 dead in the UK from the past month's extreme winter weather.
  25. Peer reviewed impacts of global warming
    "If the IPCC's mistaken prediction of disappearing Himalayan glaciers taught us anything [...]" John, most of us understand what you mean by that, but it might be worth rephrasing slightly. Obviously, the majority of glaciers in the Himalayas are in fact disappearing; the "mistake" was suggesting that could happen by 2035. But someone who comes here from a site like WUWT might take your opening sentence as confirmation that glaciers are not in fact disappearing at all.
    Response: Agreed, I can see how the original wording could be miscontrued - have updated the text.
  26. michaelkourlas at 02:42 AM on 25 January 2010
    Tree-rings diverge from temperature after 1960
    Mr Cook: Regarding: "The divergence problem is unprecedented, unique to the last few decades, indicating its cause is anthropogenic." One thing I don't understand is this assumption that if we don't know what causes something in the climate system to happen, it must be us. I think the best way to explain this is the study on the links between telephone poles and cancer, where scientists found that in areas with high per-capita telephone poles, there were higher rates of cancer. Thus, telephone poles must be causing cancer! Now, this sounds silly, because there are other factors which may cause an increase in both factors (something to do with industrialization/urbanization, etc.), but it is quite comparable to current climate science. We assume that because we can't find any other natural factor that could cause the current warming (or tree ring divergence), it is automatically us. But we can't assume that. We have to assume it is natural until it is proven to be caused by us.
    Response: It's not definitely proven that the divergence problem is caused by us but the fact that over the last 1000+ years, it's only occured in the last 40 years is highly suggestive, particularly when likely causes like global dimming are anthropogenic. However, the key point is not that divergence is anthropogenic but that the evidence indicates divergence has not occured before recent decades so tree ring proxies are reliable before 1960.
  27. michaelkourlas at 02:31 AM on 25 January 2010
    Svensmark and Friis-Christensen rebut Lockwood's solar paper
    Mr Cook: Why did you not address the other graphs that were presented in the report (i.e. the sea surface temperature graph and the first tropospheric temperature graph)? Those seemed to have a fairly conclusive correlation as well. In addition, as a side note, the second set of tropospheric graphs was not necessarily created by Svensmark and Friis-Christensen. They are also present in the ISAC (http://www.spacecenter.dk/research/sun-climate/Projects/isac) final report (http://www.spacecenter.dk/research/sun-climate/Projects/resolveuid/6151e93eeb020789ed45ca109ab52346), and that paper does not cite Svensmark and Friis-Christensen's reply to Lockwood and Frohlich.
  28. michaelkourlas at 02:25 AM on 25 January 2010
    We're coming out of the Little Ice Age
    Mr. Cook: I think the whole flaw in the climate change argument can be expressed examining the words you have just used when saying "What the science really says": "The main driver of the warming from the Little Ice Age to 1940 was the warming sun with a small contribution from volcanic activity. However, solar activity leveled off after 1940 and the net influence from sun and volcano since 1940 has been slight cooling." OK, fine. While I don't necessarily agree with the sun portion (see Reply to Lockwood and Fröhlich - The persistent role of the Sun in climate forcing here - http://www.spacecenter.dk/publications/scientific-report-series/Scient_No._3.pdf/view), let's say everything you have said there is true. Even so, that does NOT automatically mean: "Greenhouse gases have been the main contributor of warming since 1970." Do we have any direct proof of that? Do we know exactly how much radiative forcing the greenhouse gases we emit produce? And do we know how much they produce when within the extremely complex climate system, as opposed to within laboratory conditions? Or is it just an assumption, considering we have exhausted all the possible natural causes that we can think of? I think that there may be other natural causes (maybe even ones we have not yet discovered) causing this kind of warming, at least to a certain extent. Syun-Ichi Akasofu here (http://people.iarc.uaf.edu/~sakasofu/little_ice_age.php) wrote about the possibility that much of the current warming could be simplified down to a natural 0.5 degrees C linear trend, with superimposed fluctuations and oscillations. Most importantly, he also notices that global warming has essentially stopped since 2000. This lack of warming does not agree with IPCC predictions. Instead it gives more credibility to this theory, as it could be explained as the most recent oscillation winding down and continuing on the 0.5 degrees C linear trend.
    Response: The direct proof of the radiative forcing from rising CO2 is explored in the empirical evidence for an enhanced greenhouse effect.

    Re Akasofu's assertion that "global warming has essentially stopped since 2000", presumably, this is based on the HadCRUT surface temperature record which omits areas of the globe of extreme warming in recent years. A more comprehensive analysis of the Earth's energy imbalance finds the planet continued to accumulate heat past 2000 right up to the end of 2008 (where the analysis ends). Global warming has not stopped.
  29. Berényi Péter at 02:14 AM on 25 January 2010
    Skeptical Science now an iPhone app
    Let's put it another way. Some excess heat in last December might have gone to the Arctic, leaving North America, Europe and Siberia in the cold. It could not come from anywhere else, for the Arctic, north of the 80th latitude is in permanent shade form about 22 October to February 20. Does it mean that "global warming" just shifted to the North and stayed there? No. Remember, the map at the top of this page is about temperature anomalies, not temperatures themselves. If parts of the Arctic are up to 8 centigrades warmer than average in December, they are still damn cold, below -20°C (-4°F). And now this excess heat has gone somewhere else again, circumpolar temperatures dropped by some 15 centigrades in just two weeks. The question is: Where did global warming go this time? One thing we do know for sure: heat does not go from a colder place to a warmer one, at least not as long as LTE (Local Thermodynamic Equilibrium) holds. As it always does in the atmosphere below perhaps 50 km (30 miles). So. The question is transformed to another one: Is there a place around the North Pole which is cold enough to suck away the excess heat from there during dark winter night? The answer is yes. There is one and only one such place. The temperature of the high skies is 2.7K (-270°C, -454°F). Except the solar disk of course (with an effective temperature of 5780K), but it occupies less than one hundred thousandth of the entire sky and is not visible from the Arctic this time of the year anyway. The only other conceivable heat sink around is seawater. But open seas north of Scandinavia, even if close to freezing, are much warmer than deep space and also considerably warmer than less cold than usual arctic air. They could do some heating job, cooling not, for sure. So, on this particular occasion global warming ended up in space, since it had nowhere else to go. Carbon dioxide was not able to prevent it, somehow. Some lax scaremongering about heating up the Universe by the Arctic perhaps? AUW (Anthropogenic Universal Warming) sounds cool, doesn't it? Anyone?
  30. On the reliability of the U.S. Surface Temperature Record
    Interesting. jpark arrives, writes more or less the same thing 3 times, then goes wildly off-topic. He tells us he will carefully read the links people have provided for him, but somehow I doubt he will. I visit this site to learn, not to have my time wasted. Thanks for the interesting and informative comments that others have made.
  31. On the reliability of the U.S. Surface Temperature Record
    There is no UHI or microclimate influence over the oceans which cover 70% of the earth's surface. Trends in temps from these areas are comparable to those over land. Case closed.
  32. The chaos of confusing the concepts
    stevecarsonr, although i'm not Jacob Bock Axelsen (and not even expert on chaos), let me comment on a couple of points you made. First, it's not true that "Any system with positive feedbacks is likely to be unstable". It's just a possibility, they _might_ be unstable. It's definitely true if they have only positive feedbacks, but the climate system has at least on strong negative feedback, thermal radiation. Indeed, earth climate proved to be quite resilient to warming much stronger than projected for the near future. The example of slowing or shutting down THC is misleading in what you consider regional changes in temperature but using global heat fluxes. The correct heat balance for the northern hemisphere alone would include also ocean and atmospheric circulation, i.e. all the sources of heat fluxes. So, that an initial warming may lead to cooling should not come as a surprise, nor should the resuming of warming afterward. Indeed, the seesaw behaviour is hardly considered chaotic.
  33. The chaos of confusing the concepts
    Chris: Re your comments from 10:31 AM on 24 January You said: "I (and everyone here, I think) was using it as an example 'though. It's not really chaotic behaviour (it has its chaotic elements on a microscale), but it's really a stochastic phenomenon that is essentially predictable, if not in relation to the precise timing of events, at least as a phenomenon that is a definite and predictable consequent of particular conditions. "So, for example, it would likely be possible to model N. hemisphere ice sheet dynamics and ocean circulation during the last glacial period to reproduce the Daansgard-Oeschger (D-O) events, within an understanding of the conditions under which these events occurred (not sure if this is yet understood very well). " How do you know this is "essentially predictable"? The thermohaline currents are complex with difficult boundary conditions - the shape of the oceans along with the starting point of exactly the salinity, temperature and momentum vectors on your modeling day zero. Then you have the complexity of the interaction with the atmosphere, where dependant upon those conditions you might have more or less heat transferred, more or less momentum transferred, and depending on the cloudiness, more or less solar radiation received. And then you have the equations governing the melt rate of the Greenland ice. A nice analogy - the wall being knocked down - perhaps relevant, perhaps not. Analogies can be useful illustrations, but first of all, is it a correct analogy? I'm actually amazed that you are so confident that the THC shutdown can be modeled accurately. The dual pendulum is much simpler. But it's chaotic. THC might be non-chaotic and just very complex. But surely the starting point in determining chaotic or not is actually to know what equations we are dealing with?
  34. Miriam O'Brien (Sou) at 22:59 PM on 24 January 2010
    On the reliability of the U.S. Surface Temperature Record
    Marcus, there is a police investigation being conducted into the theft of the emails. http://news.bbc.co.uk/2/hi/uk_news/england/norfolk/8453117.stm
  35. The chaos of confusing the concepts
    Jacob Bock Axelsen: Re your follow up comment (06:01 AM on 24 January). I think I get the first point. In a well-understood system there are (or maybe) areas of non-chaotic behavior and also areas of chaotic behavior. And this is all non-controversial, chaos 101 perhaps. Then your comment which begins: "To exhibit chaos you need to be able to delay heat transport (advection) through fluid dynamics.." I might be reading into your comment what others say, so apologies if I am putting words into your mouth.. one way of looking at the earth's climate is almost like the billiard ball model - the basic thermodynamics govern the temperature, the rest is just like the bubbles in the boiling of water - it's extremely well-defined how long it takes to boil a kettle of water - and the fact that we don't know where the bubbles are, although interesting, is irrelevant. Ie in that example, chaos probably exists at a micro level, but the key parameters of importance are well-known and simple to calculate. So in climate, the heat in due to the sun and the absorption and re-emission of long wave radiation by water vapor and GHGs has to be balanced by the OLR. And nothing can really disturb that because the fluid dynamics of the situation is extremely "non-turbulent". If I've not captured the essence of your argument time to step in. And if I did get the gist, I would say.. However, unlike turbulent fluids, the earth's climate is full of coupled positive feedbacks as well as very non-linear and non-understood negative feedbacks. The positive feedbacks include water vapor (increasing with temperature), CO2 outgassed from the ocean (increasing with temp all other things being equal), ice albedo reducing with temp (therefore increasing solar radiation received). Negative feedbacks include the T^4 increase in outgoing radiation with temp. Large unknowns that are probably negative include clouds and aerosols. Any system with positive feedbacks is likely to be unstable. Start a movement in one direction and your positive feedback re-inforces it. Now that does not prove "chaos". But it certainly does create instability. That's why the THC is an interesting one because heating up the arctic can lead to cooling down the arctic, even though we don't have "turbulent fluid flow". Let's delve into the uncertainty here for a minute - heating up the arctic might instead lead to large releases of methane gases from permafrost thus a large further warming. (Not sure where the research is on that at the moment). Heating up the arctic might reverse the THC, thus a cooling. Which one happens first? We have a system with large positive and negative feedbacks. That is just one part of the climate. So I believe that to claim as your original post did that the system is "not chaotic" needs a lot more evidence.
  36. On the reliability of the U.S. Surface Temperature Record
    Oh, & before you say that this is simply limited to ground based stations Remote Sensing Systems (one of the groups which processes data from the microwave sensing satellites) shows the following anomalies. For the 1980's, the average anomaly (when compared to the 1979-2000 average) was -0.065 degrees C. For the 1990's, the average anomaly was +0.083 (a change of +0.148 degrees) & the average anomaly for the 2000's was +0.258 degrees (or a change of +0.175 degrees). Again, an acceleration in the warming trend.
  37. On the reliability of the U.S. Surface Temperature Record
    Consider this jpark. The average global temperature anomaly (compared to the 1961-1990 average temperature)-according to GISS-for whole of the 1960's was -0.012 degrees C. For the 1970's, it was +0.002 degrees C (a change of +0.0122 degrees). For the 1980's, it was +0.18 degrees C (a change of +0.178 degrees. For the 1990's it was +0.321 degrees (a change of +0.141 degrees-would have probably been a higher change except for at least one major volcanic eruption) & for the 2000's, it was +0.515 degrees C (a change of +0.194). So we essentially see an acceleration in the rate of change for each decade, in spite of the fact that there was a downward trend in solar irradiance (of around -0.3 watts/meter squared per decade) over that same period. So I really don't see where the case for skepticism is.
  38. On the reliability of the U.S. Surface Temperature Record
    More points jpark. Inquiry or not, the denialists who hacked & distributed the CRU e-mails have now had close to 3 months to find something truly damning about the way in which CRU has collected &/or manipulated the data. That they've not presented any case of fraud in this time strongly suggests that this is because no evidence exists to prove it. I'd personally like to know when there is going to be an inquiry into who hacked CRU-& who paid them-& when those responsible will be brought to justice (last time I checked, Hacking was a MAJOR CRIME in most constituencies). That such an inquiry hasn't taken place suggests that some very powerful vested interests were behind the hack. One wonders what you want, jpark? If graphs showing the warming trend don't suit you, then what about the images of the Earth covered in ever greater shades of orange & red showing the extent of warming over the last 30 years? Graphs remain the very best way of showing how the minimum & maximum temperature anomalies for each decade have changed. As to why certain stations are omitted, it might be for any number of reasons. Maybe local conditions meant the station was off-line for too many days out of a year, or maybe some localized event caused the station to become an obvious outlier. Maybe they simply had enough replicate data points, from a specific region, to get an average with a sufficiently small margin of error. The point is that the deletion of a handful of stations across the globe isn't suddenly evidence of a conspiracy. What is evidence of a conspiracy, though, is how many of the official denialist groups & individuals have strong ties to the mining & fossil fuel industries.
  39. On the reliability of the U.S. Surface Temperature Record
    jpark, can you be a little more specific about how the Met Office "got it wrong"? If you're talking about the recent cold snap, that was caused by an unforeseen change in the Arctic Oscillation, & has absolutely nothing to do with broader warming trends. What Menne's paper shows is that, in spite of the claims by people like Watts, so-called "poorly sited" weather stations are showing only a negligible difference in both their minimum & maximum temperature readings-over time. This therefore means that poor siting of US weather stations cannot be used to explain the global warming trend of the last 30+ years. This is hardly news, as satellites have shown an almost identical warming trend over the 30 years they've been taking readings. Your claim about "managed data" is meaningless, as *all science* is dependent on the manipulated-or management-of raw data. To try & equate "management" or "manipulation" with fraud is to essentially impugn the entire scientific establishment. Also, as someone who actually *knows* people in the IT industry, I can assure you that Y2K was not a hoax (though some news agencies deliberately overstated the threat). Had nothing been done about it, many industrialized nations would have been disrupted for days-if not weeks. Last of all, many of the people who helped create the sub-prime mortgage crisis walk in the same circles as those who're pushing the denialist cause in the media. Their motives are also identical-*profit*. That's why I'm so skeptical of the denialist case.
  40. The IPCC's 2035 prediction about Himalayan glaciers
    Charlie A, i did NOT say it's correct, i did say it's just simple math. Try yourself 2840/(1966-1845)=23.4 and 2840/(1966-1945)=135.2 and you'll see where the inconsistency in that table comes from. They guy who wrote the table probably mistyped the number and came out with the wrong rate. Or you mean it was intentional? In my life i've never seen a thousand pages book with no such errors and sometimes even happen in peer reviewed papers. Anyway, being the error really irrelevant for the whole picture I find the pertinacity you show by cross-posting the same "question" really pointless.
  41. On the reliability of the U.S. Surface Temperature Record
    Albatross - guys, thanks. The trend and climate models are great. I will study them some more, and of course I find them persuasive but my immediate reaction is 'oh, more graphs with dots on, is that it?' Others here have parried my question rather than answered it. Is the actual data duff or not? If the data going into all the trendy models is bad then we, the public, will simply dismiss the model. The Met Office in the UK got their predictions (and models) badly wrong this year while, to their utter horror, a chap called Piers Corbyn got it right. So much so that the BBC are considering using a different company. I know this has to do with 'weather' rather than 'climate', but let's face it if you cant predict one then the other looks fanciful. The UK Gov are setting up a parliamentary inquiry into the CRU leaked emails - this is good because it should be thorough and open. But it does mean, Doug, that you cannot say there is nothing to the emails and everything is fine. The IPCC report is, I am afraid, also important. If it includes rather wild speculation about Himalayan glaciers then the whole report looks rather suspect. Ian says that deleted stations are showing greater increases of warming - then why the heck are they not included in the data? Why do we have this adjusted/deleted/averaged/smoothed picture of what is happening - why not real/complete/comprehensive? So back to the topic here - if Menne's paper just tells us that the surface station data does nice trends then I, for one, am still left scratching my head. The case for catastrophic global warming seems too dependent on 'managed data' to me. After the Y2K bug, the sub prime mortgage/financial crisis there is good reason to be sceptical. This is very very poor PR - there has to be better than this.
  42. The IPCC's 2035 prediction about Himalayan glaciers
    Riccardo says at #28 "i just pointed out that plugging in the correct starting time the calculation of the rate is correct. " I ask again, what is your reference for saying that 1945 is the CORRECT starting date when all of the available literature points to 1845 (or 1847) as the correct starting date associated with the 2840 meters of retreat. To put it more simply, other references, such as 1958 reports make it clear that the 2840 meters of retreat is approximately correct, that 1845 is approximately correct, and that IPCC or whoever originated the chart incorrectly calculated the time span from 1845 to 1966 as 21 years rather than 121 years. These errors make it even more relevant that nominations for AR5 reviewers, which close on March 12th 2010, are not allowed to be submitted unless you are one of a certain list of privileged organizations chosen by the IPCC. I have been unable to obtain this list. The IPCC would be well served by including some reviewers without a strong confirmation bias in favor of AGW.
  43. On the reliability of the U.S. Surface Temperature Record
    Deniers are very good at confusing lay people in the use of absolute temperature and anomalies. For example Joseph D’Aleo and E. Michael Smith have accused "NOAA researchers of strategically deleting cherry-picked, cooler-reporting weather observation stations from the temperature data". They say that by ignoring these cooler stations the global temperature is artificially raised over what it would be if the stations were included. However, if you actually look at where the deleted or ignored stations are they are in areas of the world which are experiencing much faster rates of temperature increase than average (northern Canada, northern Russia). Thus their omission is actually lowering the global average, the exact opposite of what D'Aleo and Smith are saying.
  44. The IPCC's 2035 prediction about Himalayan glaciers
    nofreewind. It may not stop snowpack from forming, but it will effect the depth & total extent of the snowpack in the future-which *will* impact on future fresh water supplies. You see, even without global warming, we're already running into problems providing water to our populations. Imagine how much worse it will get if our sources of fresh water become depleted by global warming? That's not a "scare", it is something which we should be genuinely concerned about-in spite of efforts by the fossil fuel industry to try & cast doubt on the issue.
  45. On the reliability of the U.S. Surface Temperature Record
    jpark. Trends are very important because they tell us a lot about the *rate* of change. This is especially important if we can compare it to rates of change in the past. You see, though climate has changed in the past, all the available evidence suggests that it has *never* changed as rapidly as it has in the last 30-60 years, in spite of a relative lull in Total Solar Irradiance. That is why climatologists are so concerned, in spite of the efforts of people like Watts to confuse the issue.
  46. On the reliability of the U.S. Surface Temperature Record
    I've been following these threads and seeing how everything is going back and forth. Considering when somebody turns on the news and watch the weather report, we are presented with it in absolutes. So to an average laymen I could see how it seems to make more sense to want to see the data presented like that. And considering that the pdf on WUWT is very pretty and professional looking I could see how people will believe it. (He must have an army of dedicated followers, no wonder he doesn't want to report anything different, he will lose his crown) It wasn't until I started playing around with temperature data myself (DIY-Statistics) that I could understand it a whole lot better!! Is there any room for a post John or Mark on "anomalies verses absolute" or "this is what a raw reading looks like, this is what has to be done to extract sense from it..." (with lots of pictures of course, people like their pictures)?
  47. The chaos of confusing the concepts
    I think batsvensson's distinction between linear and nonlinear forcings is a red herring here, though I could be wrong (I'm not an expert in this). We can predict that (outside the tropics) it will be warmer in summer than in winter because we have a conceptual model of a forcing (the time evolution of the solar zenith angle at a given latitude as determined by the earth's axial tilt) that is large enough to override short-term variability in the weather. There are of course all kinds of feedbacks, positive and negative, that amplify or reduce that radiative forcing. Nonetheless, we can be confident that the magnitude of that forcing is large enough to make the winter-to-summer difference semi-predictable. Likewise, we have a good conceptual model of another radiative forcing (absorption of outgoing long-wave radiation by greenhouse gases) that is also becoming large enough to have a detectable influence on climate. We can't predict the weather in 2050 (just like we can't predict the weather next July), but in both cases we know there are predictable radiative forcings that will make it warmer (on average) in summer than in winter, and in a 500 ppmv CO2 atmosphere than in a 300 ppmv CO2 atmosphere.
  48. On the reliability of the U.S. Surface Temperature Record
    jpark: You're starting to get all mixed up here. "...last year we found out that CRU scientists made a hash of doing the data." Wrong. Be careful, there are a number of people with an unhealthy obsession with old email, to the point they've actually set up a web site all about it and apparently spend their days sifting through this stuff. There's really no "there" there. "Then Copenhagen fails." And that does not have anything to do with surface stations in the US. "Then this week Pachauri gets it in the neck ..." Again, nothing to do with this topic. "What does a trend mean..." A trend tells you useful things, such as whether you can expect your coffee to ever brew. "Because if those temps/trends are slightly higher than they should be and so, in reality, only slightly higher than older temp station data, or even older historic data then, yes, we have global warming but not very much..." There you go! That's the useful part! The trend provides confirmation of theory via observation, validation of models, etc. And that's why Watts et al are so determined to distract you from the importance of trends. Easy once you go through the steps, plus remember these folks are doing the same thing you used to see in word problems: throwing a lot of chaff in the air to confuse you so you can't come to a useful conclusion. Don't let yourself flunk the test.
  49. On the reliability of the U.S. Surface Temperature Record
    jpark at 07:05 AM on 24 January, 2010 Hi Doug! Many thanks, nice explanation. - But still not good enough, and I'm sorry. "I do understand the paper but still feel it does not, like a lot of posts here, answer the quite basic Watts question of how accurate the stations are." When you use the phrase "how accurate the stations are" I think it betrays that you don't understand the paper. It does not matter at all if the stations are accurate. Their utility for telling accurate absolute temperature from day to day is entirely separate from their utility for revealing a climatic trend. All that matters for extracting a trend is whether or not there's a unidentified longitudinal change of bias in measurements resembling a trend in temperature. More, that unidentified longitudinal change must be approximately the same for a multitude of stations. As it happens, there is no unidentified longitudinal bias change that meets that requirement, but there is a -know- reason for observing a trend, namely a change in climate.
  50. On the reliability of the U.S. Surface Temperature Record
    jpark, "if those temps/trends are slightly higher than they should be and so, in reality, only slightly higher than older temp station data, or even older historic data then, yes, we have global warming but not very much" Exactly, but it ain't so. In principle it might be a resonable concern, in practice it does not stand up an in depth analisys. Remember, people working on it check the readings for possible biases/errors; something may slip through the check but, well, just some. And unless you belive in the bad intentions of the researchers, errors and biases (plural) tend to average out. Don't be confused by absolute temperature and anomaly. The former is more intuitive given that it's what we feel. The latter has the advantage of being more stable and correlated over long distance and time, then more easily shows an underlying trend, which is what we are interested in.

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