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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 67751 to 67800:

  1. Ocean Acidification Is Fatal To Fish
    Muon - atmospheric CO2 in parts per million (ppm) can also be expressed as a mole fraction - micro mol/mol. According to Dalton's Law (of partial pressure) the ratio of CO2 partial pressure to total atmospheric pressure will be the same. Therefore to convert to Pa (Pascals) - 2300 micro mol/mol x 101.325 kPa (standard atmospheric pressure) = 233 Pa. Or expressed another way: 0.0023 x 101325 = 233.
  2. Ocean Acidification Is Fatal To Fish
    Atlantic Cod stocks have taken a beating in a lot of their range. A large part of the current fishery takes place in Iceland. There is a very good pH dataset for the Iceland Sea(Olafsson 2009) the aragonite saturation horizon is at about 1700 meters and shoaling four meters a year but it is still a long way from the 600 meter depth range of Atlantic Cod. There is never good news in OA but the fact that Atlantic Cod are a very large aqua-culture fishery in Norway means the sensitivity of Cod eggs and juvenile fish to elevated pCO2 will be studied carefully. Maybe like the oyster industry in the Northeastern Pacific agua-culture will find some ability to adapt. For fishermen like me who are dependent on wild stocks the effects of O/A will much more difficult. We will be somewhat tethered to what aqua-culture can learn about our mutual problems. Bruce
  3. Roy Spencer on Climate Sensitivity - Again
    Albatross, I agree when you say "Or it is both, which is what I think is the most plausible explanation", and I agree that Christy's comment about 1998 is wrong (as are most "skeptic" comments that mention that year). The current blog post of S&C does jive with your "But Spencer and Christy do not agree that the rate of warming is increasing". By saying that the rate is decreasing, S&C are admitting that the some of the trend increase (particularly recent) in the graph was due to correction of errors in the UAH data. So the corrected error in some cases may be more than what is shown in the graph and in other cases is obviously a lot less as they explain (e.g. the jump in trend due to El Nino in 1998). But the graph does not separate out which is which. The label in the article "Corrections made to the University of Alabama-Huntsville temperature record over time." is misleading.
  4. Roy Spencer on Climate Sensitivity - Again
    Eric @33, That is not my understanding or how I interpret the graphic. My understanding is that those corrections are applied to the entire record, retroactively. Those corrections have resulted in a net increase in the rate of warming in the UAH data. Either that or the rate of warming is accelerating quite rapidly over the satellite era. Or it is both, which is what I think is the most plausible explanation. But Spencer and Christy do not agree that the rate of warming is increasing. In fact, Christy is claiming in the press release that there has been little or no warming since 1998. Now where have we heard that fallacy before? The fact remains that many of the errors in the satellite data led to a low bias, and going by other groups like STAR and UW, the UAH data (and to a lesser extent the RSS data) are still biased low. And let us not forget that Spencer and Christy were reluctant to accept that their product had a cool bias when it was pointed out to them by Trenberth and Hurrell back in 1997. The history and observations hardly supports Spencer and Christy's claim that their product is the gold standard. This is all about spin and PR for Christy and Spencer, sadly not about science. Science for them is just a means to an end.
  5. Roy Spencer on Climate Sensitivity - Again
    In the comments section at the Washington Post article (link above), John Abraham defends the graphic shown in #27 thusly: "The intent of this graph is to show that there have been continuous errors in the UAH results and as time has progressed, fixing those errors has resulted in UAH data being brought into closer and closer agreement with the rest of the scientific community." But the graphic shows neither the errors in UAH results nor a comparison with the rest of the scientific community. The points in the graph (and specifically their upward slope) are the result of two things: the temperature trend increasing over time (especially considering that UAH starts in 1979) and errors in the UAH results that were fixed. The label under the graphic in the article is still misleading, unfortunately.
  6. Ocean Acidification Is Fatal To Fish
    Tom, cold water being able to absorb more CO2 is definitely part of the answer, but so too is eutrophication - where nutrient run-off from agriculture (mainly) ramps up phytoplankton growth (they're surface-dwelling marine plants). During phytoplankton blooms, large volumes of CO2 are utilized as phytoplankton absorb CO2 into organic tissue. When they die a week or so later, they fall to the ocean floor and are broken down by bacteria, thereby releasing the CO2 they stored in their tissue (remineralization). This makes the ocean floor seawater more acidified. The 'Biological Carbon Pump' was discussed in the SkS post Ocean Acidification: Corrosive waters arrive in the Bering Sea And another culprit is increased upwelling in some regions in response to ocean circulation changes brought on by global warming. These processes acting together are rapidly acidfying the subsurface ocean in cooler regions of the globe, and are also de-oxygenating these areas. Anyway, I have future ocean acidification posts covering these topics.
  7. Ocean Acidification Is Fatal To Fish
    The linked paper under 'equivalent to atmospheric CO2 levels of 2300 ppm' in the post states: Peak pCO2 values of >230 Pa (>2300 μatm) and pH values of < 7.5 Those are pressures; I understand that 230 Pa is equivalent to 2300 x 10^-6 atmospheric pressure, but how does that produce an equivalent volumetric concentration of 2300 ppm?
  8. Plimer vs Plimer: a one man contradiction
    In describing Ian Plimner’s new book, How to Get Expelled From School: a guide to climate change for pupils, pundits and parents, John Howard referred to leftie science teachers as being the problem regarding proper debate in relation to climate change. The book is supported by the Institute for Public Affairs, and the comments were made at the book’s launch at a meeting of mining company executives. Ian Plimner, and his fellow IPA scientist mate Bob Carter, have attacked the scientific consensus related to climate change; that global warming is occurring and is causing climate change and is due to excess human emissions of greenhouse gases like carbon dioxide. In trying to debunk this hypothesis, they have also attacked the integrity of world’s climate scientists. They have attacked the integrity of the national science academies of the world’s leading nations. They have attacked the stance made by many of the world’s leading companies. They have attacked the integrity of the scientific process and now, in publishing this new book, he and John Howard have attacked the integrity of the nation’s science teachers. Is there nothing and no one that these climate deniers will besmirch in order to deny the basic scientific hypothesis: “That carbon dioxide is increasing, average global temperatures are increasing and that climate change is occurring at an unprecedented historical rate and it is due to human activities”? However, Plimner and his IPA and conservative political mates like Howard, do not attempt to disprove the hypothesis, they simply deny it. They have conducted no scientific research related to climate change and they have published no scientific papers related to climate change in the recognized scientific journals for peer review and scrutiny by recognized climate scientists. What have they done? Nothing. Instead they publish their politically motivated scientifically distorted views in the public media because what they are saying is so scientifically inconsistent that the mainstream scientific media won’t print it. And how do they do it? Make statements like Plimner’s “undersea volcanoes emit more CO2 than humans do”. Do we see the research? Have we seen the Plimner undersea volcano survey with its CO2 measurements from a representative sample of volcanoes? No, we see Plimner’s estimates of what he thinks are the number of volcanoes and how much CO2 he estimates is emitted. Now this type of pseudo scientific research might be enough to fool the popular media but it will not fool reputable climate scientists. Like any good propagandists, deniers of the likes of Plimner (and Carter, Monkton, Spencer, McIntyre, and Lindzen et. al.) will use their scientific credentials gained in other fields and use most of the truth to appear credible but in doing so confuse the scientifically uninformed. In reality, they fail or neglect to clearly explain scientifically; how greenhouse gases can be increasing, how temperatures are increasing, how climate change is occurring, and is having significant impact on the biosphere that we all rely on for life and how all this is natural. Plimner might be a good mining geologist and mining CEO but as a climate scientist, he is a dud.
  9. Ocean Acidification Is Fatal To Fish
    Rob Painting @7, I think it should be made clear that high levels of carbonate and bicarbonate in Norwegian seas relative to current atmospheric levels of CO2 is because of the cold water absorbs more CO2. Therefore colder waters will be more acid for a given CO2 concentration than will warmer waters, as can be seen below: It is not because of unusually high CO2 concentrations in the atmosphere above Norway, or because of local water pollution. At least, that is as I understand the situation.
  10. Ocean Acidification Is Fatal To Fish
    Rosco#6: "natural sources of atmospheric CO2 are far larger than manmade releases." Of course, you are aware that those 'natural sources' have been in place for a long, long time. So long that an equilibrium known as the Carbon Cycle is well-established and well-known. So those 'natural sources' aren't part of this problem; the folks that dumped a large mass of carbon into the atmosphere in under 200 years; more than half of that in the last 60 years - that's the problem.
  11. Ocean Acidification Is Fatal To Fish
    Westerwick @9, I believe Rosco is referring to the fact that CO2 at the Earth's surface is held in three large reservoirs, the upper ocean, the atmosphere and the biosphere. Exchanges between these reservoirs dwarf any additions to the total system by humans. Of course, all three systems are in effective equilibrium, so that net flux between any two reservoirs is close to zero. To increase the amount of CO2 in all three reservoirs requires CO2 from another source, and human emissions dwarf all natural emissions from other sources. Of course, the full facts of the matter have been carefully concealed from (or by) Rosco to create a misleading impression.
  12. The Media & Global Climate Science Communication
    John Hartz @ 16 The quick and dirty answer to your question is that efforts were made in the 1990s to limit the amount of media ownership by another media moghul. While all attention was limiting the extent of the Packer empire, particularly in television, the newspaper market was slowly shrinking. Fifteen years ago most Australian cities had two competing newspapers for consumers to choose from. Now, all but Sydney and Melbourne have only one paper each. Murdoch papers now dominate because the smaller operators have died off. Attention was paid by government to limiting how much of the market a company could buy up but had no answer for how to stop a near monopoly growing by virtue of it's competition witherring on the vine.
  13. Ocean Acidification Is Fatal To Fish
    Rosco--You are correct about CO2 solubility as a function of temperature, but that effect will be totally overwhelmed by the other equilibria considerations. As with any gas-liquid interface with a soluble gas, the system will always attempt to reach equilibrium, and be concurrently losing gas out of solution from the water and absorbing gas from the air. Increased water temperature will shift that equilibrium point to lower net CO2 absorption. In the past century or so, the overall water temperature has increased overall roughly a degree or so. The concentration of CO2 in the atmosphere has increased by nearly 50%. All other things being equal, the net absorption into the water will increase because of the increased concentration and it will try to reach its new equilibrium point based on that, with a slight modification because of increased temperature. Your argument about all CO2 increases due to water temperature increases, well, doesn't hold water (sorry). There isn't enough CO2 in the ocean to "boil off" like that with a small temperature change, aside from the inconvenient increases in the CO2/carbonate/acidity concentrations. If the overall system was that sensitive to temperature, we would see very high CO2 concentrations in the tropics since the CO2 would leave, and very low levels in the northern oceans. In actuality we only see only a couple ppm difference, and most of that seems to be a result of delays in mixing from sources to lower concentration areas. As for "government agencies" and their claims, I think we need to see specific citations and contexts. The natural sources are huge, but when we put the system out of balance and have system response times measured in centuries, it will take time to get back to equilibrium. In the meantime, the climate changes and the oceans become more acidic.
  14. Ocean Acidification Is Fatal To Fish
    fydijkstra many fish are sensitive to even small changes in ph levels even if it doesn't kill them. The question then is whether species would adapt or would migrate. But why conduct a massive experiment with CO2 emissions just to find out what happens?
  15. Ocean Acidification Is Fatal To Fish
    Yvan -"The only problem with this analysis is the CO2 level used are on the extreme high end of the possible" That's not correct. 2300ppm (equivalent) is already experienced over summer and autumn in Kiel Fjord, an area close to cod spawning grounds. This was pointed out in the post. If you look at figure 4 (medium =1800ppm scenario), you'll notice an increase in cod larvae tissue damage and, undoubtedly, a consequent increase in mortality. Also, many regions along the Atlantic coast of North America (home of the inland silverside studied in Baumann [2011]) are seeing acidification much worse than anticipated. In other words, ocean acidification is very likely affecting these fish egg/larvae today.
  16. Ocean Acidification Is Fatal To Fish
    A well established scientific fact - increasing water temperature results in lower solubility of CO2 in the oceans. The net result is less not more CO2 in the water - some well qualified scientists even say the increases in water temperatures observed are responsible for most of the atmospheric increases in CO2 levels. There are numerous references including US government agencies which claim natural sources of atmospheric CO2 are far larger than manmade releases. Either way, no matter what you believe the fact remains - CO2 is less soluble in warm water and rapidly escapes to the atmosphere.
    Moderator Response: [Rob P] Do yourself a favor and read the rather extensive SkS series OA is not OK which is written by actual experts on the topic. The warming oceans will make relatively little difference to CO2 uptake by the oceans.
  17. Roy Spencer on Climate Sensitivity - Again
    CBDunkerson, you should read Spencer and Christi's explanation of what that graphic is, http://www.drroyspencer.com/2011/12/addressing-criticisms-of-the-uah-temperature-dataset-at-13-century/ In a nutshell it is the increase of temperature trend over time (i.e. the world is warming). It is not a graphic showing biases in their estimates (although there were some).
  18. The Media & Global Climate Science Communication
    Yvan Dutil – You misread the tenor of the article. I am definitely not optimistic, but very pessimistic about the way the mass media communicate information. In the print media example cited there was an overwhelming “imbalance” in the media coverage. The statement was made in article “So what message should the mass media be communicating about climate change science?” The mass media is NOT getting the climate science message out – you have to go to specialised media sources for that. The decline of journalistic standards (not the fault of most journalists) is self-evident in the absence of “accurate and unbiased” communication of climate change science. Your example of the introduction of pseudoscience by the media is not an isolated case but typical of the way the industry operates. The article was about highlighting the mass media climate science communication problem - not fixing it!
  19. Ocean Acidification Is Fatal To Fish
    The only problem with this analysis is the CO2 level used are on the extreme high end of the possible. From the data they give, actual high CO2 concentration are not cause by the increase of atmospheric CO2. However, increase of organics matter in ocean due to fertilizer run-off my increase it.
  20. Foster and Rahmstorf Measure the Global Warming Signal
    Interesting link Gerda, it would be even more interesting if they went back to 1900 or so ;) Like their acronym as well, apropos...
  21. littlerobbergirl at 07:00 AM on 22 December 2011
    Foster and Rahmstorf Measure the Global Warming Signal
    thanks utahn, i was thinking that also. it's obviously a tool that can be used for both, as i found a nasa site specifically dealing with smoke http://www.ssd.noaa.gov/PS/FIRE/GASP/gasp.html presumably the natural and man made signals are distinct and easily separable...
  22. littlerobbergirl at 06:53 AM on 22 December 2011
    Foster and Rahmstorf Measure the Global Warming Signal
    maybe something to do with the location on the sensors? e.g. wdca sites seem to be mostly in europe, n.america and africa, none in asia; http://wdca.jrc.it/data/parameters/data_AOD.html which would give good results for background (mostly natural) haze but not human emissions on the timescale and period we are dealing with here?
  23. Foster and Rahmstorf Measure the Global Warming Signal
    skept.fr (and Gerda) I think the links to AOD are found embedded in Tamino's article . Plus you could ask him directly there...I'm not sure if human aerosols get to the stratosphere as easily as volcanic...
  24. littlerobbergirl at 06:42 AM on 22 December 2011
    Ocean Acidification Is Fatal To Fish
    fyd.. and where is that buffer coming from in shallow water where these fish babies are? oh yes, mainly the shells of reef forming organisms. slowly, and patchily. so it's quite possible to get extreme acidity locally, as mentioned in the article. the 'steady state' model just doesn't fit on less than geological time scales or smaller than ocean wide geographical scales.
  25. Ocean Acidification Is Fatal To Fish
    fydijkstra@2 Do you have a link to your paper/study?
  26. The Media & Global Climate Science Communication
    Speaking as a Yank, why on earth did Australians let Murdoch's news empire gain control 70% of the country's print media?
  27. Ocean Acidification Is Fatal To Fish
    The oceans form a pH-buffered system. This means (check your lower grade chemistry lessons) that large changes in CO2-concentration will result in small changes in pH. The present pH-change is insignificant. Predictions of extreme pH-changes are incredible. Not much to worry about.
    Moderator Response: Your comment demonstrates you have not read our extensive OA not OK series. Please read this before commenting further. I consider your comment to be trolling and will delete further trolling without notice. [Doug] [muon] fixed link
  28. Foster and Rahmstorf Measure the Global Warming Signal
    Hi Gerda. I haven't researched exactly how AOD is developed, but I don't think so. Look at Figure 2b above - volcanic eruptions are clear, but there's no indication of human aerosol influences.
  29. littlerobbergirl at 05:42 AM on 22 December 2011
    Foster and Rahmstorf Measure the Global Warming Signal
    oh bother! sorry, didnt read the second page of comments.
  30. Roy Spencer on Climate Sensitivity - Again
    Tristan - that's an interesting idea, though it seems a little mean :-) I wouldn't want to imply that because the UAH trend estimates have been trending upward at 'x' °C per decade, that trend will necessarily continue. The trend might be worth a brief mention though, with that caveat.
  31. littlerobbergirl at 05:38 AM on 22 December 2011
    Foster and Rahmstorf Measure the Global Warming Signal
    hi dana, nice graphs! i get it, only too well. am i right in thinking the optical index will filter out effects not only from volcanic activity, but also from human produced black carbon etc? if so, why no mention? i'm thinking of changing my handle to 'einstein's barmaid' :D
  32. The Media & Global Climate Science Communication
    #6 - While I applaud Julia for what she is achieving, I do wonder if she would be implementing any Carbon Tax if she had a clear majority after the elections. IMO I don't think she would have. Thank goodness for a hung parliment! @14 - You have hit the nail on the head with one of your quotes about the person with the loudspeaker. I find this to be quite common even in basic dialogue with fellow workers. One denialist shouts or yells out loud that AGW is a hoax, so everyone likes to believe him and think he is an expert. Frankly it reminds me of one of my childrens temper tandrums. However as he shouts it out loud I think the average Joe see's this as confidence and therefore believe he must know what he is talking about.
  33. Roy Spencer on Climate Sensitivity - Again
    CBD: excellent graph. It should be added to every post about Spencer and Christy. The entire Post article was a good read.
  34. Roy Spencer on Climate Sensitivity - Again
    Dana, I hope you fit a line to their predictions ;)
  35. Animals and plants can adapt
    The link to Univ of Texas climate change impact article (marked by the text "timing of breeding, migration, flowering, and so on") is broken. It looks like they've moved the article. I think the link was to this article http://web5.cns.utexas.edu/news/2004/11/global-warming-2/
  36. The Media & Global Climate Science Communication
    @JH Not off topic at all, when it is presented as a clear example of the problems that we are facing with respect to accurate and effective communication by the media. The guy with the loudspeaker trumps all voices. Especially, with all the social media noise. I like the saying "Death by data", where you generate so much irrelevant data for a project that in the end you don't have time to analyze or even find the relevant data. The same is true with information : "Death by information". That is the problem that social media have generated for people that do not have the time, the will, or event the tools (mental or otherwise) to collect, analyze, draw conclusions etc. I despair looking at the fact that politicians, forming the policy for the response or not to global warming, are IMO at a low point with respect to the quality and accuracy of information that are fed to them by their underlings.
    Moderator Response: [JH] With all due respect, you re-posted a statement made by a climate denier on a comment thread to an article. The original post is about how the mainstream media in Australia covered climate change policy-making in Australia.
  37. Roy Spencer on Climate Sensitivity - Again
    Yes, look for our response to the UAH 33rd anniversay release, probably on Monday.
  38. Roy Spencer on Climate Sensitivity - Again
    CBDunkerson @27, Agreed. Spencer and Christy have way too much confidence in their product. Other satellite products such as STAR show much greater rates of warming in the mid-troposphere than do UAH and RSS. So to claim that the satellite data are the gold standard or the benchmark for global temperatures is just plain wrong. This was a pretty blatant PR exercise and misinformation campaign by Christy and Spencer-- and I suspect that we will keep hearing them repeating the same debunked myths each year. They seem to be under the impression that if they keep repeating falsehoods they will become true. That was a pretty good article by Freeman, good for him for calling Spencer and Christy on their misinformation. But no worries, SkS is on the case and will have something posted soon :)
  39. Foster and Rahmstorf Measure the Global Warming Signal
    #53 KR : I agree with your presentation of FR2011, the near-linearity of the signal suggest residual noise (if any) is probably weak. But the fact that there is no acceleration in the trend could also suggest that there is a residual natural cooling noise in the past decade (and/or warming in the previous). If so, the AGW rate would accelerate in reality. I don't know, but I'm pretty sure FR2011 cannot be interpreted firmly in a "reassuring" way (you know, interpretation like "don't worry, warming rate is steady, it proves that we will get 1,7 K in 2100 in BAU scenario"). #dana1981 : the anthropogenic sources of aerosols is supposed to have decreased in the 1980-1990s (works of Martin Wild and co-authors on "global brightening"), then increased in 2000s due to global increase of coal plant emissions (Chinese and emerging countries). (So again, one should note this a cooling trend in the 2000s decade.) Is there a reference web source explaining how the AOD is calculated (methods, sites, etc.)? For example, I don't know how the indirect effect (in cloudy sky) can be measured.
  40. Ocean Acidification Is Fatal To Fish
    Really good post Rob, but rather disturbing that we keep finding new unintended consequences of anthropogenic climate change. A lot of people rely heavily on fish for food - decreasing stocks due to acidification would be really bad news.
  41. Foster and Rahmstorf Measure the Global Warming Signal
    dana1981 - I agree on the human aerosols. I suspect our data on the subject (given the regional nature and short lifespan of human aerosols) isn't terribly good, but I've suggested the same over at Tamino's blog. In the meantime, I don't think F&R have in any way claimed that these are the only exogenous influences on climate - simply that they are large ones, and that accounting for them improves our view of GHG influences.
  42. Foster and Rahmstorf Measure the Global Warming Signal
    Agreed with KR @53 - this paper certainly doesn't remove all exogeneous factors, just 3 big ones (3 of the biggest, in fact). The one criticism at WUWT that I'd like to see implemented is the influence of human aerosol emissions. That would make for an interesting addition to the analysis, if we could get good enough emissions data.
  43. Foster and Rahmstorf Measure the Global Warming Signal
    skept.fr#52: "The 2000s decade could well have been the definite proof that natural factors are henceforth unable to cool the Earth, even in the most favorable condtions for that." Fair point. I noted here that quiet solar conditions (a natural variation if ever there is one) were ideal for the onset of cooling; F&R's important result show no evidence of that happening. But surely the pseudo-skeptics will cry, 'wait 'til next year!'
  44. Foster and Rahmstorf Measure the Global Warming Signal
    skept.fr - As I (personally) interpret F&R 2011, the purpose of the paper was to remove large, known sources of variability from the temperature signal, and see how they affected the statistical relevance of an underlying warming trend. Hence their regression against ENSO (known to affect temperatures, with at least a partially understood physical basis for those effects), volcanic/sulfur aerosols (simply on the basis of albedo), TSI (goes without saying), and the annual cycle. The results indicate a very strong agreement among the five temperature records, a clear linear trend, and greatly reduced variability in that identified trend. In addition the correlation strength and lag times are quite interesting, and match reasonable expectations of the physical basis for their effects on temperatures. Remaining variability may be (I would almost say "would have to be") due to other effects. But - given the statistically linear residuals of the data after these components, these other potential influences do not show a cyclic effect, or for that matter a dominant effect, on the data that we have so far. Perhaps after some time, with more data, we might have enough to tease out other cyclic or acyclic influences on temperature. Right now, with the data used in the F&R paper, limited by (among other things) the length of the satellite record - there's little evidence for it.
  45. Foster and Rahmstorf Measure the Global Warming Signal
    Tom : thank you. Bert : read my first message in #13, my point was clear about signal-noise disambiguation, and my conclusion was clear too : "I think FR get the broad picture with their choices, but I don't know if the decadal trends they obtain from their removals are very precise. Maybe lower, maybe higher." (My emphasis). In my opinion, if multidecadal unforced variability exists and is assessed, the real AGW signal may well be higher (not lower) that the conclusion of FR2011. For example, if you look at this recent Douglass guest post on Curry's blog, you see that the author suggests the internal variability modes could have known a very low shift at the beginning of the 2000s, the lowest of the past 70 yrs (figure 1 from Towsley et al 2011). If he is correct (that I don't know, and remind this is just a blog post without real scientific value), it would mean that instead of a slight warming, and the warmest T from instrumental records, past decade should have known a very sharp cooling. So, maybe we underestimate (even FR2011) the real signal of AGW in climate. That is why even people who refers to the sun or the natural variability, frequently in a perspective of denialism, doesn't understand the real implication of what they advance for climate. The 2000s decade could well have been the definite proof that natural factors are henceforth unable to cool the Earth, even in the most favorable condtions for that. And this would be quite a bad news for all us. You must really keep an open mind on all these questions. I'm skeptic, not denier.
  46. The Media & Global Climate Science Communication
    I don't share your optimism about the effectiveness of a good communication strategy. I have a Ph.D. in astrophysics and have given a countless number of interview. Many time, an astrologer was invited in the same news report to give a "balanced" view. In addition, I dis some science journalism. I can confirm, there is ZERO time to check your sources. Even putting things in context is very hard due to the limited amount of space.
  47. Roy Spencer on Climate Sensitivity - Again
    Spencer and Christy are at it again, using the 33rd anniversary of the satellite record to repeat their claims that their satellite records 'disprove' climate model projections and that the observed warming is therefor mostly 'natural variability'. A Washington Post article on these claims included a great rebuttal in image form; This was apparently created by John Abraham and sent to them by Andrew Dessler. In any case, I hadn't seen it before and it really brings home just how many serious problems there have been with Spencer & Christy's work and how they have consistently been biased in one direction. The temperature trend Spencer & Christy show now is more than 0.2 C per decade higher than their original claims. If we apply that as a 'demonstrated uncertainty range' around their current claim then the possible spread on their current value includes warming much greater than any of the mainstream projections.
  48. Foster and Rahmstorf Measure the Global Warming Signal
    Bert @50, while I may be disappointed in the end, on evidence to date I do not think you have skept.fr's measure at all. He is not a carbon copy denier, and should not be treated as one. Further, suggestions that he has simply trying to distract us from the obvious are not helpful.
  49. Bert from Eltham at 21:10 PM on 21 December 2011
    Foster and Rahmstorf Measure the Global Warming Signal
    skept.fr The core of your question is now differentiating signal from noise?! I will say this very simply that the eddies in the flow of heat have been subtracted from the measured signal by FR 2011. These are real perturbations of the GTA caused by both the drivers and mediators apart from our CO2 pollution. The resultant signal is our contribution to the temperature increase of SpaceShip Earth You are complicating what is a simple scenario by pointing to red herrings. I reckon I have your measure. Bert
  50. Foster and Rahmstorf Measure the Global Warming Signal
    skept.fr @48:
    "Tom : only one such "oscillation" has a proven effect on global climate - ENSO I think we disagree on this point, because I consider there is a debate in climate community."
    You misunderstand me. There is debate about the effect of several of these oscillations on global temperatures, most particularly the AMO and the PDO. But for just one oscillation has the debate moved to the point where it is beyond reasonable dispute that that oscillation effects global temperatures, ie, for ENSO. For all other candidates, you will find evidence and scientists on both sides of the debate.

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