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malamuddy at 14:03 PM on 19 February 2011Monckton Myth #13: The Magical IPCC
I know this is slightly OT, but if you would like an excellent discussion of Monckton's Myths (with more to come), go right now to Potholer54 on Youtube (also currently available on Crock of the Week). The guy who prepares these little gems (Peter Hatfield) is a retired(?) journalist who was a regular correspondent for New Scientist. His material deserves a much wider audience. -
Rob Honeycutt at 14:02 PM on 19 February 2011Meet The Denominator
Poptech... "Whether a paper was peer-reviewed is not subjective..." The issue is less about whether the papers are peer reviewed and more about whether they challenge AGW. The question of peer review comes from your extensive use of E&E which most working scientists consider to be the backwater of science. Kind of the last place you go when you can't get your paper published. "I have no intentions of publishing a paper on the list. " Where is that confidence you exude? Does it disappear when you believe that people will actually put your list under scrutiny? "If you were giving me the benefit of the doubt then you would not have linked to Greenfyre's nonsense" It's perfectly reasonable to point people to the challenges to you work, whether you agree with them or not. "But I am not just here for your comments but also to correct those from other posters." You realize, though, the more you post the more people respond. Right? -
RW1 at 13:53 PM on 19 February 2011A Swift Kick in the Ice
Rob Honeycutt, What percentage of the average global albedo is the Artic? -
kiwichick at 13:52 PM on 19 February 2011A Swift Kick in the Ice
hi guys, first post http://climateprogress.org/2011/02/17/nsidc-thawing-permafrost-will-turn-from-carbon-sink-to-source-in mid-2020s-releasing-100-billion-tons-of-carbon-by-2100/Moderator Response: Welcome! In future please provide context for links, or your comment will be deleted. For this one, please post an additional comment with context such as a question. -
Tom Curtis at 13:38 PM on 19 February 2011A Swift Kick in the Ice
@17 HGP: 1) Grapes are not a tropical fruit, they are a temperate climate fruit. They were grown as far north as Yorkshire in the Medieval Warm Period, and in Southern England in roman times, but never in Scotland. They are now grown in Yorkshire once more, and indeed are now grown in Sweden commercially outside of greenhouses, which has never happened before. One essential difference between now and the past is the relative cost of transport. High costs of transport during Roman and medieval times made it sensible to grow grapes to the limit of their cultivation. That is why grape growing survived in Southern England right through the LIA, but died early in the 20th century. However, even though transport is now cheap, growing grapes is sufficiently easy to make local commercial grape growing even in Yorkshire. 2) During the summer months, the Earth receives more energy from the sun at the poles than at the equator. This is because the poles have 24 hour sunlight, even though the sunlight is much weaker because of the high latitude. The essential difference between ice and water in this context is that ice reflects approximately 90% of incoming sunlight, while water absorbs approximately 90% of incoming sunlight. In the summer months, that vast change in albedo, which coupled with the high summer insolation will make a significant change to overall global temperatures. That is quite apart from any ecological concerns about several species of seal and fish which are entirely dependent on sea ice for birthing (seals) or food (fish), or an even larger number of species including polar bears that are primarily dependent on sea ice. 3) Sea levels are currently rising faster than is predicted by the models. This does not make sea levels a matter of significant concern for the next 50 odd years, but after that sea levels will have risen high enough to impose significant adaption costs. You obviously draw your information primarily from denier sites (either directly or indirectly). You should avoid that. They lie to you. They lie frequently, and with breath taking bravado. It is impossible to form a rational opinion based on deliberate falsehoods, so if you want to learn about global warming, avoid denier sites like the plague. At the very least, never believe anything you read on one of those sites until you have confirmed it on at least to genuine science sites like Skeptical Science and Real Climate. -
Tom Curtis at 13:21 PM on 19 February 2011A Swift Kick in the Ice
HR @16: 1) There may have been ice free summers in the Holocene Climactic Optimum, but there certainly have been none since then. In view of the very large difference in Milankovitch forcing between now and then, that is no reason to suppose the current decline in arctic summer sea ice is natural. 2) Arctic sea ice will melt for any warming, but warmings due to increased insolation or reduced cloud cover will have a strongest primary effect at the tropics. The net effect should be that the primary warming at the tropics and the secondary warming in the arctic should be of similar magnitude. In contrast, warming due to a strengthened greenhouse effect has a stronger effect at high latitudes than at the equator, which are then reinforced by the arctic amplification, resulting in much higher arctic warming than that seen in the tropics. It is the later we in fact observe, not the former. Changes due to orbital mechanics have a different pattern, with net incoming energy remaining essentially unchanged, but with large variations of insolation at high latitudes. Consequently polar amplification can reinforce an effect which preferentially warms NH summers. However, we know from astronomical observation that we are currently approaching a minimum in NH summer insolation. Hence, if that were the only influence, we would expect the arctic amplification to be increasing a reduction in summer temperatures, not an increase. Pretending that because High summer insolation coupled with polar amplification has lead to an ice free arctic summers in the past, that therefore our rapid approach to ice free arctic when we have low summer insolation is because of natural causes is disenginuous at best. -
HuggyPopsBear at 13:05 PM on 19 February 2011A Swift Kick in the Ice
I am seriously trying to follow you guys without physics a subject I always wanted to learn but could not grasp, I am left with basic logic and observation. Can someone please explain the importance of why losing ice is and seems (to me) to be a bit of scaremongering. From what I can see and knowledge of history, like everything else on this planet it goes in cycles. One minute we are hot another cold. One minute theres ice and the next there is not. I can remember as a child rivers (salt) freezing over in southern England that you could walk on. We also know that the arctic regions were once fertile and that Mammoths were frozen in situ as they grazed these areas. In Roman times grapes tropically grown fruit was being farmed in Scotland and CO2 level were supposedly higher then than now as well as temperatures higher than now. Also why are sea levels not rising as high and as fast as some models predict with the big melt? Now I have tried to find out how true this is but supposedly oil companies as they pump the oil out of the ground is floated up by injecting sea water. If true how many millions of gallons of sea water is used, which is lost forever if the case is provable? -
HumanityRules at 12:41 PM on 19 February 2011A Swift Kick in the Ice
Rob, "If the Arctic Sea is covered with ice in the summer - as it has been dating back perhaps thousands, to millions of years - the incoming sunlight is mostly reflected back to space without adding any heat to the Earth. But, as ice melts back, as is happening today, the summer sun is absorbed by the darker open sea exposed by the disappearing ice." This couplet of sentances seems to allow for mis-interpretation. The wording seems to suggest that todays conditions represent a departure from conditions that have persisted for thousands or millions of years. This of course is not true. Evidence exists for possible ice free summers on thousands of years time scale. 11 Tom Curtis Just for completedness, amplification isn't a feature specific to the greenhouse effect. It occurs in the history of the arctic during warming phases attributed to other forcings. For general interest there are two extensive science reviews here and here from a long list of eminent authors. My guess this would be the concensus view heading for AR5. -
Chemware at 12:30 PM on 19 February 2011A Swift Kick in the Ice
... and very few people realise an important fact about Antarctica: it has an avergage elevation of 2,286 m. As a consequence, it is naturally colder than the Arctic, by about 20°C (calculated from the lapse rate), and so most Antarctic ice will be very slow to melt to a significant extent. Glaciers sliding into the ocean faster because of melting near the coast is another matter. -
Tom Dayton at 12:21 PM on 19 February 2011Models are unreliable
Jue1234, see in the RealClimate post "FAQ on Climate Models," the "Questions" section, "What is the difference between a physics-based model and a statistical model?", "Are climate models just a fit to the trend in global temperature data?", and "What is tuning?" A relevant quote from those: "Thus statistical fits to the observed data are included in the climate model formulation, but these are only used for process-level parameterisations, not for trends in time." Part II of that post then provides more details on parameterizations, including specifics on clouds. -
Tom Curtis at 12:02 PM on 19 February 2011A Swift Kick in the Ice
Albatross, there was a model in sight. It was just simple enough to be implemented by pen and paper. This is one of the biggest confusions about models, which are in fact just mathematical equations which are worked through to find out what they actually predict. As some deniers rightly claim, models are not evidence. But they are the predictions of physical theory. As it happens, no plausible physical theory using only natural forcings predicts the warming in the late 20th century, nor the greater warming in the arctic, nor the decrease in the difference between day and night temperatures, nor the cooling stratosphere combined with a warming troposphere. All plausible physical theories including natural and anthropogenic forcings predict these. In this circumstance, rational people prefer the theories that actually predict what is actually happening. Deniers just obfusticate. -
nigelj at 11:57 AM on 19 February 2011The Dai After Tomorrow
I like this site. I have read these posts hoping to see if there is valid evidence to support an incresing frequency of droughts. Instead some character called Berenyi Peter highjacks the entire thread, trying to nitpick an article title that is simply in effect a summary and suffers what all summaries inevitably do it generalises, because its a summary or title! He then waffles on about preparing for natual disasters, well off topic, gives me a headache with his constant itallics, and make claims about cost mitigation and precautionary principles without a shred of proof, but plenty of straw man arguments. I give up I cant be bothered Im off elswhere..Moderator Response: [DB] As Marcus points out immediately below, thread hijacking, as attempted by BP on this thread, will not be allowed to succeed. Debate and even disagreement is encouraged, as long as they comply with the Comments Policy. If needed, more extreme methods exist to deal with repeated violations of the Comments Policy. For a more in-depth discussion of the science of droughts in a warming world, I encourage you, and everyone, to read the paper which is the subject of this blog post. Bring any questions about it here and someone will attempt to answer them for you. Thanks for caring enough to make a comment of your own. -
Rob Honeycutt at 11:45 AM on 19 February 2011Meet The Denominator
"I am here in this post to correct misinformation about the list." Interesting because the whole premise of the article was not to challenge the list at all. I said repeatedly that I was giving you the benefit of the doubt. I merely was attempting to put the number into a broader context relative to the full body of science on climate change. -
Models are unreliable
Jue1234 - You might find the Hansen's 1988 prediction page a useful answer. His predictions are holding fairly well through now. His initial climate sensitivity number was a bit too high - but adjusting for the better sensitivity estimates and actual emissions shows the model (simple as it was) still holds up. Models are not just based on hindcasting - that's a required check, but the assumptions going into the models are based on physics, not just mathematical modeling of previous behavior. -
Albatross at 11:36 AM on 19 February 2011A Swift Kick in the Ice
Tom @12, But Tom, the models, those hopeless models!! I jest, that was a very interesting post, and not a model in sight, probably not even in his wildest imagination...just hard physics. Very cool. And despite what Lindzen thinks, as shown by Ari's recent post on ocean levels (which I highly recommend) and the two recent seminal nature papers on extreme events, models can be incredibly useful tools. -
Rob Honeycutt at 11:34 AM on 19 February 2011Meet The Denominator
"Can a moderator explain why this post was deleted as I do not understand what policy was violated" Don't worry Pop. I've had a number of posts deleted as well. -
Rob Honeycutt at 11:32 AM on 19 February 2011Meet The Denominator
Poptech.... You have such incredible confidence in your list, why not validate it by writing up a paper and getting it published? If a top journal published your paper then you would shut all of us up forever and validate all of your points. And no, we won't shut up if it gets published in E&E. A top journal. Nature or Science or equivalent. Anything less and you're just blowing smoke. -
Tom Curtis at 11:31 AM on 19 February 2011A Swift Kick in the Ice
David Horton @9, I strongly suspect that what you say is true about the hard core deniers. What will change when yachts can regularly sail to the north pole in summer is that the hard core deniers will no longer have any credence with the general public. They will be viewed, and rightly so, with the same mental condescension that is reserved for flat earthers and geocentrists. -
Tom Curtis at 11:28 AM on 19 February 2011A Swift Kick in the Ice
An excellent article, and very clear. It may be of interest that Arrhenius first calculated the increased warming at higher latitudes in 1898. He wrote: "... I have calculated the mean alteration of temperature that would follow if the quantity of carbonic acid [CO2] varied from its present mean value (K=1) to another, viz. to K=0.67, 1.5, 2, 2.5, and 3 respectively. This calculation is made for every 10th parallel and seperately for the four seasons of the year. The variation is given in Table VII. A glance at this Table shows that the influence is nearly the same over the whole Earth. The influence has a minimum at the equator and rises to a flat maximum that lies further from the equator the higher the quantity of carbonic acid in the air. For K=0.67, the maximum effect lies about the 40th parallel, for K=1.5 on the 50th, for K=2 on the 60th, and for higher values above the 70th parallel. The influence is generally greater in winter than in summer, except in the part that lies between the maximum and the pole. The influence will also be greater the higher the value of [absorptivity], that is in general somewhat greater for land than for ocean. On account of the nebulosity [cloudiness] of the Southern hemisphere, the effect will be less than in the Northern hemisphere. An increase in the quantity of carbonic acid will of course diminish the diference in temperature between day and night. A very important secondary elevation of the effect will be produced in those areas that alter their albedo by the extension and regression of snow-covering, and this secondary effect will probably remove the maximum from lower parallels to the poles." So, the current polar amplification was predicted over 110 years ago on the presumption of the greenhouse effect, while it so confounds denialist theories that they have to assert, against the evidence, that it is not hapening. Arrhenius' prediction was made without considering the effects of changes in water vapour levels due to change in temperature. I do not think that those changes suggest a stronger heating at the equator. It is true that the greatest greenhouse effect due to water vapour is found in the very humid tropics, but the change in humidity is due to the change in temperature, and that is not automatically stronger at the equator. In fact, the change in temperature is weakest at the equator, though because of the high temperatures, the change in humidity may be slightly higher there. -
Jue1234 at 11:27 AM on 19 February 2011Models are unreliable
This may be a naïve criticism- but how do you avoid the problem of circularity in using hind-casting to establish the accuracy of climate models? The assumptions for the models can only be based on observations of what has happened in the past, so to create a model based on these assumptions means that it is inevitable that it will accurately predict what has happened in the past. The more established patterns are encoded into the model, the more accurately it will predict the past. It would be ironic if some of the most powerful computers in the world were generating tautologies. This is not a problem for climate science alone. It is a problem for any time-based models. I have been involved in environmental predictions based on using multivariate regression analysis of GIS data correlated with soil types. This falls into the same problem, but it can be amended by later sampling of soils at predicted locations, and correlating the observed soil type with the predicted soil type and running a t-test to establish the reliability of the prediction. It would be useless to sample the same site that the model was based on. The only way that the same calibration could be carried out in time-based climate models is by comparing forecasts with what happens in the future and not the past. Are the models therefore proper science. Without reference to the future they are unfalsifiable. The absence of controls is another issue. I understand the practical problem of testing the accuracy of long-term models in this way. The damage may have been done before the data is in. Can you post a link to papers which articulate the assumptions behind these models? -
muoncounter at 11:26 AM on 19 February 2011It's not bad
First comes snow, then comes the floods of snowmelt. But this year may be worse due to the already saturated ground. NOAA Hydrologic Center: North Central U.S. Spring Flood Risk Heavy late summer and autumn precipitation (twice the normal amount since October in parts of North Dakota and Minnesota) have soils saturated and streams running high before the winter freeze-up. Another winter of above average snowfall has added water to the snow pack on top of the frozen saturated soils in the North Central US. NWS models show this snowpack containing a water content ranked in the 90 to 100 percentile when compared to a 60 year average. These factors have combined to create some of the highest soil moisture contents of the last century. NWS one-month climate forecasts show chances favor a colder than normal last month of winter across the entire North Central U.S., while precipitation patterns appear to be near normal. -
Albatross at 11:13 AM on 19 February 2011Deep ocean warming solves the sea level puzzle
Fantastic post Ari and very interesting! This answer is a little surprising, and somewhat distressing too. -
Rob Honeycutt at 10:36 AM on 19 February 2011A Swift Kick in the Ice
David... There are many for which I think what you say is exactly true. But I also think there are different extremes of denial. Ice is a pretty clear, visible signal. It's there or it's not. There's no quibbling about degree or missing heat or other issues. Ice has this way of drawing a line in the sand (or sea). As more and more ice disappears incrementally more and more people are going to sit up and take notice. The ice is going away, that's clear. With thermal inertia we have several more decades of warming no matter what. Arctic summer ice is going to be gone before that. Hopefully the far extreme deniers will become more and more marginalized during the process. -
CO2 limits will harm the economy
Berényi - As an example of climate change costs: the Central Valley (around Sacramento) in California, USA, is a major 'bread-basket' region, producing 8% of the USA agricultural output. That agriculture is fed by year-round Sierra mountain snowcap runoff, which is shrinking due to global warming and reduced snow accumulation. Rice crops will be among the first to suffer, but all agriculture needs water - 20-50% less over the next century. Walnuts, cherries, prunes and peaches, on the other hand, require lower winter temperatures to produce, and are declining as well; by 2100 about half the $9B annual fruit and nut crop will not be able to survive there. Minimizing these sorts of changes is the economically wise thing to do; I fail to see how you think otherwise. -
David Horton at 10:11 AM on 19 February 2011A Swift Kick in the Ice
"fairly certain that all of it will need to be gone before they say "maybe."" - dunno Rob, I think you will find that when it is all gone they will be more firmly insisting that the Chinese sailed over the north pole in 1423, and that of course there wasn't any ice there 100 million (choose figure at random) years ago, and that polar bears have only just evolved. I have long concluded that there is absolutely no point at which the deniers will recognise the error of their ways. No point at all. Every step along the road to the year 2100, every shift in climate, every catastrophic event, every species extinction, every loss of coral reefs, will be explained away, rationalised, dismissed as having been seen some time on the past, or as too expensive to fix (except, if you insist, by a combination of nuclear power and DDT). -
Rob Honeycutt at 09:59 AM on 19 February 2011A Swift Kick in the Ice
Badgersouth... You know, I find the ice issue really interesting exactly for that reason. It's quite clear that the planet is losing ice at an accelerated rate by any number of measurements. But it's an issue that climate deniers tenaciously hang on to for dear life. Many of the arguments are listed here on SkS, of course. But when I'm on other sites arguing I'm amazed at how they hang on to these ideas. These people are utterly convinced that the ice is now starting to come back. They're as sure as they are that the sun will come up tomorrow. I'm really curious how much summer ice needs to disappear before finally acknowledge that it's disappearing. I fairly certain that all of it will need to be gone before they say "maybe." It's like a parallel reality. I like to point out that, after 2007, Arctic sea ice only "rebounded" to the accelerating declining trend. I suggest that, maybe if we were seeing a few years popping up past the 2 standard deviation trend on the positive side... then they might have something. But such comments seem to go unnoticed. -
CO2 limits will harm the economy
Berényi - I looked at a number of the analyses. Cost estimates per US household were estimated at $80-160/year, or ~$20-50/person/year, not too much, with lower prices for lower income families. Economic benefits include deficit reduction, $$ for investment in renewables/energy efficiency/lower polluting tech, and a reduction in greenhouse gas accumulation, hence a reduction in warming speed and mitigation of global warming consequences and their associated costs. And that's completely without considering the "Other Side of the Coin" paper, which uses a range of societal carbon costs estimates established by fairly detailed Department of Energy estimates. If you don't like that paper, take the estimates and do the calculations yourself. Sounds like an good economic trade to me. Avoiding some of those considerable upcoming costs is income, if you can look at and plan for the future - rather than being short-sighted about immediate rewards. -
Berényi Péter at 09:29 AM on 19 February 2011The Dai After Tomorrow
#24 David Horton at 08:48 AM on 19 February, 2011 as you are suggesting, we don't have to worry about CO2 levels increasing because plant growth will increase and therefore all the extra CO2 will be removed from the air - how did we get such extreme climate change in the past? Am I suggesting such a thing? I don't think so. Where have you read it? As for extreme climate changes of the past like glacial-interglacial transitions, they were not caused by CO2. The science is settled, there is robust consensus over this particular issue.Moderator Response: [DB] BP, that is certainly the interpretation any objective reader would have to draw based on your comment at #20 above. Please continue your disinformation campaign elsewhere. -
pbjamm at 09:23 AM on 19 February 2011Empirical evidence for positive feedback
co2isnotevil@78 Please provide some evidence to back up your assertions. Being dismissive and condescending does not add anything constructive to the discussion. -
RickG at 08:55 AM on 19 February 2011The Dai After Tomorrow
#20 BP, Are you familiar with the Keeling Curve? Not just that it shows annual increasing of atmospheric CO2, but the peaks and valleys of the annual curve?
The valleys occur in the summer when vegetation is taking in CO2. The peaks occur in winter when the decaying vegetation is releasing the CO2 they previously took in. The reason the curve is rising overall is due to the anthropogenic contribution. Yes CO2 is plant food, but plants also release that CO2 it in the winter. Plants can only take up so much CO2.
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David Horton at 08:48 AM on 19 February 2011The Dai After Tomorrow
Berenyi I know this is a futile question to someone not wanting to worry about global warming because a volcano might erupt some time, but if, as you are suggesting, we don't have to worry about CO2 levels increasing because plant growth will increase and therefore all the extra CO2 will be removed from the air - how did we get such extreme climate change in the past? -
Berényi Péter at 08:44 AM on 19 February 2011CO2 limits will harm the economy
#6 KR at 06:14 AM on 19 February, 2011 Berényi - Benefits look to outweigh costs by a factor of 2 to 8, neglecting benefits such as decreased air pollution, ocean acidification, and overall climate change. Your cost argument does not hold up. Come on. Have you actually read Policy Brief No. 4 from Institute for Policy Integrity (which is not a peer reviewed paper so I wonder how is it allowed at this site at all)? Anyway, it all depends on discount rate, about which the authors say The interagency review process acknowledged that "[t]he choice of a discount rate, especially over long periods of time, raises highly contested and exceedingly difficult questions of science, economics, philosophy, and law." The benefits Holland & Schwartz are talking about are clearly not economic benefits, as they depend on such things as science, philosophy and law, but never on supply and demand, so they do not constitute a true income. Therefore they are not comparable to costs. End of story. -
muoncounter at 08:44 AM on 19 February 2011The Dai After Tomorrow
BP: "a major volcanic eruption in the Tropics can cause multi-year cooling & drought conditions, hence widespread crop failures. This kind of event can happen any time and we have absolutely no control over its occurrence." Sounds like something a major Alarmist might say. However, while major eruptions are certain to occur over geologic time scales, that's a gross mischaracterization of the probability of a major volcano on a human time scale. Ample work on volcano occurrence probability exists, all the way down to a quantitative assessment of the risk of death by volcanic eruption. For example, from Newhall and Hoblitt 2000, an individual is 5x more likely to die as a result of a hurricane, 20x in flooding and 2500x employed in mining and quarrying than from volcanic eruption. The occurrence of explosive eruptions (those that could potentially produce global scale cooling) is a logarithmic function, decreasing with volcanic explosivity index (VEI): VEI 5 (Mt. St. Helens) is <100 per 1000 years, VEI 6 (Krakatoa-class) is ~10 per 1000 years, VEI 7 (Tambora) 3-4 per 1000 years. A catastrophic Yellowstone event (VEI 8) is <0.05 per 1000 years. So it is remarkable that one can be more concerned with the negative effects of low probability explosive volcanoes than the negative effects of high probability climate change. -
John Hartz at 08:19 AM on 19 February 2011A Swift Kick in the Ice
Does any of what you describe occur in the parallel world of the climate deniers? -
Albatross at 07:29 AM on 19 February 2011The Dai After Tomorrow
BP, Please read the links that I gave you. The "myth" I am referring to is the claim that we essentially do have to worry about drought in the future because higher CO2 is beneficial to "plant life". The images that you posted are also a strawman, a red herring too-- but I am glad that you did, because it demonstrates yet more issues with your argument. But first, I did not contest that C3 plants do not benefit from enhanced CO2, at least under ideal conditions. you made the generalization about all "plant life", the literature suggests otherwise. Now to your pictures. First, we are a long ways off from a CO2 of 700 micromol mol-1 CO2. Second, you do not provide a link for the photos you produced, was it Rogers (1992). If so they say in their abstract "Results from this controlled environment investigation demonstrate....". So where were those plants grown? Were they exposed to elevated temperatures as well? Were they well watered, what about nutrient supply? Again, while there may be some benefits to doubling CO2 for C3 plants, but on the whole these are very likely going to be far outweighed by the cons. Have you looked up permanent wilting point yet? Those extra roots on the RHS image would be no help to a plant should the root-zone soil moisture drop below the permanent wilting point as often occurs during drought. In fact, even when the plant-available water content drops below 30% plants start to experience significant decreases in above -ground biomass growth and photosynthetic activity (e.g., Mitchell et al. 2001). And you know what else plants do not like? Too much water, and note that research has found that extreme precipitation events in many areas are on the increase. But I digress.Moderator Response: This conversation about the specific claim that CO2 will enhance growth, probably at this point should be moved to the thread "CO2 is not a pollutant," where the comments already started addressing that topic quite a while ago. -
Dikran Marsupial at 07:24 AM on 19 February 2011The Dai After Tomorrow
DP@20 CO2 is not the factor limiting growth of all plants in all environments. Yes, in an atmosphere richer in CO2 a soya bean plant grown in experimental conditions with unlimited water may grow larger than a plant grown in a low CO2 atmospher. But that doesn't mean the same is true of plants grown in the natural environment where water is scarce. A better developed root system will only help a plant in drought conditions if water were plentiful enough before the drought for them to grow that large in the first place. So your argument is only valid if additional unstated assumptions are valid, which is unlikely to be univeraslly true. Like many issues in science, it is not a straightforward issue, and simplistic arguments like "CO2 is plantfood" are generally misleading. -
actually thoughtful at 07:23 AM on 19 February 2011Deep ocean warming solves the sea level puzzle
The expansion of the deep ocean should suggest a temperature rise of the deep ocean, and that should relate to the (currently) mysterious Trenberth's travesty of the global heat budget. Can someone with more maths than I confirm or deny (or more likely, shed grey where needed) that this deep ocean expansion does plug that hole in the equation? -
muoncounter at 07:15 AM on 19 February 2011Empirical evidence for positive feedback
co2 "I know that the Sierra alpine glaciers are growing" Odd that there is no empirical scientific evidence to support this anecdotal evidence. In fact, there is quite a bit of evidence to the contrary: See this photo comparison from the Univ. of Portland: Comparisons of the repeat photography reveal that all ten of the glaciers have experienced a reduction in ice volume and surface extent over the past century. See also the 2009 report of the World Glacier Monitoring Service: all records for US glaciers in 2009 show mass loss. Are you perhaps confusing glacial movement with glacial growth? "Look at the work of Spencer, Lindzen and others for more details," I seem to recall that we are still waiting for Spencer's 'magic clouds' to bring negative feedback to the rescue. Dessler and Sherwood 2009 have quite a different view on that feedback. See also Vavrus 2004: Compared with this fixed-cloud experiment, the simulated cloud changes enhance greenhouse warming at all latitudes, accounting for one-third of the global warming signal. This positive feedback is most pronounced in the Arctic, where approximately 40% of the warming is due to cloud changes. The strong cloud feedback in the Arctic is caused not only by local processes but also by cloud changes in lower latitudes, where positive top-of-the-atmosphere cloud radiative forcing anomalies are larger. Any further comments regarding cloud feedbacks, if any are still necessary, should go to the appropriate thread. -
actually thoughtful at 07:14 AM on 19 February 2011A basic overview of melting ice around the globe
I think Peter's comments point out the weakness of human nature when confronted with a multi-decade problem. (And I mean no disparagement of Peter). As a species we are not good at the 30 year+ type planning. Very few (perhaps more posters here than the world-at-large) begin their retirement savings in their 20s. Sometimes you can get away with it. (My parents started saving for retirement in their 50s and are not retired - not well-off, not even really comfortable, but retired...). The stunning preponderance of evidence is that we CANNOT get away with it in regards to climate change. That when the evidence the deniers (or even well meaning, accepting of reality folks like Peter, looking for the inevitably improved estimates) arrives - the outcomes that are painful and probably not possible to manage will be baked into the pie. We basically need nature to cooperate and throw in some natural-variation-on-the-warm-side or else we can expect more status quo/BAU. If however, fossil fuel prices increase and we have a hot couple of years (El Nino we miss you!) - that might suffice to move people into the take the necessary preventative steps column. This feels like a negative comment, but I am at a loss to justify/explain what people are doing in another way. -
Rob Painting at 07:04 AM on 19 February 2011PMEL Carbon Program: a new resource
Guinganbresil - Rob Painting - I will go out on a limb and say you are way off base saying that upwelling can't cause surface pH drops because the deep water is not showing a pH (or DIC) change. How do you propose this can happen?. If you take carbon from deep water on a global scale and shuffle it up to the surface, then carbon down deep (DIC) will change. There's no getting around this, hence my swimming pool analogy. we are talking about mixing pH 7.6 deep water with pH 8.1 water at the surface - that is a 0.5 pH unit difference... Compare that to the 0.1 pH difference from the whole industrical revolution You still don't appear to be grasping this concept of ocean acidification. Re-arranging the placement of dissolved carbon in the oceans doesn't change to total amount of carbon.
Note that the addition of carbon dioxide dissolving into surface waters is what is causing the increase in total carbon in the ocean (DIC). pH is a reflection of the chemical reactions which dissociates more hydrogen ions from water molecules. I think your confusion stems from failing to understand this point.
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Berényi Péter at 06:50 AM on 19 February 2011The Dai After Tomorrow
#16 Albatross at 04:49 AM on 19 February, 2011 debunking the CO2 is "plant food" myth This is how the myth looks like. Pretty, eh?
Of course soybean is a C3 plant (uses less efficient ribulosodiphosphatcarboxylase enzyme instead of phosphoenolpyruvatcarboxylase to collect CO2 from air). Still, a rather important crop.
In case of drought which plant could collect more water? The one with shorter (a) or longer (b) roots? Place your bets. And then the stomata thing was not even mentioned. OK, it was.
Moderator Response: [Daniel Bailey] Please, no more spamming of this thread. This thread is about drought in a warming world. You have already been directed to more appropriate threads for the topics you've raised here. Future off-topic comments here will be deleted. Thanks! -
The Dai After Tomorrow
Berényi - I have replied on the economic impacts of carbon pricing thread.Moderator Response: [DB] Thank you! -
CO2 limits will harm the economy
Berényi - Benefits look to outweigh costs by a factor of 2 to 8, neglecting benefits such as decreased air pollution, ocean acidification, and overall climate change. Your cost argument does not hold up. -
Rob Honeycutt at 06:11 AM on 19 February 2011A Swift Kick in the Ice
Thank you Peter... That's a really valuable point! -
doggenome at 05:43 AM on 19 February 2011A Swift Kick in the Ice
Another reason is the warm Atlantic Water entering the Arctic Ocean from the Gulf Stream. There is a recent article in Science on this subject. Speilhagen, et al. "Enhanced Modern Heat Transfer to the Arctic by Warm Atlantic Water" by Spielhagen et al. Science (2011) vol 331, pp 450-452 -
Berényi Péter at 05:39 AM on 19 February 2011The Dai After Tomorrow
#15 KR at 04:34 AM on 19 February, 2011 Prevention will always be less expensive than after-the-fact adaptation. You're advocating the most expensive path with that statement. That's obviously not the case. Using the precautionary principle one could easily prevent accidents by banning traffic once and for all instead of the meticulous adaptation process involving crash tests, seat belts, airbags, speed limits and the like, any of which costs money. However, if you compare this cost to that of the mindless prevention scheme mentioned above, it is negligible. -
Peter Offenhartz at 05:38 AM on 19 February 2011A Swift Kick in the Ice
You ask "Why would the poles warm faster if there is so little water vapor in the air?" The answer is in part the changing albedo, as you note, but there is another part to the answer: Rising CO2 matters most when water vapor is lowest. This is because the absorption bands of H2O and CO2 overlap to some extent. The effects of CO2 tend to get swamped out when water vapor concentration is high, but in cold, dry places, CO2 accounts for most of the greenhouse effect. The change in water vapor concentration with temperature is exponential: At 15C and 50% humidity, water vapor is 0.84% of the atmosphere at sea level (by volume or by molar fraction); at -15C water vapor is only 0.08%. And at -40C, 0.006%. -
Rob Honeycutt at 05:07 AM on 19 February 2011A Swift Kick in the Ice
Thanks, The Ville. Fixeded...ed it. :-) -
Albatross at 04:56 AM on 19 February 2011The Dai After Tomorrow
BP, a small but important point, a windmill and a wind turbine are different things which serve different purposes. And we know the game of mixing them up to demean the importance of wind turbines. And the ideological rant at the end of you last post @15, only acts to betray your bias and undermine your credibility. Please save that nonsense should you happen to post at WUWT (or other anti-science sites). -
Albatross at 04:49 AM on 19 February 2011The Dai After Tomorrow
Regarding BP's posts on this thread, The anti-science meme by contrarians and "skeptics" continues. Yes, it appears that the eastern portion of the Mediterranean very likely experienced more frequent pluvial conditions 5.5 to 9.5 thousand years ago which led to sapropel formation. That regional response, has nothing whatsoever to do with the current anthropogenic forcing of global temperatures. Is BP honestly trying to suggest that the the entire Mediterranean region will now (and in the future) respond in the same way it did 5-9 K years ago to even warmer conditions? Ludicrous. First, as Dai et al.(2004) have found using observations, most of the Mediterranean has experienced a drying trend under the current observed warming (see their Fig. 7b). It is already experiencing an increase in drought conditions, and there are othewrs papers which show the same. Example, Xoplaki et al. (2004): "The second half of the twentieth century shows a general downward trend of 2.2 mm month–1 decade–1. In particular the end of the 1980s-early 1990s are well known for general drought conditions over large parts of the Mediterranean. The first canonical mode has been found to be responsible for the decadal and long term variations in precipitation. These decadal and long- term trends follow those of the Gibraltar-Iceland NAO, thus results suggest that long-term changes in Atlantic variability govern Mediterranean precipitation." Second, the contrarians are assuming that the N. Atlantic SSTs are now and in the future going to be similar to what they were during 5.5 to 9.5 K ago, and as shown above, they do play a role. Recent data indicate that the current warmth in portions of the N. Atlantic, are unprecedented in the last 2000 years (Spielhagen et al. 2011). Third, right now global temperatures are equivalent to the warmest conditions observed during the Holocene. We will shortly almost certainly be warmer than the warmest conditions experienced in the last 10 K years. Fourth, even in the highly unlikely event that portions of the Mediterranean do experience increased rainfall, what about the increase dimpacts of evoporation from higher temperatures, and what about the the rest of the globe? Fifth, BP need to familiarize himself with the permanent wilting point, and the many studies which show that elevated CO2 does not benefit all plants equally (with those using the C4 pathway, which tend to be found in hot and drier regions, benefiting the least, if at all). Not to mention the impacts of heat stress on plants. More information debunking the CO2 is "plant food" myth can be found here, and here, and here. And let us not forget the impact of fire on vegetation-- although I concede that is a tough one to weed out because of humans initing more fires, but in regions experiencing drying, controlling those fires will be more difficult. If BP claims to know better than Dai et al., and claims to know what the projections should be, then I challenge him to publish a paper making his case. His posts are nothing more than an elaborate attempt to obfuscate and mislead (e.g., his comments about CO2 enrichment).
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