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Comments 88151 to 88200:

88151. Albatross at 02:43 AM on 18 April 2011
       What was it like the last time CO2 levels were this high?
       [inflamatory comments deleted] I'm far more interested to know whether or not we have a good idea how much ice there was before the temperatures started rising during the Pliocene? Also, a recent study claims that the current CO2 levels are the highest in 15 million years, see here. If that is true, as are the findings discussed by Bart Verheggen here, then I really do not see much reason for the optimism and glib attitude shown by our dear contrarians.
       Moderator Response: [Dikran Marsupial] Please see the comment on Villalobos' post; the discussion is best served if we all keep the tone neutral, whatever the perceived provocation.
88152. Gilles at 02:42 AM on 18 April 2011
       More Carbon Dioxide is not necessarily good for plants.
       "The initial post contains reasons, references, and data supporting the premise" AFAICS, the initial posts contains a short list of possible reasons that could go worse. This is neither exhaustive, nor limitative. There is no figures associated. No possibility of doing any budget. No experimental validation on a global scale. I can't see how to draw a general conclusion from that ..
88153. Gilles at 02:39 AM on 18 April 2011
       More Carbon Dioxide is not necessarily good for plants.
       KT there is no assertion - except I'm surprised by the general result - that everything goes wrong. Obviously agriculture is a complicated aggregation of several things , very variable locally - temperature, rains, ground chemical composition, CO2, parasites ... Under some conditions, CO2 is actually used to improve the growth. So you wouldn't expect that a CO2 increase is bad *everywhere* Do you think that God hates us so much ?
88154. Albatross at 02:33 AM on 18 April 2011
       Debunking Economic Myths from the Climate Hearing
       WSteven @12, "I know that they've done some things, but the Conservative Party of Canada still have a long ways to go" Too true. There have been some attempts at green washing, but not much else. Some huge oil sands projects will be coming on line soon. The projections for oil production from the tar sands are up and up and up (I need to substantiate that I know, will do that, but I happen to know people on the "inside"). And let us not forget that Harper et al. are mostly from the old Alliance party....scary. That said, let us not write them off, but let us be realistic. Someone needs to hold their feet very close to the fire. It could be that Canada faces sanctions of some sort down the road....you never know, but that is what it might take. Either way, to get back to the topic of this post, it seems to me that the uncertainties in the economic models are far greater than those form the climate models, yet some consistently try and use some obscure economic figures to claim devastating economies and the such so as to encourage FUD. The interesting thing about economic models, the results are dependant on the many assumptions that you need to make. Someone managed to demonstrate that buying a hummer was actually better for the environment than a Prius (sorry cannot recall the details), and they did, but had to choose some wildly unrealistic assumptions to do so. Climate models ont he other hand are constrained by physics, yes their is uncertainty, but one cannot assume that pi=4.0 or "tune" the stefan-Boltzmann constant or the radiative forcing from each GHG. And what is more, one can quantify the uncertainty. With that all said, what we need are more full cycle studies and more studies which incorporate the social and environmental costs of using the available energy sources, such as the paper Dana discussed on the SCC.
88155. Rob Honeycutt at 02:33 AM on 18 April 2011
       It warmed just as fast in 1860-1880 and 1910-1940
       Excuse me... Four periods that were statistically significant.
88156. Rob Honeycutt at 02:29 AM on 18 April 2011
       It warmed just as fast in 1860-1880 and 1910-1940
       Andrew... He provided three trends that were statistically significant. That's not the same.
88157. witsendnj at 02:29 AM on 18 April 2011
       More Carbon Dioxide is not necessarily good for plants.
       I often use the analogy of extra calories. How's that McDonalds diet working out for the average American's health? I agree that a simplistic view that rising CO2 is good for plants, without taking into account other nutritional requirements not to mention the effects of climate change on trees is a willfully obtuse denier tactic. On the other hand, the FACE experiments do show increased growth in the field, as does this study from the Smithsonian. http://www.sciencedaily.com/releases/2010/02/100201171641.htm Unfortunately, what the FACE results find, and my own investigation into that Smithsonian research (posted here http://witsendnj.blogspot.com/2010/04/serc-sucks.html) indicate is that any boost in growth is more than offset by stunting from concurrent rises in the level of background tropospheric ozone. Ozone results from the same processes of burning fuel that produce CO2 and climate change. Ozone is itself a greenhouse gas but even more significantly, it is toxic to vegetation. It reduces annual crop yield and quality by anywhere from 20% to 80%, according to various international agencies, making this an urgent problem right up there with ocean acidification. Trees exposed to cumulative damage season after season are dying at a rapidly accelerating rate. Without trees as CO2 sinks, climate change will lurch ahead in very hazardous ways. Many studies link increased damage from secondary attacks from insects, disease and fungus as well as storm and drought to ozone, not CO2. Here is an excerpt from an article about FACE (Free Air Carbon Dioxide Enrichment) program in Wisconsin: http://www.admin.mtu.edu/urel/news/media_relations/49/ The trees of the future may be much more vulnerable to a variety of pests, say scientists studying greenhouse gases in northern Wisconsin forests. Their work is published in the Nov. 28 edition of the journal Nature. Researchers in the Aspen FACE (Free-Air Carbon Dioxide Enrichment) Experiment, based in Rhinelander, Wis., have been measuring the effects of elevated levels two greenhouse gases, carbon dioxide and ozone, on aspen forest ecosystems. While the trees, Populous tremuloides (trembling aspen), seem to do relatively well in a carbon dioxide-rich atmosphere, ozone is another story. Trees growing in an ozone-enriched atmosphere have been hit much harder by their traditional enemies: forest tent caterpillars, aphids and the rust fungus Melampsora. "This has been a surprise," said Professor David Karnosky of Michigan Technological University's School of Forest Resources and Environmental Science, a principal investigator on the Aspen FACE project. "Our experiment was never meant to look at pest occurrence. But it became obvious that the greenhouse gases were affecting the abundance of pests." Ozone seems to be a special blessing to aphids. Not only did the tiny insects thrive in high-ozone air, populations of aphids' traditional predators--such as ladybugs and spiders--plummeted. "The aphids had free rein," noted Caroline Awmack, an Aspen FACE researcher from the University of Wisconsin, Madison, Department of Entomology. Studies have shed some light on why the aspen growing in ozone-rich air were turning into so much bug salad: their leaves seem to be undergoing fundamental changes. "Ozone alters the surface waxes," said Kevin Percy, a research scientist with Natural Resources Canada--Canadian Forest Service, who is the lead author of the Nature article, "Altered Performance of Forest Pests under Atmospheres Enriched by C02 and O3." The number of aphids increased about five-fold in plots with elevated ozone, while the number of aphid predators was cut in half. In plots with elevated levels of both carbon dioxide and ozone, the aphid population tripled, while the number of natural enemies increased slightly, mitigating the aphids' effect on the aspen. Melampsora infection in the control and CO2-enriched plots was about the same, but increased about 400 percent in the O3 plots and doubled in the plots with extra CO2 and O3. The number of forest tent caterpillars increased by about one-third in the O3 plots and actually decreased slightly in the CO2 plots and the plots with extra CO2 and ozone. Links to more research can be found here: http://witsendnj.blogspot.com/p/basic-premise.html
88158. Albatross at 02:13 AM on 18 April 2011
       Muller Misinformation #3: Al Gore and polar bears
       Chris @11, Here you go.
88159. KR at 02:11 AM on 18 April 2011
       More Carbon Dioxide is not necessarily good for plants.
       My oh my, Gilles - your trolling is becoming more and more blatant. The initial post contains reasons, references, and data supporting the premise. Your post contains vague handwaving, zero references, and indicates that you have either not read the initial post or references, or are completely and deliberately ignoring them. Assertions without evidence can be dismissed without evidence - your post is content free, trolling, and should be treated as such. DNFTT.
88160. Gilles at 01:45 AM on 18 April 2011
       More Carbon Dioxide is not necessarily good for plants.
       I wonder why Nature has managed to make an increase of average temperature bad for everything. Isn't it quite unlikely ? especially for agriculture, it is quite weird because each plant has a favorite biotope, so the productivity cannot be a universal decreasing function of the local average temperature. So it must be somewhere optimal. But changing temperature should only displace the location of the optimum. Well it could be that this displacement is unfavorable, but also it could be the opposite. How do you explain that it seems to be *universally* unfavorable, everywhere? and if not, how can you properly compute an average trend, and know whether the benefits are larger than drawbacks or the opposite ? you seem to possess some kind of science I'm totally ignoring ....
88161. KR at 01:28 AM on 18 April 2011
       It's albedo
       RW1 - "Remember, I agree the physics supports a likelihood of some effect (i.e. some warming) from 2xCO2. I'm mainly disputing the magnitude of 3C predicted by the AGW hypothesis." About 1.1C from a doubling of CO2, estimate of about 3C from feedbacks, so this is an issue you have with feedbacks, best addressed on the relevant How sensitive is our climate thread. It's well worth keeping in mind that this is a boundary value issue. Increasing greenhouse gases barely affect incoming radiation at all, but greatly reduce outgoing radiation. Equilibrium isn't reached until the outgoing matches incoming. And that is what drives surface temperature changes.
       Moderator Response: Yes, and not just "best" addressed, but "must" be addressed on that other thread or other threads that are more appropriate than this.
88162. Alec Cowan at 01:16 AM on 18 April 2011
       The e-mail 'scandal' travesty in misquoting Trenberth on
       @Ken #129 uhu? I don't think so. The fact is it looks that the new treasure hunt is getting a paper that states a cooling-warming of the oceans from any 4 or 5 years in a row within the last decade that states an average from -2 to 1.6W/m² in 0.05 increments. It's just a matter of time -and a research of academical resources including those outside public access WWW- that you'll find the paper with the value of your choice. The Knox & Douglas paper was why I suggested -to others- the exercise in #128 -the exercise predates the paper-. I have to thank you for that paper because it's now in my database for critical thinking in Statistics. Take a look to figure 1 there and tell me what you see. Neither BP nor you contributed one of many papers revealing a heat gain in deep oceans for recent years, specifically in southernmost basins. Why? Is some cherry-paper picking out there? Some kind of "editorialized" line of evidence? The papers I was referring in a previous comment are related to the travesty as Trenberth meant it. The papers you picked are related to the a supposedly independent line of evidence "confirming" the 'climategate' paraphernalia. The matter continue to be "the travesty", as that's the topic of this post and these comments. I suppose people interested in that already discussed the real cooling parts -there are those, I've been discussing about that since 2007- of the supposedly cooling trend and what causes it, all within the other post you listed.
88163. muoncounter at 01:08 AM on 18 April 2011
       It's not bad
       Gilles#113: "since the average population, ... growth has been positively correlated to temperature" Seeing something in such correlation is specious at best; at worst, it leads to yet another faulty conclusion based upon simple-minded extrapolation. One could just as easily say that population growth correlates well with a stable range of temperatures, or more importantly, a near-zero rate of change of temperature. Once out of that range or in excess of that rate of change, you have no further correlation. Another factor that is obscured by your faulty use of correlation is how interdependent the world is now. During the LIA for example, malnutrition in Europe did not necessarily impact the quality of life in Central Asia. In today's world, a problem in one continent has drastic implications on conditions around the world.
88164. chris1204 at 00:55 AM on 18 April 2011
       Muller Misinformation #3: Al Gore and polar bears
       According to the World Wildlife Fund (2009): Several polar bear populations were decimated by unsustainable hunting by European, Russian and American hunters and trappers from the 1600s right through to the mid-1970's. In 1973 commercial hunting was strictly regulated following the signing of an international agreement on polar bear conservation. Moreover: Today, polar bears are among the few large carnivores that are still found in roughly their original habitat and range, and in some places in roughly their natural numbers. Although most populations have returned to healthy numbers, there are differences between the populations. Some are stable, some seem to be increasing, and some are decreasing due to various pressures. There are large uncertainties regarding some populations that are still harvested quite heavily and others for which information is lacking. As you can see from their map, which you can access on the World Wildlife Fund site (alas, my best efforts to post the image have been to no avail): 1 population is increasing, 3 populations are stable, 8 declining, and 7 data deficient. I don’t question the consensus that habitat loss would be a major threat to bear numbers at least in areas in which hunting is strictly controlled because polar bears strong preference for hunting seals on sea ice. A recent Nature study, for example, predicts decreasing litter size with earlier sea ice melt in west Hudson Bay suggesting this could affect about 30% of the polar bear population. However, the authors sensibly caution that much depends on assumptions about sea ice behaviour, discussion of which clearly belongs on another thread (but yes, I do know Hudson Bay did not freeze over completely last winter). Moreover, their study is based on predictive modelling flowing from the observation that approximately 28% of pregnant females failed to reproduce for energetic reasons during the early 1990s. They note: Historically, polar bears came ashore in early August, but because of rising temperatures sea ice break-up has been occurring about 7–8 days earlier per decade in recent years. Polar bear on-shore arrival has shifted accordingly, resulting in shortened on-ice feeding and prolonged on-shore fasting. The authors also note limitations in their study: However, on-ice feeding rates are unknown for Hudson Bay, and it is also unclear how these rates vary seasonally. They then acknowledge assumptions in their modelling which might both overestimate and underestimate litter sizes. Returning to our map, I note that the west Hudson Bay population is declining but the adjacent Southern Hudson Bay population appears stable. The disparity between adjacent regions suggests the whole business might be complex than at first sight. Historically, the climate even in the West Hudson Bay area has shown considerable variability. Hence, Dyck et al (2007) write in Ecological Complexity: Finally, we wish to encourage a renewed archaeological search for information related to polar bear population ecology from 1760 to 1820, when historical evidence (based on early thermometers at trading posts of Churchill Factory and York Factory) suggests that the climatic regimes at WH had shifted from temperate to arctic conditions …. Ball (1983, 1986) documented large changes and abrupt shifts in both floral (i.e., treeline boundary between the boreal forest and the tundra) and fauna (i.e., migration of wild geese) ecosystem responses of the Hudson Bay region that occurred naturally as a consequence of the varying mean locations of the Arctic Front …. I appreciate that some of the authors of the latter study, which is also a little old, might not be universally popular on this site but so be it.
88165. Tom Curtis at 00:15 AM on 18 April 2011
       A Flanner in the Works for Snow and Ice
       Ken Lambert @73, during the summer months of 2010, there was (more than) 2 million square kilometers less ice than during equivalent summers thirty years ago. The sunlight falling on water that would have fallen on ice in 2010 did not heat the water over the intervening years. It only heated it in 2010. Therefore there is need to divide the 1.51*10^21 Joules by 32. That is the additional amount of energy each summer that would not have been absorbed except for the reduced sea ice area.
88166. Dikran Marsupial at 00:13 AM on 18 April 2011
       Video on why record-breaking snow doesn't mean global warming has stopped
       Gilles@21 Firstly, it is steerable, all we have to do to see A1F1 is to carry on doing just what we are doing now. Secondly, for falsifiability, it doesn't have to be steerable (e.g. Eddington's corroboration of Einstein's theory of relativity, neither Einstein nor Eddington control the positions of stars or planets). Thirdly, it doesn't have to be A1F1, if temperatures fall over the next century by say a degree or more below the lower error bar of the most appropriate scenario, that would falsify AGW theory. As the models have been published, you could even in 2100 put the observed forcings into the model and AGW theory would be falsified if the observed rise in temperature was (say) a degree less than the lower error bar. It isn't hard to come up with a falsifiable test, of AGW, simply because it makes a lot of predictions.
88167. Alec Cowan at 00:07 AM on 18 April 2011
       Clouds provide negative feedback
       #18 ERRATUM: Where it say "No, it'll clearly sink." it must say "No, it'll clearly float."
88168. RW1 at 00:01 AM on 18 April 2011
       An Even Cloudier Outlook for Low Climate Sensitivity
       Dessler seems to be claiming that clouds are trapping more energy as the surface warms. He writes on page 3 of his paper: "Because I have defined downward flux as positive, the positive slope here means that, as the surface warms, clouds trap additional energy; in other words, the cloud feedback here is positive." Is he claiming that clouds are changing in a way that results in them trapping more surface energy? If yes, how has he rectified this with all the data (i.e. how has he shown that the additional energy the clouds trap is greater than the additional energy they reflect away)???
88169. Glenn Tamblyn at 00:00 AM on 18 April 2011
       Last day to vote for Climate Change Communicator of the Year
       Reminds me of an old Footrot Flast cartoon (for those who don't know it, it tells you more than you could ever want know about rural New Zealand, centered on a sheep dog called simply Dog) Dog is watching a pig give birth to a litter of piglets, all very excited about it as he counts them out. "One....Two....Uhm....LOTS AND LOTS" Get those votes in People!
88170. Alec Cowan at 23:56 PM on 17 April 2011
       Clouds provide negative feedback
       @RW1 9of17 comments to this post, so far. You are likely to get soon a DNFTT banner in your comments and I'd like to explain why is that. T - "If I throw this stone into the water it'll float" P - "No, it'll sink, stone's density is higher that water's" T - No, it'll clearly sink. Don't you see the weight of the stone is less than the weight of the water, you, idiot? M - DNFTT You might think that the trolling part is "you, idiot", but that is clearly just something said on the heat of the debate and doesn't affect the intellectual content of it, so it's easily dismissed. The trolling part is simply the underlying lie about the world of Physics: the twisted pricipia that things float if they amount a lesser weight. The "no" and the "you, idiot" part just reinforces the idea that the troll has made his/her mind -nobody cares about how or why- and he/she's simply "trolling around". I suppose that many fellows who think that there's a "global warming hoax" of some kind, sort of they come to websites like this "to get our voices heard about that outrageous subject", and that they experience comforting feelings if they overflow threads and the comment sections and then get a trolling banner just for "hitting the nerve" and as a result of "the nuisance their witty remarks provoke". Please, don't fool yourself with such naïvités. You're in an academical site and you have the ethical obligation of being diligent in detecting or correcting any wrong product of you animus. It also happens that the fact that you detect the gruesome mistake in the 'floating' example doesn't mean you are not gruesomely mistaken just because you cannot detect it. The principle for (legally) capable people that states "nobody can argue his own slowness and clumsiness to justify an error" comes from that obligation of diligence. In sites like this it translates in a diligent revision of your knowledge matrix once it has being pointed at you gruesome conceptual mistakes. The worst thing it could happen is that you learn something.
88171. Gilles at 23:49 PM on 17 April 2011
       Video on why record-breaking snow doesn't mean global warming has stopped
       DM :"So here is a directly falsifiable test: Follow A1F1, if temperatures in 2100 are lower than they are now," yes but the scenario is in itself not steerable - so what you propose is mainly a counterfactual test . Can't you propose a test valid for any scenario, and if possible, soon enough ? if you can't , it means that all AGW "theory" is still in a state of hypothesis ...
88172. Adam at 23:41 PM on 17 April 2011
       It warmed just as fast in 1860-1880 and 1910-1940
       He also provided the data, which showed the warming rates were the same. You can clearly see it below Phil Jones' statement.
88173. Adam at 23:40 PM on 17 April 2011
       It warmed just as fast in 1860-1880 and 1910-1940
       PPS: logicman he is saying that the difference between the rates of warming for the three periods of warming are not statistically significantly different from each other i.e. the rate of warming was the same for each one. Saying the rates were statistically significantly different would have confirmed what was said in this post, but he did not say that. He simply admitted there is no statistical difference between the three periods of warming. I'm not entirely sure what you're trying to show in your comment logicman.
       Moderator Response: [DB] "i.e. the rate of warming was the same for each one." Making this leap is where your logic fractures. [Dikran Marsupial] In this context, the test of statistical significance basically implies only that we can't rule out the possibility that the rates are the same, not that they actually are the same. Tests of statistical significance are conceptually rather subtle, and widely misunderstood, even amongst scientists and even statisticians!
88174. Ken Lambert at 23:15 PM on 17 April 2011
       A Flanner in the Works for Snow and Ice
       Tom Crtis #73 Did you divide your 1.51E21 Joules by 32 years (1979-2011) to get the annual extra energy absorbed in Joules/year to compare with Dr Trenberth's number of 1E20 Joules/year? If you do that, you get 0.49E20 Joules/year - very conservative but in the ballpark?
88175. Ken Lambert at 23:06 PM on 17 April 2011
       The e-mail 'scandal' travesty in misquoting Trenberth on
       Alec Cowan #128 Suggest you read through the contributions of BP and KL and others from this thread, rather than my repeating complex arguments: http://www.skepticalscience.com/Climate-cherry-pickers-cooling-oceans.html Note particularly the issue of a 'gold standard' of tethered buoys all over the planet as a comparison for Argo. The issue is that Argo coverage is far better than XBT or prior methods and as full deployment has proceeded and problems rectified, the heat content increase has flattened, zeroed or (in the top 700m) cooled. viz. the Knox & Douglas paper referenced earlier.
88176. les at 23:03 PM on 17 April 2011
       Video on why record-breaking snow doesn't mean global warming has stopped
       18 - batsvensson regarding "extended snow cover will increase the heat flux out from the earth surface and cause global temperature to decrease" The onus is on you to show or find papers which show that this follows. To me, it's not obvious. Calculating the impact on "heat flux" - I guess, how much more or less energy is radiated / reflected - due to extra snow fall in the north needs some work. I know where I live (about 64°32'N) where it's snow covered almost 5 months a year, extra snow fall won't make much difference. On the one hand the ground is already mostly white; I'd guess the snow keeps the ground warm (white doesn't radiate as much as black). On the other hand, it's dark, the snow reflects very little sunlight - there is very little sun light to reflect! That's during the winter - at the 'margins'... will there be extra days of snow cover or fewer? etc. All has to be calculated. Other parts of the world would differ to here. Will there be substantial snow cover where there was none? Or longer snow cover? Will that reduce the rate of cooling? Or reflect more sunlight? You have to be able to estimate how much extra snow and the impact of that, if any. maybe someone's done some estimates, may you'd like to give it a try! ... certainly you cannot jump from "there will be more snow falling in the north" to "there'll be an ice-age"! Looking forward to seeing the fruits of your research.
88177. Bob Lacatena at 22:37 PM on 17 April 2011
       Clouds provide negative feedback
       RW1, No. You misunderstand, and then cling to your misconceptions. You need to spend less time lecturing, and more time reading and studying, to figure out for yourself where your own mistakes are. End of "debate."
88178. JMurphy at 22:36 PM on 17 April 2011
       Video on why record-breaking snow doesn't mean global warming has stopped
       batsvensson, I haven't a clue where you get the "personal attacks" belief from, but if that is what you see, it isn't what I intended. Is English your first language ? If not, perhaps that is where the difficulty is. Anyway, no personal attacks intended. But, with regard to your original question : Did any one propose, say, 10 years ago that snowing will increase when the climate warms up? I think you should have seen by now that the answer is 'Yes'. Yes ?
88179. johnd at 22:36 PM on 17 April 2011
       CO2 is plant food
       Villabolo, making an argument that CO2 is merely plant food is understating the fact. Carbon is a fundamental building block for all life forms, plants being about 45% carbon, whilst animals including humans are less than 20%. Interestingly, by comparison the carbon content of coal ranges from about 30% in low rank coals such as lignite to 45% to 85% for the most used form of bituminous coal, up to to 98% in anthracite. However what I am interested in is the statement "Higher concentrations of CO2 also reduce the nutritional quality of some staples, such as wheat." Are you able to quantify both the reduced nutritional quality along with any associated increased yields as determined by the better performing varieties that have been tested in open field trials under enriched CO2 conditions?
88180. Gilles at 21:33 PM on 17 April 2011
       What was it like the last time CO2 levels were this high?
       OK but am I allowed to answer villabolo's points or not ?
       Moderator Response: [Dikran Marsupial] As long as you stick to comparison of climate yes; if it relates to whether the change will be bad for mankind, respond to them on "its not bad", where they would be more appropriate. Please also pay attention to the comment I left on Villalobo's post.
88181. Dikran Marsupial at 20:25 PM on 17 April 2011
       It's not bad
       Gilles@113 First, as was pointed out on the previous thread, correlation does not imply causation. A more likely explanation for rising population and rising temperatures is that they both share a common cause, namely increasing economic growth through exploitation of fossil fuels. Economic growth leads to better nutrition and healthcare, which supports a larger population. Fossil fuel use leads to carbon dioxide emissions that you have said you are prepared to accept leads to warmer temperatures (how much we can leave for the climate sensitivity thread - not to be discussed further here). Of course an increase in population leads to greater fossil fuel use, greater carbon dioxide emissions and hence higher temperatures. So if anything the causal arrow goes from population growth as the cause to temperature increase as the consequence, rather than the other way around. As to your particular question, see the work of Malthus. Populations grow until they reach the limits of what the environment can support. Agriculture, improving health care, fossil fuels have all led to increased population and prosperity. That doesn't however mean that increase continues indefinitely. If climate change leads to a disruption in agriculture (for instance), then the Malthusian limit gets pushed back and we end up with at least part of the world population subject to famine. It seems to me to be quite likely that the world population is close to or at the Malthusian limit already, which is why climate change is likely to be a big problem. In short, temperature rise is no great problem for human population growth provided (i) it is not too rapid for easy adaption and (ii) the population is not close to its Malthusian limit already (that is the point where the correlation is likely to reverse). As to what we do about it, personally I would say we can't do anything quickly about population levels (doesn't fit in with my idea of ethics anyway!), so the obvious thing to to is to try and prevent the Malthusian limit on population being brought down by climate change by limiting our fossil fuel use in order to prevent great hardship (mostly in the third world). Of course that won't be pleasant for any of us, but it is better than the alternative.
88182. batsvensson at 19:59 PM on 17 April 2011
       Video on why record-breaking snow doesn't mean global warming has stopped
       JMurphy wrotes: "Secondly, you shouldn't rely on outdated ideas, especially since the site I linked to continues" Does this imply that you reject the idea that an extended snow cover will increase the heat flux out from the earth surface and cause global temperature to decrease or have I missed something here?
88183. batsvensson at 19:46 PM on 17 April 2011
       Video on why record-breaking snow doesn't mean global warming has stopped
       "But you seem to have ignored the UCSUSA link..." etc... You asked me what lead me to such understanding with out this I answer you assuming nothing. However you seams to have taken my answers as an opportunity to followed up with personal attacks on me. I would suggest you try keep to the subject instead and not discuss my person or knowledge base.
88184. batsvensson at 19:37 PM on 17 April 2011
       Video on why record-breaking snow doesn't mean global warming has stopped
       JMuphy, clearly your understanding of what constitutes a prediction is fundamentally different from mine but I see no point in discussing that issue any further here. My understanding is that global warming is attributed as cause for the recent increased snowfall. Assuming this understanding being correct, is there any other possible cause for this and if so what reason do we have to exclude those explanations as causes for the increased snowfall?
       Moderator Response: [DB] Where I live (in the northern snow belts of the Great Lakes of North America) snowfall totals have been down significantly for the last several years. So increases are not necessarily global or even regional.
88185. Dikran Marsupial at 19:15 PM on 17 April 2011
       Climate sensitivity is low
       Gilles wrote: "I am completely ready to admit that CO2 contributes to warm the atmosphere , on very simple arguments of radiative transfer. My only questions are quantitative." This is the best place to have such questions answered; I am sure there are plenty of knowledgeable posters here who would be happy to answer them for you.
88186. villabolo at 19:00 PM on 17 April 2011
       What was it like the last time CO2 levels were this high?
       @42 Moderator: "Moderator Response: [DB] Your spirit is appreciated, but your energy is better served someplace where productive results are achievable. Unfortunately, this is not one of those. DNFTT" Please Moderator; I promise to stop the feeding frenzy. From now on I beg you to bind and gag me whenever he posts! **************************************************** @43 Gilles: One last time through this Gish Gilles Gallop and then I'll stop beating these dead horses: Now i'm rather stupefied by the number of false and unsubstantiated statements I can read in your answers - it's unfortunately a little bit lengthy to answer all, so please forgive me if I forget some. "the obvious prospect of severely escalating problems in the future." : well obvious if you believe in them, and if you're formatted by the impressive number of dire predictions that are made everywhere - but actually there is no "obvious" fact about an imminent catastrophe. recent example drawn from a competitor site http://asiancorrespondent.com/52189/what-happened-to-the-climate-refugees/ maybe we'll soon have here a post on this subject ? "Obvious" is based on deductive reasoning based on a wide assortment of facts that you seem to be ignorant on. "You are concentrating on a natural event that is sporadic in a given time period versus human distorted 'natural' events which are increasing on a year by year level." ... which human distorted natural events are increasing on a year to year level ? well , they're probably "human distorted" but not quite in the same sense ... (As I let out a loud sigh). The escalation in temperatures during the last several decades; increase in rain intensity...Deja vu, am I repeating myself? Never mind Gilles. "Besides, you have not responded to the issue of Arctic Ice cap shrink and its effects in the near future. " I have some difficulties to imagine why the Arctic ice cap shrinking has caused any harm in the millions of people living around me ... didn't we talk about the disappearance of 99 % of the human population ? do you mean that 99% will commit suicide because of polar bears or what ? Why not throw another biscuit in your direction? 1. Light reflecting Arctic ice cap is shrinking and thinning, exposing heat absorbing water. 2. More heat generated by albedo flip = greater water evaporation intensifying amount of rain and strength of storms which are fueled by the extra heat. 3. Crop and infrastructure damage throughout the Northern Hemisphere due to intense rains and changes in weather patterns. 4. This Arctic Sea exposure thus adding to the already present intensiication in rain and snow due to the temperature increase of other oceans. 5. Temperature increase in an ice free summer Arctic Sea leading to (More deja vu) increase in regional warmth. 6. Which includes Siberia, whose permafrost is melting and releasing Methane (You do know that Methane is a Greehouse gas-don't you?). 7. The increase in Siberia's heat thus amplifies the permafrost melt and methanogen microbial metabolism leading to an escalation in the rate of increase in the release of Methane. I think that's called a positive feedback loop. You may now brush off all of the above. "Compare the Pliocene's arid ecology in North America and please tell me; do you want a bumper crop of corn in Kansas or would you prefer a bumper crop of cactus?" My issue that it was not relevant to equate = level of CO2 = climate, several millions years ago, so why should I answer an irrelevant question ? Yawn! Feeding time over.
       Moderator Response: [Dikran Marsupial] Please can we moderate the tone back to "impersonal scientific discussion" (I know there is an element of "pot meet kettle" there, for which I apologise).
88187. Gilles at 18:49 PM on 17 April 2011
       It's not bad
       so as it is the right place, I post here my question : since the average population, GDP, improvement of standard of living, etc... growth has been positively correlated to temperature up to now, it must be that some other factor (whatever it is) must have been stronger, so that all drawbacks have been offset in a way or another. My question is simple : does our knowledge allow to make a definite prediction of when the correlation will be the opposite ?
88188. Gilles at 17:18 PM on 17 April 2011
       What was it like the last time CO2 levels were this high?
       44 : Marcus : please substantiate your personal attacks, at least. I never stated that population could grow only through FF, and if you say the opposite, show me where. Now YOU said "China has had a much bigger growth rate than the Western Hemisphere-dating back to the middle ages." And I asked you : "what was the average growth rate of China between, say , 1000 and 1800, following you ?" can you at least answer that ? "As someone who works in the Agricultural Science sector, I can assure you that ongoing temperature rises *will* continue to have an ongoing negative impact on crop outputs." And as someone who works in the Agricultural Science sector, are you stating that the price and the availability of FF has no influence on the crop outputs and the price of food ? The problem we're facing now is just demographic expansion - actually we've escaped Malthus' dire prediction for some centuries thanks to the discovery of new territories and the use of FF (yes), but we meet the problem again - and it was unescapable because exponential growth meets always a limit. That's all, and that's enough - warming has nothing to do with that, it can make the problem worse at some places, but it is very far from being the main problem. The main problem is simply overpopulation, and even if we suppressed totally FF, we'd have to face it anyway. Do not mix up the issues.
       Moderator Response: [muoncounter] This is not a thread about historic population growth. Further off-topic diversions will be deleted.
88189. Marcus at 17:04 PM on 17 April 2011
       What was it like the last time CO2 levels were this high?
       "But I did never stated that population could only grow thanks to FF" Yes you have, on more than one occasion-you only ever claim that's not the case when people finally blow your claims clear out of the water. The graph you provide doesn't exactly help your case-given that the population growth really got going during the 16th century & onwards. Also, I never said China's growth rate was huge in the middle ages-just signficantly larger than that of Europe during the same period. China's population growth rate post 1970's *is* lower than what it was previously-I can't help the fact that you refuse to accept that fact. My other points, which you can't even be bothered to address, merely highlight how weak your entire case is. "what I stated that I saw no sign, nowhere, that a growing temperature produced a decrease in the population" As someone who works in the Agricultural Science sector, I can assure you that ongoing temperature rises *will* continue to have an ongoing negative impact on crop outputs. Technological fixes can alleviate this to some degree, but only at a much increased price for staple goods. Now if you think a world of increased crop failures & more expensive foodstuffs is good for a world which is already failing to feed its entire population, then you're simply much, much more deluded than I ever thought.
88190. Gilles at 16:48 PM on 17 April 2011
       How I lived through a carbon tax and survived to tell the tale
       " I never said ... that there is a significant risk that we can't switch away from FF." You never said there is, or you never said there isn't ?
88191. Gilles at 16:40 PM on 17 April 2011
       What was it like the last time CO2 levels were this high?
       I'm sorry for english, "meanwhile" wasn't the appropriate word :) so why did the world cool after Pliocene ? Now i'm rather stupefied by the number of false and unsubstantiated statements I can read in your answers - it's unfortunately a little bit lengthy to answer all, so please forgive me if I forget some. "the obvious prospect of severely escalating problems in the future." : well obvious if you believe in them, and if you're formatted by the impressive number of dire predictions that are made everywhere - but actually there is no "obvious" fact about an imminent catastrophe. recent example drawn from a competitor site http://asiancorrespondent.com/52189/what-happened-to-the-climate-refugees/ maybe we'll soon have here a post on this subject ? "You are concentrating on a natural event that is sporadic in a given time period versus human distorted 'natural' events which are increasing on a year by year level." ... which human distorted natural events are increasing on a year to year level ? well , they're probably "human distorted" but not quite in the same sense ... "Besides, you have not responded to the issue of Arctic Ice cap shrink and its effects in the near future. " I have some difficulties to imagine why the Arctic ice cap shrinking has caused any harm in the millions of people living around me ... didn't we talk about the disappearance of 99 % of the human population ? do you mean that 99% will commit suicide because of polar bears or what ? "Compare the Pliocene's arid ecology in North America and please tell me; do you want a bumper crop of corn in Kansas or would you prefer a bumper crop of cactus?" My issue that it was not relevant to equate = level of CO2 = climate, several millions years ago, so why should I answer an irrelevant question ? Marcus " you only care that the world consumes more of your precious fossil fuels," As my point is precisely that it won't , I have some difficulties to understand why you say that. " China has had a much bigger growth rate than the Western Hemisphere-dating back to the middle ages." Really ? what was the average growth rate of China between, say , 1000 and 1800, following you ? Hint : the average growth rate of A(t) in the [t0,t1] interval is ln[A(t1)/A(t0)]/(t1-t0). "ts also funny that China's growth rate, over the last 30 years, has been less than any time during at least the last 500 years-" do you realize what an exponential growth really means ? the current rate is around 1%, giving a doubling time of 70 years. 500 years of 1% growth rate makes 2^(500/70) = 141 , so now we learn that China had less than 10 millions inhabitants in 1500 ? actually here is the real growth of population (http://afe.easia.columbia.edu/special/china_1950_population.htm) very far from your figures ) and nearly flat during the Middle Age. The growth started just before the industrial revolution, indeed, but it is remarkable that it exhibits some "hockey stick" shape correlated .. positively with temperature ! But I did never stated that population could only grow thanks to FF, although I think they're quite a part of it (it is not necessary to have much FF - it's enough to avoid famines through agricultural productivity): what I stated that I saw no sign, nowhere, that a growing temperature produced a decrease in the population. Can you stick on this assertion ?
88192. RSVP at 16:34 PM on 17 April 2011
       Waste heat vs greenhouse warming
       Not sure if anyone has used this analogy yet. Global warming as obesity. When a person is overweight, there are usually many causes, but they all reduce to the net ratio of calorie intake over calories burned greater than unity. And while this idea is fairly simple, it's not always clear why doing all the right things doesnt result in a desired weight loss. For one thing, there are time delays associated with metabolic processes that introduce lag. Things take time. In the same way, to say that radiative heat will simply increase to offset the effects of waste heat is not recognizing inherent lag. You cant just fixate on the SB formula and think it is going to solve all your problems. Picture a nuclear power plant next to a river. If I were to accept the arguments being proposed here against waste heat, I would have to believe that as soon as the water comes out of the plant it will cooled to the same temperature above the plant. Everyone knows this is not the case. So I would ask how far downstream must one go for the heat to magically disappear, making me "horribly, horribly" wrong?
88193. Marcus at 15:53 PM on 17 April 2011
       David Evans' Understanding of the Climate Goes Cold
       Nick, what you've also got to remember is that if we manage to cut global CO2 emissions back to 1990 levels, then there's also the possibility that new & existing carbon sinks might be able to take up some of the excess CO2 already in the atmosphere. This will be even more likely, of course, if we can cut our CO2 emissions back to pre-1950 levels. Maybe I'm being overly optimistic, but one can always hope.
88194. BillyJoe at 15:52 PM on 17 April 2011
       Muller Misinformation #3: Al Gore and polar bears
       Taking legal action to silence the misinformation supplied by climate denialists would be seen as a conspiratorial attempt to silence the whistle-blower.
88195. Marcus at 15:38 PM on 17 April 2011
       What was it like the last time CO2 levels were this high?
       Wow Gilles, you're an even bigger piece of work than I thought you were-& that's really saying something. Here you've been, telling us over scores of postings, how you believe consumption of fossil fuels is necessary to save the lives of people in the developing world-yet clearly you don't give two hoots about human life, you only care that the world consumes more of your precious fossil fuels, & damn the consequences. Also, like any good denialist, you believe that repeating the same myths will somehow make them true-like your false FF consumption correlates with population growth meme. Well guess what? It was wrong before, & its still wrong now. China has had a much bigger growth rate than the Western Hemisphere-dating back to the middle ages. Was that because they had coal-fired power stations the European World wasn't aware of? No, its because they had much better medicine, education & sanitation than the Europeans. Its also funny that China's growth rate, over the last 30 years, has been less than any time during at least the last 500 years-yet their fossil fuel consumption in the last 30 years has been at its highest during that same time-frame. Kind of knocks your ill-founded "correlation" fantasy on the head, doesn't it? Similarly, population growth rates in the West actually started to climb significantly around the end of the 18th/start of the 19th century. Again, improvements in health care, sanitation & income distribution seem to be the most likely causes. Also, according to what I've seen, yearly growth rates have fallen from around 2% per year in 1970 down to around 1.2% per year in 2010-not exactly great evidence for your "correlation" myth, is it Gilles? Last of all, in recent history some of the biggest population growths have occurred in Countries like Thailand, The Philippines, Brazil & Mexico-in spite of the fact that their fossil fuel consumption remain far lower than those of the less populous, so-called "advanced" economies of Western Europe & North America. Again, not great "evidence" for your "correlation" myth. It seems you understand historical correlations about as well as you understand the drivers of climate change & release & take-up of greenhouse gases. That is to say-you don't understand them *at all*, & should probably go & educate yourself before you embarrass yourself even further.
       Moderator Response: [DB] Your spirit is appreciated, but your energy is better served someplace where productive results are achievable. Unfortunately, this is not one of those. DNFTT.
88196. RSVP at 15:36 PM on 17 April 2011
       Waste heat vs greenhouse warming
       and what import does the radiation between molecules have if all they do is exchange energy between themselves? Here we have 100% cancellation of anything remotely resembling a cooling mechanism, as the only thing that matters is the net vector from the surface skyward.
88197. RW1 at 15:12 PM on 17 April 2011
       Clouds provide negative feedback
       Dessler 2010 seems to be claiming that clouds are trapping more energy as the surface warms. He writes on page 3 of his paper: "Because I have defined downward flux as positive, the positive slope here means that, as the surface warms, clouds trap additional energy; in other words, the cloud feedback here is positive." Is he claiming that clouds are changing in a way that results in them trapping more surface energy? If yes, how has he rectified this with all the data (i.e. how has he shown that the additional energy the clouds trap is greater than the additional energy they reflect away)???
       Moderator Response: [Muoncounter] There is an existing thread for Dessler's paper; check to see if your question was already addressed.
88198. Tom Curtis at 15:06 PM on 17 April 2011
       A Flanner in the Works for Snow and Ice
       Ken Lambert @68, in reviewing my calculations I noticed I did not adjust the atmospheric absorption for my error regarding angles in 54. Rather than pursue that line of calculations, I have recalculated the increase in incoming energy over the arctic summer due to the change in ice area between the early 1980's and the late 2010's. I have proceeded as follows: 1) For each half hour of the 21/5/2011, I calculated the minimum solar altituded at 75 degrees North and 0 degrees East using azimuth and altitude calculator to which you have previously linked. I then compared those values to a selection of values calculated for 20/7/2011 to ensure those of 21/5/2011 are smaller (they are). As previously discussed, these dates are chosen because they lie thirty days on either side of the summer solstice. Thus, for sixty days of the summer, the altitude will be higher than these values, and for the remaining 30 days, not much lower. Taking these values, therefore, represents a conservative estimate of the mean summer values. Having determined the minimum altitude for each half hour, I then rounded down to the nearest whole degree. 2) For each half hour, and using the result of (1), I then calculated the albedo of sea water for water incident at that angle using the Fresnel equations, the effective path length through the atmosphere as a multiple of the height of the atmosphere, and the effective surface area over which light striking one meter squared perpendicular to the light would spread on the surface (in square meters). The later two are calculated using the formula =1/(SIN(RADIANS(D55))), where the radians function converts degrees to radians, and the sin function gives the sine of an angle expressed in radians. 3) Using values for cloud albedo and atmospheric absorption taken from Trenberth's chart (in 54 above), I then calculated incident radiation at the surface in watts/m^2 for each half hour of the day using the formula: I = S * (1-C) * (1-(L*A)/area where I equals the incident radiance, S equals the TSI, C equals the cloud albedo, L equals the path length of the light where the height of the atmosphere = 1, A equals the mean atmospheric absorption , and area equals the area over which light that passes through one square meter perpendicular to the light path at the top of the atmosphere will pass. Where this formula returned a negative value, I used 0. To ensure the value was conservative, I used the TSI at aphelion, which is 1321 W/m^2 {{=IF((($D$52*(1-$G$52)*((1-($I$52*F55))/G55)))<0;0;(($D$52*(1-$G$52)*((1-($I$52*F55))/G55))))}} 3a)As a check against whether this constitutes a conservative estimate, I calculated the mean incident radiation over a day using the above method, which was 127 w/m^2. For comparison the following map shows the annual average surface solar energy including the effects of clouds and atmospheric absorption: As you can see, the average over the whole year including six months of darkness, is nearly 100 w/m^2, so my estimate for the summer months of 127 W/m^2 is certainly conservative. 4) From the half hourly values obtained in (3), I calculated the additional energy absorbed by ocean surface exposed by melting sea ice as the difference between the albedo (0.9) of the sea ice and the albedo of the ocean given the angle of incidence, multiplied by the effective surface radiation (as calculated in 3). Taking the mean of that value, the average additional power absorbed by the ocean is 97 W/m^2. 5) Using that value, I calculate the total additional energy absorbed as 7.57 x 10^8 Joules per meter squared over a notional 90 day summer, or 1.51 x 10^21 Joules over the whole 2 million square km of additional ice cap melted over the period 1979-2011. This is a reduction from my 1.7*10^21 estimate in 56, but is now (at last) error free so far as I can determine, and still a very conservative estimate. So conservative, in fact, that it assumes zero insolation for 9.5 hours of the day in the arctic summer. But it is still a sufficiently large figure to show that you are significantly underestimating the forcing effect of arctic melt back, and that there is no basis from considerations of incoming energy to think Flanner is incorrect about overall forcing.
88199. RW1 at 14:19 PM on 17 April 2011
       Clouds provide negative feedback
       Sorry, but I'm not interested in a semantics debate regarding the definition 'skeptic'. ['...the system's response to GHG forcing will be much greater than it is to solar forcing...'] "This is untrue. You are the only person on the planet to have arrived at this conclusion, because your underlying model (understanding) is flawed." I don't see how this is untrue. I make no claim that it's an impossibility, but it is true that the AGW theory claims the next 3.7 W/m^2 incident on the surface will be amplified by the system nearly 3 times a much as the original 239 W/m^2 incident on the surface from the Sun. If, as the AGW theory claims, an additional 3.7 W/m^2 at the surface is to become 16.6 W/m^2 mostly through positive feedback, quantify specifically how the feedback causes this much change while it doesn't for the original 98+% (239 W/m^2) from the Sun. "But that model -- the rules and assumptions you are following -- are flawed." Explain why.
88200. Bob Lacatena at 13:37 PM on 17 April 2011
       Clouds provide negative feedback
       12, RW1,

       I don't have a model.

       Of course you do. Everything in science is a model. You have a mathematical model (a set of rules and assumptions) that you've used to derive your proposed answer from the data. But that model -- the rules and assumptions you are following -- are flawed.

       ...the system's response to GHG forcing will be much greater than it is to solar forcing...

       This is untrue. You are the only person on the planet to have arrived at this conclusion, because your underlying model (understanding) is flawed.

       ...my purpose here is to present contradictory evidence and logic that disputes the theory. That's what I'm doing.

       No, what you're doing is confusing people with your own personal creation of faux-math-science.

       I have not seen, in my estimation, these relatively simplistic things explained by the pro-AGW advocates.

       No one can explain to you why 2 plus A does not equal monkeys, because it's not even a mathematical equation. Similarly, your insistence that some theory must explain your 1075 W/m² number will never happen.

       I'm a staunch skeptic of AGW

       That's an oxymoron. No one can be a "staunch" skeptic. Being skeptical means questioning what you are first shown until it is satisfactorily proven, not questioning it endlessly with no hope of acceptance or understanding, because you staunchly refuse to be anything but eternally skeptical.
       Moderator Response: [Muoncounter] We've been down this painful road before. Please do not encourage another go round. The other player in the drama is known as co2isnotevil, which should tell you all you need to know about his viewpoint.

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