Recent Comments
Prev 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 Next
Comments 124451 to 124500:
-
Riccardo at 06:24 AM on 5 February 2010Sea level rise is exaggerated
Arno Arrak, we all know that Al Gore didn't quote any time span for the 20 feet rise. We all also know for sure that the sea level will not stabilze by the end of this century. Comparing Al Gores number with a one century rise is (intentionally?) misleading. -
Riccardo at 06:16 AM on 5 February 2010On the reliability of the U.S. Surface Temperature Record
jpark, ironically, the question asked by Pielke Sr. and you has an answer in the very same post. When he quotes Willby paper to assess the UHI effect in London, the very same comparison can be used to check for a difference in the trends. I don't know if Jones at al. used these two stations, but for sure this is the way UHI effect on a trend is checked and corrected for, if any. -
Pat T at 04:54 AM on 5 February 2010The hockey stick divergence problem
This just seems like a pattern - when the evidence doesn't support the theory as you've written it, you change the evidence instead of the theory, when it would take only a minor adjustment to the theory to maintain its viability. It's very stubborn, it's unnecessary, and ultimately it detracts from your credibility. Tree ring width is affected by many factors besides temperature. Tree growth is obviously affected by many factors besides temperature - predators, sunlight, water, etc.... You can throw up these other remote possibilities but the obvious explanation is that the linear relationship between tree ring width and temperature breaks down above certain temperatures, which means that the absence of wider tree rings during a given period doesn't mean it wasn't warmer then. Why go to all the effort to string together an alternative thesis just so you won't have to budge on the "hockey stick" when you don't need the hockey stick? Sometimes you're wrong. It's better for your credibility to admit it and move on. It's clever, it's lawyer-like, to come up with "well the divergence must be anthropogenic too" but it's transparent. Don't risk losing credibility over a sub-issue that isn't necessary to make your larger point - - don't lose the forest for the trees!Response: I think a few clarifying points are in order as many misconceptions re the hockey stick still prevail:- The hockey stick is not dependent on tree-rings. There are a number of proxies independent of tree-rings that give the same result.
- The hockey stick is not the smoking gun proof of human caused global warming. It shows past temperature change, not what's caused it. Sure, it's suggestive and visually persuasive but from a scientific point of view, it does not constitute proof.
- The reason tree-rings are considered reliable before 1960 is because there is close correlation between tree-ring proxies and the instrumental record for the periods where the two overlap (Briffa 1998).
- Personally, I have no emotional investment in the hockey stick. If it turned out it was erroneous and past climate change was greater than currently thought, this would mean climate is more sensitive than we currently think. This means the climate response to the extra heat trapped by CO2 will be even greater.
- Lastly, the peer review science doesn't say the divergence MUST be anthropogenic. It says the "decline in tree growth may have an anthropogenic cause". As the cause is yet to be definitely defined, it's speculation at this point. Similar to the hockey stick, it's not hard proof but it's suggestive.
-
Svatli at 04:28 AM on 5 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
I'm always surprised when the "argument", "that it's all a lie" comes in to the discussion. But to adress the problem at hand. My view of these matters is that the world is warming up, as the science is making clearer to us by various studies. In the future (even now) there will be climate changes as a result of this warming. Of course there are some uncertanties about how these changes will be in the future, expecially if we are talking about some specific areas (like the Amazonas). But also these changes in climate will have some consequence in the future and science is trying to adress those questions as well as possible, with scientific studys. Of course there will be some mistakes made, but overall I don't think the mistake is the big issue (and of course we'll have to learn from them). With all this noise beeing produced by some "critics" it's going to take more time then it should, but if that's the process we have to go through, well then thats what we'll do. It's amazing how some arguments do evolve and how the small issues are sometimes made to look like as they are the whole picture. The big picture in my mind is that the climate is changing because of human emission of CO2, there will be consequences of these changes, but how severe is up to us, because we are starting to get the pieces together to make the big picture even better. -
Pat T at 04:18 AM on 5 February 2010The hockey stick divergence problem
Man-made divergence? That definitely falls into the "oh come on" category. The divergence problem is "unprecedented" and therefore must be anthropogenic? That's quite a reach. The most logical explanation would seem to be that the relationship between tree ring width and temperature changes above a certain temperature level - the level experienced in the 1960s. That means that tree rings are a useful proxy for temperatures up to that level. It also means that tree rings are not useful beyond that level - i.e., it means that when it's warmer than it was in the 1960s, it's not going to show up in tree rings, thus the fact that tree rings don't show higher-than-1960s-temperatures during past periods doesn't mean it wasn't warmer during those periods. And when you take the tree rings out of the equation, voila, the pre-hockey-stick climate history re-emerges. Does the inability to rewrite the climate history preclude man's involvement in the climate changes that have occurred over the last century? No. But the effort to rewrite the climate history adversely affects the credibility of those arguing that man has been deeply involved in those recent climate shifts. So why go through the effort? Tree lines were higher in mountain ranges around the world, including the Sierra Nevadas and Alps. The droughts were so severe in North America that they were a factor in forcing the Anasazi to abandon their elaborate cliffside dwellings. American Indian legend holds that the buffalo migrated far to the north to richer grassland. The Vikings sailed the North Atlantic in wooden boats on ice-free waters (that would during the 14th century become choked with icebergs - i.e., from sea ice breaking off much like today) and maintained a colony on Greenland - and the settlers' diets were for 200 years 80% land-based. They maintained vineyards in England (and the fact that after 900 years of breeding new varieties of grape and improving technology for cold-hardiness British wine production has reemerged is really not a counterpoint). Olive trees in Cologne. Glacial retreat in the Alps is revealing archaeological finds from the MWP - items left behind by traders using mountain passes only now resurfacing. Lake Naivasha in Kenya dried up for 200 years. Further evidence has been found in Mongolia, Japan, the Arctic and Antarctic. And don't forget the countless contemporaneous observations. These have not been explained away as having occurred for reasons other than warmer temperatures, and they cannot be dismissed as "merely anecdotal evidence." These examples all occurred during the 1000 AD - 1200 AD timeframe. That there were a few cold years in between is about as relevant to the "geosynchronous" nature of the MWP as the fact that the United States had its third coldest October on record last year is relevant to geosynchronous warming now. Even if some combination of boreholes and other indirect evidence indicates an MWP slightly cooler than late 20th century temperatures, we still have an MWP plateau that lasted for a few centuries within a few tenths of a degree of the peak modern warmth to date. Rather than try to downplay this or write it out of the climate history altogether, why not simply accept it and try to make the case that the 20th century warming is different because its suspected cause is something that won't reverse itself, which means that it will continue? Why not also point out that since what caused the MWP isn't fully understood, there's every reason to expect that it could reoccur - and that the combined effect of increased CO2 plus whatever naturally caused the MWP would be severe? You might be less able to make a case that we're only a few years away from a "point of no return" but nobody believes that and it's a risky argument anyway - when those few years pass but the point of no return doesn't, it will simply fuel more skepticism. There are a lot of skeptics who would be more open minded about AGW if it weren't for some of the overstatements and misstatements made by the more zealous of AGW supporters, including the efforts to rewrite the climate history. The Hockey Stick has done the AGW proponents more harm than good - when you mess with the established history, you create skeptics of your theories as to the present and future. -
Berényi Péter at 04:14 AM on 5 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
Arno Arrak at 02:50 AM on 5 February, 2010: "That the Brazilian forest is sensitive to drought is not a world-changing revelation. [...] idiotic policies that have no effect on climate but [...]" My understanding is that there is not much trend in rainfall over the Amazon basin during the last 60-80 years. If anything, it is increasing slightly. And draught is draught, it just happens every now and then. It is not even true, that biomass decreased there in 2005 tremendously. In most parts of the basin phosynthesis even inreased due to more light from cloudless skies. That is, water availability was not a limiting factor. Deforestration and wildfires is clearly a problem and it is a man-made one. Not through global warming though, but irresponsible land use practices by large corporations whose business is government subsidized biofuel production (soy bean diesel & sugar cane methanol). It is not that Amazon should be left alone. In fact it could support a large population, just some ancient practices are to be picked up again. About 10% of the basin is covered by terra preta, an up to 2 m deep, tremendously fertile black anthropogenic soil, made by a large population between 450 & 1500 AD. Five hundred yers ago most of the people were exterminated by plagues brought in by conquistadors. The rest were hunted by slavers, escaped to forest. Most of the so called primitive tribes there are in fact offsprings of refugees, deprived remnants of a higher civilisation. Considerable part of the basin is not native forest, but an abandoned garden. Terra preta, even after five hundred years with no further care, turned out to be self regenerating. It keeps growing into the barren clay below. The long forgotten technology to create terra preta do indio is already rediscovered, it could also be reimplemented. -
Arno Arrak at 04:09 AM on 5 February 2010Sea level rise is exaggerated
Can I point out that your statement about rising sea level is false? B. F. Chao, Y. H. Yu, and Y. S. Li (Science, 320:212-214) have shown that sea level rise for the last eighty years has been linear, with a slope of 2.46 millimeters per year. Theirs is the sea level that has been corrected for the effect of water held in storage by all dams built since the year 1900. Something that has been linear this long is not likely to change anytime soon. Which means that you can be a futurist and predict that sea level will rise a little under ten inches in a century, not twenty feet that Al Gore is still peddling in his movie.Response: Arno, thanks for bringing our attention to that paper which actually shows that the situation is worse than I described. The paper is Impact of Artificial Reservoir Water Impoundment on Global Sea Level (Chao 2008). It reconstructs how much water has been impounded in water reservoirs since 1900. The amount of water stored skyrocketed after 1950. If this hadn't occured, sea level would've been even greater. Consequently, they calculate what global sea level should be after accounting for reservoir impoundment water. They then compare their results to actual observed sea level:
What they find is the increase in the rate of sea level rise is actually greater when you factor in water impoundment. This increases the significance of retreating ice sheets. A sobering result, considering the accelerating ice loss from Antarctica and Greenland. -
danielbacon at 03:37 AM on 5 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
You could also add Hutyra et.al. 2005 “Climatic variability and vegetation vulnerability in Amazonia†to your list too. http://eebweb.arizona.edu/faculty/saleska/docs/Hutyra05_Var.Vuln_GRL.pdf -
jpark at 03:04 AM on 5 February 2010On the reliability of the U.S. Surface Temperature Record
Leo I think he used Reno because the National Weather Service includes the UHI factor in one of it’s training course using Reno, NV. So says Watts anyway. But this is quite a shock from Pielke blog (link below) where Phil Jones (et Al) is quoted as saying "London however does not contribute to warming trends over the 20th century because the influences of the cities on surface temperatures have not changed over this time." Pielke says: 'However, how would they possibly know that? The assumption that any temperature increase in the last couple of decades in London is not attributable to an increased urban heat island effect, at least in part, needs be documented, for example, by satellite surface temperature measurements for the more recent decades when they are available.' http://pielkeclimatesci.wordpress.com/2010/02/04/the-urban-heat-island-issue-the-released-cru-e-mails-illustrate-an-inconsistency/ -
Miriam O'Brien (Sou) at 02:36 AM on 5 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
It's my understanding that the IPCC reports themselves are reviewed. Each of the 2007 reports lists a very large number of reviewers. I also thought I saw written on realclimate.org that for at least some of the WG docs the guidelines do not stipulate that all references must only come from peer reviewed journals. I don't have a problem with that provided the IPCC review process works well. The current kerfuffle is likely to result in one of two things: either relevant material will be omitted because, while known, it has not been published in a peer reviewed journal; or material such as potential impacts will be included that are not referenced at all but simply checked by IPCC reviewers for accuracy and relevance, based on their personal knowledge. Neither of these is satisfactory to my mind. I hope that any review of drafting and review processes does not result in important information and likely impacts under specific scenarios being omitted from future reports. -
HumanityRules at 01:36 AM on 5 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
And this for a historical view of rainfall in the amazon basin. http://www.scielo.br/pdf/aa/v35n2/v35n2a13.pdf -
HumanityRules at 01:05 AM on 5 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
Isn't this a bit of a tautology. Surely by its nature a rainforest ecology is going to be affected by reduction in rain. Just like a saltwater marsh would be affected if its no longer inundated by seawater or a lake system is affected by in flow from rivers. The question is what is the relevance to climate change, what's causing the drying? The 1999 paper specifically links the drought to the 1998 El Nino. There are papers which show that fire has played an important part in amazonian rainforest for over 6000 years. Holocene fires in the northern Amazon basin. Saldarriaga, JG | West, DC Quaternary Research [QUATERN. RES.]. Vol. 26, no. 3, pp. 358-366. 1986. The paper puts forward the hypothesis that there have been "unstable environmental conditions" for >6000years in the Upper Rio Nagro region as evidenced by dated charcoal in the soil. Also http://jisao.washington.edu/data/brazil/ Do you see a trend or fluctuation? Peer-review or WWF is a red herring. The question is relevance. -
chris at 00:43 AM on 5 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
chriscanaris, this is a pertinent paper (see below). It addresses the latitude-dependence of expected changes in precipitation in a warming world, and compares this with the observational evidence. The observations and predictins are that the central latitudes experience increased drought in a warming world, whereas the higher latitudes will experience increased precipitation. The region from the equator to ~30 oN is the particularly vulnerable region that is expected to dry fastest, and this has already been observed during the observational period (1925-1999). X. Zhang et al. (2007) Detection of human influence on twentieth-century precipitation trends Nature 448, 461-465 http://www.nature.com/nature/journal/v448/n7152/abs/nature06025.html -
CBDunkerson at 00:05 AM on 5 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
chriscanaris, it is fairly obvious that higher temperatures will lead to increased evaporation of surface water and greater quantities of atmospheric water vapor (since the amount of water air can hold increases with temperature). From there it also seems clear that increased atmospheric water vapor will lead to increased precipitation - though not necessarily in direct proportion. However, it needs to be understood that these are localized phenomenon. Increased evaporation drying out scrub-lands is helping the Sahara desert to grow... because that extra evaporation is not offset by equally increased rainfall in northern Africa. The same is true of glacier loss all over the world... higher temperatures are leading to increased melt rate. That extra flowing water does mean increased precipitation, but it is spread out around the world rather than all falling back onto the glacier to replace the mass lost to melting. So your question of whether global warming will lead to a 'wet world' or a 'dry world' isn't really on point... the hydrologic cycle will certainly continue to intensify, but that will result in some areas becoming drier and others wetter... rather than increased evaporation and melt being perfectly offset by increased precipitation in each region. -
chris1204 at 22:28 PM on 4 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
Thank you, Alexandre - a fascinating paper. It's an amazingly complex system with many unknowns. Deforestation seems to be a major culprit and perhaps an amplifier of AGW impacts. -
Alexandre at 21:46 PM on 4 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
Oh, sorry for the poor citation: Marengo 2006 On the Hydrological Cycle of the Amazon Basin: A historical review and current State-of-the-art -
Alexandre at 21:45 PM on 4 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
Since we're talking about the Amazon, here's a Brazilian paper (in English) on water vapour recycling in our rainforest. Climate change is projected to shift rainfall from Amazonia to the La Plata river basin, inducing a permanent El Niño-like behaviour. http://www.rbmet.org.br/port/revista/revista_dl.php?id_artigo=202&id_arquivo=352 -
chris1204 at 21:33 PM on 4 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
Nevertheless, I really would love to know whether we're likely to be looking at a warm wet world or a warm dry world as it makes a world of difference - pardon the pun. I note the Phillips paper states, ‘Tropical droughts may intensify and become more frequent this century as a result of anthropogenic climate change...’ However, I wonder if this automatically follows if stratospheric water vapour increases. I certainly do have some understanding of probability - a very salient part of my professional field (psychiatry) but I am no climatalogist. However, I hope I can still ask a halfway sensible question. So might increased stratospheric water vapour lead to increased precipitation or does only tropospheric water vapour count? I ought to add that I spent my childhood years 5 degrees north of the equator in West Africa – very warm and very wet! Moreover, Freddy Norton might see dry stressed eucalypts outside assuming he’s living in southeastern Australia (as I do now) – he would encounter a very different environment if he travelled north to the Cape York Peninsula where lush tropical rainforest abounds. As an aside, I note the Phillips paper also says with appropriate caution: ‘We find that relative drought is indeed strongly implicated as the driver of the network-wide shift in forest behavior (Fig. 2) but that the absolute intensity of the 2005 dry period was only weakly related to biomass dynamics... Those forests experiencing the most elevated moisture stress relative to their long-term mean tended to lose the most biomass relative to their pre-2005 trend (Fig. 2). These losses were driven by occasionally large mortality increases and by widespread but small declines in growth. Our method may fail to capture growth impacts well because intervals were longer than the period of potential moisture constraint, thereby masking its effects (drought can kill trees but can only temporarily stop growth).’ Incidentally, Phillips also states: ‘However, our findings do not translate simply into instantaneous flux estimates because carbon fluxes from necromass will lag the actual tree death events.’ This raises the further question of whether ‘necromass’ truly just ‘deadwood’ or is it in fact an intensely complex ecosystem made up of microscopic biomass with its own carbon dynamics and carbon sink properties? Given the exceptional nature of the 2005 drought, I wonder if we don’t run the risk of making long term forecasts based on a single event akin to popular assertions that the severity of the recent northern hemispheric winter ‘disproves’ AGW. It would be more pertinent to ask what is happening to the rainforest five years down the track. Quite a few questions, I know. Any ideas from anyone out there? -
Arkadiusz Semczyszak at 21:17 PM on 4 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
Already professor S. Stanley in the "old" textbook: "Earth System History", 1999; for example, African gorillas, and another; reported by high climatic stability of the tropics ... It’s for this, also, in the process of evolution of the coral is not created to adapt to large changes in temperature. This tropical thermostat - it is obvious for climate students... but not for the IPCC ...? -
Doug Bostrom at 18:32 PM on 4 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
chriscanaris at 18:24 PM on 4 February, 2010 "I am wary of attributing all environmental problems to AGW" More really a matter of probabilities than definite assignment, and that's where error bars really help. Unfortunately error bars or the equivalent are the very first thing generally stripped away in communications styled for the general public, a shame because they're not at all hard to understand. I think journalists give too little credit to the average reader's ability to keep up. If you're sucked in by the headline and lede, you're probably going to stick around for the whole story as long as it is not egregiously dense. -
chris1204 at 18:24 PM on 4 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
Which raises the question of whether the Amazonian drought can be blamed on AGW. The last post on this site dealt with the connection between AGW and stratospheric water vapour. The question is – does increased water vapour lead to increased precipitation? If so, then the Amazonian drought may have its origins in more complex mechanisms. I am wary of attributing all environmental problems to AGW – this detracts from sober assessments of the issues and provides ammunition for those who might have an axe to grind. -
RSVP at 18:13 PM on 4 February 2010The role of stratospheric water vapor in global warming
to doug_bostrom "I have neither common sense nor a reputation" ...give yourself more credit. Your reasoning is superb. One of the nice things about having anonymity, as on this site, is that ideas can be shared without fear of damage to reputations. Personally, for a question as large as global survival, its hard to understand how that can even be a priority. At any rate, I believe the truth ultimately "speaks for itself" and will lead humanity in the right direction. But then again, a lot of opportunists will be found along the way. -
RSVP at 17:51 PM on 4 February 2010The role of stratospheric water vapor in global warming
Marcus I wrote... "For this reason, it is unlikely for a non skeptic to look for such a correlation, and that any detectible change would have to be coming from natural forcings" then you wrote... "this slower warming rate occurred against a backdrop of a significant drop in Total Solar Irradiance-to levels unseen in over a century" And I cant prove it, but I also KNEW somebody would reply with something like that about China & India. You cant have it both ways. Either it helps to cut back on fossil fuel consumption or it doesnt. The world is never going to get there if everyone is thinking, "well I cant stop this because someone in China is now polluting in my stead", or visa versa. Similarly, it is counterproductive in terms of global morale to be concerned with what the Sun is doing. I cant believe me the skeptic is saying this, but maybe the science behind all this will need to be censored in order to achieve the desired goals. -
Doug Bostrom at 17:47 PM on 4 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
The first full explanation of this matter I've seen. Thanks! C&T legislation coming up here in the USA, maybe, and whether that happens will depend a lot on what sort of noise level can be generated by extracting "gotchas" out of IPCC as well as whatever other scat can be flung at climate science. Our legislators here seem to be going through a period of natural or forced variation where the "courage index" is at historical lows, so they'll take any excuse possible to remain sitting on their hands when it comes to serious attacks on carbon. So this is a year-- maybe the first of a few in a row-- where we'll see all the stops pulled out; fossil fuel interests have so much at stake in their battle to avoid us becoming accountable for C02. Readers here may not be aware that even as Dr. Mann is vindicated after Penn State managed to construct a coherent set of inquiry points from skeptic complaints, a new and massive round of FOIA requests are being volleyed by the "Competitive Enterprise Institute".* The very filing of these is eagerly reported by news outlets, regardless of merit, as they feed an air of scandal even where none exists. Some climate scientists are even being sued in connection with their right to free speech.** When it comes to "dragging politics into science", remember where the real political machinations are coming from: CEI, The Heartland Instute, those are the kind of entities projecting politics onto science. No need to imagine scientists engaged in conspiracies, you can read about the real plans in your newspaper, nearly every day. What we're seeing are a number of unwitting researchers blundering onto a stage while pursuing their inquiries, doing what has turned out to be the "wrong" kind of investigation. The stage is filled with actors armed with real swords. It's not a pretty scene, not at all. * http://dotearth.blogs.nytimes.com/2010/02/02/climate-information-wants-to-be-free/#more-13879 http://docs.google.com/fileview?id=0B88iFXWgVKt-Y2VjMTdlNTQtMmJjNy00ZjhkLTkyYTItMzA1Yzc2OTZkYmFi&hl=en ** http://climateprogress.org/2009/11/25/competitive-enterprise-institute-to-sue-realclimate-blogger-over-moderation-policy/ -
David Horton at 17:44 PM on 4 February 2010What the IPCC and peer-reviewed science say about Amazonian forests
Blind Freddie knows forests, whether in the Amazon, or Australia, are stressed by drought and high temperatures (not to mention fires). From my window I can see Eucalypt forest which visibly changes appearance (I presume as leaves fall, or change orientation, or are reduced in size, or change colour) under extreme conditions. This rubbish about IPCC failures is again (like Himalayan glaciers) a piece of nonsense about the messenger while ignoring the message. "Peer Review" has become one of those terms which is just tossed around, contemptuously by deniers, with approval by those in the real world. I've always thought of the review process not as some magic bullet, removing all error, but as a way of getting your work looked at by someone familiar with the field, who can (a) have some chance, because of familiarity with the field and its literature, spot errors in references, or possible errors in tables, or see some error in logic, and (b) reassure you that you are not living in some alternative universe. Non-peer-reviewed material is the shock jock on the radio, Monckton at the press club, Plimer's book, most blogs (although in a sense the comments on a blog piece are a form of peer review, as long as your readers are not all raving lunatics). These are just statements made, out of someone's thought processes, or whacky experiment, which sees publication without anyone else getting to check it. Non-peer-reviewed papers may occasionally be right, of course, peer reviewed ones may retain errors (no one really knows the details of your subject as well as you do). It's all a bit like the difference between getting a PhD after being vetted by your supervisor and three hot shot examiners, and getting a PhD by filling in a form and sending money to an internet site in Uzbekhistan. -
Doug Bostrom at 12:08 PM on 4 February 2010The role of stratospheric water vapor in global warming
Marcus: "First off there has been *no cooling* for the last 10 years, just a slower rate of warming than what we saw between 1980-1999." And it's great that Solomon's paper advances a possible explanation for this. Beyond Solomon, there is no identified mechanism to explain why the Earth should appear to have undergone cooling during the past decade. More, for that matter there is not even a means to explain a slowdown in warming of the size we've seen, not one on which anybody's prepared to stake their reputation. Solomon explains perhaps 25% of the budget problem, leaving a hole that while not a complete mystery is not actually attributable on a quantified basis to any of several possible candidates. Consider for a moment that the first 3 meters of the ocean contains as much heat energy as the entire atmosphere, that the ocean has an average depth of some 3,800 meters, with the vast bulk of that water exchanging heat with the atmosphere as well as directly absorbing much larger amounts from insolation at greater or lesser rates. The upper 90m of ocean alone introduces potentially years of delay for measurable surface temperature changes in response to forcings. Now remember that our ability to measure ocean heat content is patchy while our understanding of the movement of heat into the oceans particularly as water and heat goes deeper via thermohaline circulation is by no means perfect. We can't say on an annual basis or even over a number of years how much energy the ocean will suck up in a way that keeps the ever-so-wispy atmosphere cooler than it would be without the ocean sink. We obsess about surface temperatures while in point of fact a miniscule fraction of the energy imbalance predicted by climate science is actually available for measurement at the surface. Most of the energy is going into the ocean, at greater or less rates over time, where it may be hidden for greater or lesser periods of time. I don't think anybody with common sense and a scientific reputation to protect will make a firm prediction about the ocean heat sponge vis-a-vis the past decade in the absence of more actual data. I have neither common sense nor a reputation, so I'll say that in years to come we'll likely find there was little total change in the radiative budget during the past decade and that instead this heat has been temporarily "lost" in the ocean. More on ocean: http://www.oco.noaa.gov/index.jsp?show_page=page_roc.jsp&nav=universal -
Marcus at 11:18 AM on 4 February 2010The role of stratospheric water vapor in global warming
RSVP. First off there has been *no cooling* for the last 10 years, just a slower rate of warming than what we saw between 1980-1999. Secondly, this slower warming rate occurred against a backdrop of a significant drop in Total Solar Irradiance-to levels unseen in over a century. It had little to do with economic activity, given that 2001-2007 marked a large upswing in economic activity in most parts of the world-especially China & India (the GFC is only a very recent event after all). So your theory about warming being potentially due to industrial waste heat doesn't actually bear up to close scrutiny. Even so, turning waste heat from industry into electricity is a good idea because it reduces both thermal pollution (which, IMHO, is a problem we should be tackling) whilst also reducing our dependence on fossil fuels as an immediate source of electricity. -
RSVP at 10:50 AM on 4 February 2010The role of stratospheric water vapor in global warming
The warming period happens to coincide with a period of economic boom (the 90s), while the cooling comes after ten years of economic crisis. It is well known that the affluent heat polluters of the planet have had to curb their spending habits in direct relation to the crisis and increased fuel prices. On the other hand, if the effects of CO2, as the theory goes, has such a prolonged hysteresis (in the order of hundreds of years), changes in life style within this ten year span shouldnt make a dent in temperatures. For this reason, it is unlikely for a non skeptic to look for such a correlation, and that any detectible change would have to be coming from natural forcings. (If this recent cooling is indeed due to a slowed down global economy, it would suggest extra warming is due primarily to industrial waste heat.) Without jumping to conclusions, this touches on the issue of climate response, or what has been referred to in other posts as sensitivity. If an Earth Year was conducted (like Earth Day except for a year, and with participants truely not burning any fossil fuels), and if after that year, global cooling was detected, an index for the Earth's response to human industry could be determined, where a faster response would indicate higher sensitivity, and a slower response, lower sensitivity. Ironically, higher sensitivity would be bad, since it would indicate a need for drastically curbing human industry. On the other hand, low sensitivity would also be bad, because it would indicate that we have little or no control of this situation. More ironic still is that I am supposedly a skeptic. -
Berényi Péter at 10:05 AM on 4 February 2010The role of stratospheric water vapor in global warming
CO2 does play an important part. In tropical lower stratosphere (~15 km), above low level clouds it has a vehement cooling effect. Temperature there can get as low as 190 K. Air becomes absolutely dehydrated (0.2 ppmv dihydrogen monoxide). Up there CO2 is the main agent, capable to radiate heat out to even cooler (2.7 K) space. The more CO2 is in the atmosphere, the more dryfreezed air is produced this way. If subsequently it gets mixed into upper troposphere by whatever process and drifts over a cloudless area, a wide IR window is opened, an effective heatsink to space. http://asd-www.larc.nasa.gov/~tak/wong/images/NationalGeographic/ceres_aqua_olr3d_20030804_s.png -
Riccardo at 09:55 AM on 4 February 2010Is Pacific Decadal Oscillation the Smoking Gun?
Feet2thefire, nice description of an important decadal variability contribution, second only to ENSO probably. You only did not mention that together with the warm phases there are negative phases and that's why it contributes to variability but not to the long term trend. Indeed, PDO has been in a neutral/negative phase during the last and warmest decade on record. As for the models, do you think that in 20 years nothing has changed? And, above all, models can not "include" PDO, the may show a PDO-like pattern of variability as some (not all) of them actually do. -
Riccardo at 09:19 AM on 4 February 2010There is no consensus
oracle2world, Nobel prizes are awarded only after a consensus is reached and Stanley Prusiner had to wait 15 years. Contrary to popular belief, this is how science works, a ground-breaking theory on something not yet explained emerges but it needs to convince the other scientists before it is accepted and form a new consensus. In real science there's no definitive proof but a (growing) amount of evidence. -
Vinny Burgoo at 08:45 AM on 4 February 2010The IPCC's 2035 prediction about Himalayan glaciers
Don't bother bothering the authors further, Charlie A. The ultimate source of WG2 Ch10's bogus and unsourced 135.2 m/a Pindari retreat claim is a 1981 book entitled _The Himalaya: aspects of change_ by Lall and Moddie. (This source was predictably hard to pin-dari down. The intermediate sources that the WG2 authors most likely used said that the claim came from a study by the first Indian to climb Mount Everest called, somewhat daftly, 'Himalayan Glaciers in the Himalaya', editors Lal and Moodie.) This book is viewable only in Snippet mode in Google Books but that's all that's needed. A search with 'Pindari' returns the relevant portion of a table. Name of glacier: Pindari Period: 1845-1966 Rate of retreat, M/yr: 23.5 Yet more climatic Chinese whispers. Well spotted, Charlie! -
Feet2thefire at 06:39 AM on 4 February 2010Is Pacific Decadal Oscillation the Smoking Gun?
"The long term warming trend indicates the total energy in the Earth's climate system is increasing. This is due to an energy imbalance - more energy is coming in than is going out (Hansen 2005)." This may not be the case at all, although may not be obvious to everyone why not. And I am just throwing this out there to point out that we tend to accept what seem like obvious black-and-white preconceptions because we don't think of everything. It could be just a rearranging of the energy distribution. It could be that enough heat energy is sequestered in the deeper ocean (such as the Northern Pacific), and it only rises to the surface under certain conditions. Those conditions may be currents or wind patterns that change, for shorter or longer periods. ENSO is already understood to be a change in the wind currents (although the currents, too, might actually be an effect, not a cause). The heat signature (for satellites) of ENSO represents HUGE amounts of heat energy that does not appear to come from anywhere. It doesn't come from the Sun, so it must be heat coming up from the abyss. Perhaps the prevailing currents from Peru push the warmer water down (I know, that seems counter-intuitive.) But where does the heat come from, if not from the Sun? And if it does not come from the Sun, then it is not part of the albedo/energy In-Out balance. At least not in any way we currently know of. Back to the climate, as it applies to the PDO especially, the heat energy under the ocean may well up for periods, bringing more heat energy to interact with the atmosphere. This is all speculation. But I've been following the PDO since right around 2000, and wondered for quite a while when scientists were going to start to realize that climate theories and models that don't include the PDO simply cannot possibly be correct. The Pacific Ocean is the bull in the china shop, as far as climate goes. The Pacific is about 30.5% of the surface area of the planet - more than all the land area put together. It is fully FIFTEEN times as big as the United States. What happens out there, energy wise, in the Pacific dwarfs everything else. And then consider the 1/30th of 1% of CO2 in the atmosphere and the 5% or 2% of CO2 that humans create. How totally insignificant our activities are in comparison. The climate models upon which AGW were originally based were created in the early 1990s. This predated the discovery in 1997 of the PDO, so they could not have included the PDO. And if they don't, those models were (and are still, I believe) fundamentally wrong, because they were missing a huge factor, the PDO. One would have to think that it will be a decade or three of four before we adequately understand the PDO well enough to even approximate it in the models. -
SNRatio at 05:07 AM on 4 February 2010The role of stratospheric water vapor in global warming
What is the likelihood of CO2, methane etc playing no part in the processes discussed here? Not very high, I would say - to some extent, SWV content seems to be part of a positive GHG feedback. But this is not a fixed, well defined functional relationship, rather it has a stochastical nature, with considerable variance, and several other factors influencing. In some situations, it may even turn out to be negative. -
oracle2world at 05:04 AM on 4 February 2010There is no consensus
"Consensus" has little meaning in science. Ground-breaking science is by definition outside the prevailing consensus. Consensus just means it is easier to publish your work. Prions were hotly disputed, and the idea of an infectious protein is about as jaw-dropping as it gets, but subsequently Stanley Prusiner won the Nobel prize for his research. Science simply consists of explaining the most data with the least long-winded explanation (aka Occam's Razor). We use the model that the earth orbits the sun because the math becomes neat and tidy using this assumption. With the earth at the center, the math becomes intractable very quickly. However, when discussing hurricanes and naval guns, folks like to assume the earth does NOT rotate, and a fictitious force called the Coriolis force must be introduced to correct. We assume the earth is flat for laying out a garden, but need a spherical model to use for space travel. Physics uses the wave theory of light in optics, and organic chemists use stick and ball models, knowing they are incorrect, but convenient, models. Everyone clear on what science is now? The Asch conformity experiments in psychology show people will knowingly lie to conform when comparing lines on a piece of paper. No ambiguity. Other experiments show the less people know about a topic, the more they conform. What happens when you have an enormously complex chaotic non-linear system (aka climate) whose inputs and outputs are not well understood, and conclusions are presented as unequivocable? The bottom line is that climate science is a bit flakey from the get-go, the data have enormous variance, and the field is not helped by over the top WAG predictions a hundred years out. The only reason it appears to have any traction, is because mankind can be blamed. There are far worse end-of-the-world-as-we-know-it scenarios with much better data, approaching almost certainty, that would merit more time and resources. Any questions? -
Doug Bostrom at 04:38 AM on 4 February 2010Lessons from the Monckton/Plimer debate
fimblish at 20:23 PM on 3 February, 2010 That's a horribly vaguely worded assertion by Monckton. Short answer: with a 30% cut we'd still be pumping up the C02 content of the atmosphere, adding to the basic physics problem. There's no reason to even to imagine the temperature would decline, let alone show it on paper. "Not even wrong", as some wag at RC says. So Monckton is making an attack on morale, a "psyop" thrust as the military would say. -
Berényi Péter at 20:53 PM on 3 February 2010The role of stratospheric water vapor in global warming
@44. Marcus at 13:41 PM on 3 February, 2010 "whether increasing SWV" Marcus, the Solomon paper is not about increase, but an abrupt global drop in lower stratospheric specific humidity. If it occurs every now and then, it can provide an overall negative long term water vapor feedback loop in spite of positive feedback in the short run. Dynamics just like bubbles bursting, both real ones and those created by stock excange. Also, it makes pattern recognition based data homogenization techniques specific to mainstream climate science untenable. Climate does have temporal patterns, even sharp steps. They are not to be removed from data series but to be observed. -
fimblish at 20:23 PM on 3 February 2010Lessons from the Monckton/Plimer debate
According to Miranda Devine (SMH), Monckton has claimed that if every nation were to cut carbon emissions by 30% over the next 10 years, the decrease in mean global temperature would be a mere 0.02 degrees. Is this true? -
Riccardo at 19:06 PM on 3 February 2010Understanding Trenberth's travesty
Hence the single station measurement is equivalent to a local measurement in the pot; it must be corrected with a nearby stations if for any reson locally there has been an unjustified jump. If the jump is real, it shows up in nearby stations also. It's so true that there are non climatic jumps that the corrections average to zero globally. As always, people like to discredit stations measurements with no real reason, just becasue it's "usefull to the cause". -
HumanityRules at 17:08 PM on 3 February 2010The role of stratospheric water vapor in global warming
Chris #42, It's not just the coincidence of cooling for the last 7-10 years but also the coincidence of warming from 1980-2000. From reading past stuff John has posted and comments I've got several impressions. 1)The warming from 1980 to 2000 (or beyond, take your pick) is the most obvious, significant and fastest and has given us projections for the future. 2) Prior to this nothing else has coincided with the warming trend, solar/ENSO etc all breakdown at some point. For this reason CO2 has been blamed for most of the warming over the past 30 years. Thats not to say CO2 doesn't cause warming but you have to conclude that the present discussed process is contributing a not insignificant amount which has to come from warming that was previously attributed to CO2. I agree you can't overturn a whole idea based on one paper (although I didn't see this complaint discussing Mennes 2010) but there's no problem with acknowledging a role and speculating on the implications. While the temp record maybe 150years long, most other processes discussed here and elsewhere have much shorter data runs, take arctic sea ice melting for example. Separating trends from fluctuations is an issue with many climate related topics. -
Arno Arrak at 14:32 PM on 3 February 2010Lessons from the Monckton/Plimer debate
Looked at Dana Royer's paper on climate sensitivity for the past 400 million years that you refer to. What a great snow job it is! This is apparently where part of that billion dollars of climate research money goes. Running a total of 10,000 GEOCARBSULF simulations for each one of his delta-T(2X)values on a supercomputer does not increase my confidence in his values, just shows that he can do it. The paper basically tries to model carbon dioxide role through the ages and comes to the conclusion that climate sensitivity has been about 1.5 degrees Celsius for the past 420 million years. He shows nice computed curves but it is hard to understand what they mean and totally impossible to check or repeat any of his work. We know that both temperature and partial pressure of carbon dioxide have varied throughout geologic time but we learn nothing about either one of them. Daniel Rothman (PNAS 99:4167-4171) has also looked at the role of carbon dioxide within the last 500 million years and comes to the conclusion that global temperature and carbon dioxide content of the atmosphere simply do not correlate over geologic time. His is a direct comparison and I trust it more than the modeling mumbo-jumbo from Royer. Reliance on modeling is what brought us the sub-prime mortgage crisis and the economic downturn that followed. And thanks to modeling there are no more cod on the Grand Banks of Newfoundland. Orrin H. Pilkey and Linda Pilkey-Jarvis have written a book called "Useless Arithmetic" where they analyze numerous attempts to model the natural world and come to the conclusion that none of the models can be trusted to give quantitative results. At best they will give a qualitative idea and sometimes even that is not possible when one model says that sea level will increase and another says it will decrease due to water held in storage.Response: Firstly, thanks to Arno for emailing me Rothman 2002. What Rothman does is compare CO2 to climate over the past 500 million years and finds a number of periods where climate is cool and yet CO2 is at high levels. This question is examined in a later paper Royer 2006 which notes that the sun gets cooler as you go further back in time - solar output is around 5% lower 500 million years ago. When he compares the combined effect of solar and CO2 forcing, he finds good agreement. More on higher CO2 in the past... -
Vinny Burgoo at 14:09 PM on 3 February 2010It's not bad
Re Glacier Melt, Barnett 2005, Kehrwald 2008 and 'Severe consequences for one-sixth of world's population dependent on glacial melt for water supply': I wasn't going to bother with this tabulation any more (for reasons already given) but I can't let this slide. Barnett's 'one sixth of the world's population' refers to both snowmelt and icemelt - mostly the former, of course. Kehrwald's 'one sixth' is either a misattributed misrepresentation of Barnett or pure invention. Either way, it's gibberish. If you're genuinely interested in presenting a fair picture of the science, the least you can do is remove the Kehrwald reference and add something that highlights the importance of snowmelt to this alleged one sixth. Personally, I'd remove the whole thing. Barnett was based on a very dodgy analysis.Response: I notice Kehrwald 2008 cites the IPCC AR4 as their source so until I track down the IPCC's peer-reviewed source (most likely Barnett 2005), I've removed Kehrwald. I find it interesting that you'd 'remove the whole thing' - do you think the whole issue of threatened water resources for such a large proportion of the population is not worthy of concern? -
Marcus at 13:41 PM on 3 February 2010The role of stratospheric water vapor in global warming
What matters here is whether increasing SWV is a cause or an effect. The two most logical theories for the increase-increased convection & the oxidation of methane-both seem to be tied in with greenhouse gas emissions &/or the warming they produce. That hardly provides the basis for a "paradigm shift". -
Berényi Péter at 12:26 PM on 3 February 2010The role of stratospheric water vapor in global warming
chris, see my comment elsewhere: http://skepticalscience.com/Understanding-Trenberths-travesty.html#8093 The Solomon paper can also be an onset of a paradigm shift. -
Berényi Péter at 12:10 PM on 3 February 2010Understanding Trenberth's travesty
dough, it is also expedient to reconsider arbitrary data homogenization techniques used in retrospective "adjustment" of historical radiosonde temperature & humidity measurements. Just documented instrumentation changes should be used and only after experimental recalibration of the actual devices used. There are numerous abrupt downward shifts identified in the record. There is an extensive literature identifying them as artifacts. Having "corrected" the record by subtracting a step-function constructed this way, the overall downward trend vanishes. After the Solomon paper this practice is untenable. What if it's not just "natural variation" but the very way the climate system reconfigures itself to accommodate to increased CO2 levels? In a nonlinear system "feedback" can work in tricky ways. It can be positive on the "micro" level while occasional abrupt topological shifts can make the overall behavior well regulated within tight bounds, i.e. bring the state back to "normal". Let me clarify the idea through an example. Consider a pot of boiling water heated from below. As anyone knows, there are bubbles forming in the liquid and rising to the surface. Now, bubble formation is a tricky process, for each bubble should start tiny with a huge curvature on its outer surface, hence large negative surface tension. It throttles evaporation for a while, but as soon as the bubble gets bigger, this effect diminishes. We have a positive feedback. With very clean water free of "seeds" (like motes or air bubbles), it can get rather explosive. Just put clean water into the microwave, boil it for a while, let it cool, then re-boil. Don't use a bottle with a tight neck, it could actually blow up. And be prepared to clean up the mess. Anyway, in a normal pot of boiling water bubbles regularly end up on the surface and burst, releasing water vapor to the environment. It is a highly chaotic process, but the overall vapor contents of the pot is regulated, in spite of the positive feedback in bubble formation. Temperature is also constant with only slight local and temporal variations. One can see, the negative feedback works on a higher level and requires occasional reconfiguration of topology (bubble burst). If vapor contents of the pot were measured as a time series, then sudden drops associated with these topological changes removed from the record, one would fancy an ever increasing amount of steam in the pot. Putting some substance on the surface of water like oil would not make much difference. Of course it could "trap" steam for a while. Individual bubbles could get a little bit larger before bursting. But neither the temperature, nor the volume integrated steam contents of the pot would change. The dynamics of "water vapor feedback" to "carbon dioxide forcing" can be just like that. -
chris at 11:42 AM on 3 February 2010The role of stratospheric water vapor in global warming
re #41 Neither I suspect. One doesn't need to attempt to readdress and overhaul our understanding in response to every paper that comes out. The observation is that there have been short term changes in lower stratospheric water vapour, the causes of which are not known. It's not really known whether these changes can be considered forcings or are responses to changes in sea surface temperature or to aerosols, or what. The paper's only been out a few days, It will take some time to address its significance if any. It's worth restating that while the earth surface temperature hasn't warmed since 2005, it hasn't cooled since then either (a very short period for addressing "trends"!). However in the past 7 years the sun has progressed right to the bottom of a prolonged solar minimum, the secular solar irradiance trend has been a slight cooling one for a couple of decades, we're apparently in a cool ocean circulation regime, and now we have apparently had about a decade's worth of stratospheric water vapor "cooling" too. So one conclusion is that as this coincidence of cooling contributions that have oddly coincided during the last 7-10 years, dephases, that we're going to get quite a jump in surface temperature (rather like the analysis of Latif and Keenleyside in Nature the year before last): N. S. Keenlyside et al. (2008); Advancing decadal-scale climate prediction in the North Atlantic sector; Nature 453, 84-88 I think there's no question that we have got some "heat in the pipeline" at least from the solar cycle contribution. Otherwise this is about short term variability, and doesn't have much influence on our basic understanding of the earth surface temperature to rising greenhouse forcing... -
HumanityRules at 10:34 AM on 3 February 2010The role of stratospheric water vapor in global warming
Do we need to re-evaluate CO2s contribution to global warming from 1980 to present? If 30% less came from CO2 then you have to believe that even more heating is "in the pipeline" or reduce CO2s impact. Which one? -
Albatross at 10:19 AM on 3 February 2010Lessons from the Monckton/Plimer debate
This is my last post, hopefully for a while: " But no one is taking the crap he says at this dinner that seriously." Actually, they paid to see him, so they seem to be taking him very seriously IMO. I do not take Monckton seriously, my concern is that lay people will take him seriously and what the consequences will be for moving forward on this issue. "Skeptics" whom I debate almost always cite Monckton to substantiate their argument, so he does regrettably have some influence. McIntyre claims that "Everything that I've done in this, I've done in good faith". Yet, his actions and choice of language clearly fly in the face of that claim. Until last fall I might have agreed with you that McI has done some good; his actions and revelations since then have burnt that bridge. So forgive me if I have trouble assuming the best in the actions of McI and other 'skeptics'. You also need to remember that there are over 3000 climate scientists alone, yet you seem obsessed with the *alleged* transgressions of a handful of scientists. "I've heard Monckton make a pretty compelling argument for saving the trillions it would take to stop GW by reducing CO2, and instead using that money to adapt to future climate change, should it ever arrive" Actually, we are already witnessing the effects of AGW. Adaption is important, but this is not a choice, we have to do BOTH. Stern et al. have pointed out that reducing GHGs emissions is going to be costly, but not nearly as costly as dealing with the consequences down the road. Prevention is better than cure, and the same holds true for AGW. Regardless, adaption was a featured portion of AR4, WGII, see Chapters 17 and 18, so the IPCC and others are tackling that; Monckton is clearly not the only one to be thinking about adapting. Monckton is presenting a false choice. His argument fails to recognise that adaptation may be an option for the wealthy amongst us, but it is not really a viable option for people in Bangladesh. Those likely to experience the worst impacts from AGW are known to have the least resources to spend on adapting. And as I pointed out to you earlier, ocean acidification is going to be a significant problem down the road, regardless of what the climate sensitivity turns out to be. Finally, if we were to defer the cost of adaption to future generations we are not practicing inter-generational equity, because they will ultimately be burdened by the huge costs of adapting. That seems rather selfish and short-sighted to me. How about we spend a portion of those trillions on reducing GHGs and the remainder on adapting? Either way, just doing one is simply not going to cut it. -
sbarron2000 at 09:37 AM on 3 February 2010Lessons from the Monckton/Plimer debate
Just like those "unfortunate" CRU emails amongst friends and colleauges, you can't take what Monckton says to a dinner of 100 AGW skeptics too seriously. Albatross, you keep saying it's unfair that journalists, or Monckton, or I, treat your side unfairly. The CRU emails being taken out of context, never being intended for the public, or Jones having to deal with the pressure of FOI requests are great examples. But then you turn around and treat Monckton's speech to a room full of skeptics (that probably paid to see him) like he's testifying before congress. Monckton is playing to his audience. Much of what he says here are jokes at the establishment's expense. The crowd knows this, because it's fun to make fun of the other guy. But no one is taking the crap he says at this dinner that seriously. You shouldn't, either. And more importantly, if you're going to ask me to assume the best in the actions of Mann, Jones, CRU, et al, than the least you can do is do the same for WUWT, Monckton, McIntyre, etc. I've heard Monckton make a pretty compelling argument for saving the trillions it would take to stop GW by reducing CO2, and instead using that money to adapt to future climate change, should it ever arrive. That's an arugment that rings true to me, and its the kind of discussion I'd like to see more of. There has got to be more than one way to skin this AGW cat, doesn't there? -
Albatross at 08:00 AM on 3 February 2010Lessons from the Monckton/Plimer debate
SBarron, read what he is telling people and then try and argue that Monckton is enlightening us and fulfilling an important role in the science of AGW. http://www.theage.com.au/environment/climate-change/climate-sceptic-clouds-the-weather-issue-20100201-n8y3.html Sounds more like a conspiracy theorist to me.
Prev 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 Next