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Comments 117151 to 117200:
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Berényi Péter at 04:43 AM on 28 June 2010IPCC were wrong about Amazon rainforests
What are we talking about? Precipitation is hardly decreasing in Amazonia, at least not since 1920.
I have downloaded v2.prcp.Z from the GHCN v2 ftp server.
Then selected GHCN stations in Amazonia, in the rectangular region between 50°30'W - 74°30'W and 3°N - 13°S. This 24°×16° rectangle covers Amazonia pretty well (spherical distortion is negligible close to the equator).
There are 284 GHCN stations there, geographical distribution looks like this:
I have calculated average monthly precipitation for each 1°×1° cell where data were available. Then using these values average was obtained for 2°×2° cells, and so on up to 8°×8°. There are 6 such cells in the region, their average is the monthly signal for Amazonia. From this, one can get annual precipitation sums. I have chosen to sum up June-May data and assigned it to the starting year. This way I could use all the data available up to May 2010 (and didn't have to cut wet seasons in half).
The procedure followed is meant to compensate for possible uneven distribution of GHCN stations.
There is one caveat. In 1997 coverage of the region in GHCN started to deteriorate rapidly. Until 2003 stations are only getting sparse, but overall coverage is preserved more or less. After that even this is not enirely true.
To see the possible effect of gradual station dropout I show you the entire record between 1892-2009.
Data before 1920 are clearly unusable. If Amazonia would have been that dry, it must have been an epic event. The problem is station distribution prior to 1920 is not representative at all. People do not like too much rain, so they started to settle in drier parts of the region.
It is a bit better with recent station dropout, because it is not based on preferences of settlers, but on God-knows-what, probably unrelated to rain.
However, considering the central role GHCN plays in climate science and in all those expensive policy decisions based on it, the reckless way this database is handled is stunning.
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Doug Bostrom at 03:58 AM on 28 June 2010Accelerating ice loss from Antarctica and Greenland
Neat little example of a model confirmed by a robotic mission, both exploring Pine Island glacier in Antarctica and both tasked with helping to explain why this glacier has been on a speedy wasting trajectory in recent times. The discovery of an underwater mountain ridge could help solve the mystery of why Antarctica's Pine Island glacier is vanishing so rapidly. A robot submarine sent beneath the glacier's floating ice sheet has shown that there is a ridge rising 400 metres from the sea floor. Until recently, the glacier would have rested on this ridge, preventing warm seawater from reaching the ice and melting it from underneath. But the submarine has shown that the glacier no longer rests on the ridge - it has thinned and now floats above it (Nature Geoscience, DOI: 10.1038/ngeo890). ... In January, a modelling study suggested that if such a ridge did exist, then once the glacier retreated behind it, the glacier would not be able to recover. Ice shelf was kept intact by underwater ridge (New Scientist) -
David Grocott at 03:04 AM on 28 June 2010What causes the tropospheric hot spot?
I think it's important to note that in Nova's 'Skeptic's Handbook' she is clearly of the belief that the tropospheric hot spot is a signature specific to AGW; she refers to "the telltale “hot spot” warming pattern that greenhouse gases would leave". John, in his initial post, pointed out that this was incorrect, stating "we expect to see an amplified warming trend in the troposphere no matter what’s causing the warming". As a result of John's correction, Nova seems to have changed her position, and in her recent article in response to John's post wrote:...strictly any form of warming ought to increase evaporation, increase humidity, and in the world of climate models, raise the level of warming 10 km up over the tropics (ie, create a hot spot).
I think the fact that Nova has admitted her mistake on this is important. It's not just about semantics. If the hot spot was just a signature of AGW, then those arguing that it is absent would have an easier task. They could say, "yes there is warming, but the lack of a hot spot proves it is not humans". The fact that the hot spot acts as signature for warming from any source means that if people want to argue it is absent, they now have to say "no there is no warming, as demonstrated by the absence of the tropospheric hot spot". This would be a difficult argument to make considering all measurements show a warming trend. -
Doug Bostrom at 02:58 AM on 28 June 2010Abraham reply to Monckton
Another professor examines Monckton's work and finds it wanting. Detailed dissection here: The Monckton Files: Solar Variation
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Doug Bostrom at 02:38 AM on 28 June 2010What causes the tropospheric hot spot?
I read Nova's bit carefully and I note that she can produce a reasonable explanation of why a "hot spot" will exist, actually an explanation that worked well for me. She does not dispute that the phenomenon really must exist. Yet she refuses to acknowledge that failure to see the hotspot by instruments is a fundamental problem and that comparisons w/model predictions can't be made until the instrumentation issue is resolved. More rhetorical impressionism. I'm close to settling on the term "impressionist" for a fairly major swath of Nova-type persons. Prestidigitation is another possibility but it over-describes. -
Albatross at 02:21 AM on 28 June 2010What causes the tropospheric hot spot?
Robhon @13, I would like to echo your thoughts. The vitriol and invective in Ms. Nova's missive is both unacceptable and unprofessional, and only goes to undermine whatever credibility she thinks she might have on this issue. -
CBW at 02:20 AM on 28 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
D'oh, never mind my questions in #66. Neven's site has a link that shows some history. The answer is that it varies a lot year to year (big surprise in the arctic), and those yellow things are, indeed, buoys. Doug, I agree, it's amazing what cheap technology allows you to do. Have a look at the pictures in the link, above. Fascinating stuff. The only problem is that when it gets really interesting, the camera tends to die. -
Albatross at 02:18 AM on 28 June 2010What causes the tropospheric hot spot?
Ms. Nova continues be “mistakenly thinking the tropospheric hot spot is a signature of the greenhouse effect” There is so much wrong with her aggressive attack on this point. Is she denying that the greenhouse effect exists based on this misunderstanding? The greenhouse effect was around before we humans started emitting GHGs. That there is a “greenhouse effect” is very well established and not disputed, even by reasonable “skeptics”. Or is her misunderstanding of the science leading her to erroneously argue that we are not experiencing an enhanced greenhouse effect on account of higher concentrations of GHGs from human activities? Or is she concerned that the TROPICAL “hot spot” is not as strong as predicted by some models? The biosphere has been experiencing an enhanced greenhouse effect for decades now. How that manifests itself has been clearly documented by long term trends in multiple, independent observations. For example, long term warming in the SAT record, long term cooling of the lower stratosphere, long term increase in OHC (see Murphy et al. 2009 and others), and an increase in the height of the tropopause (Santer 2003) as evidenced by radiosonde data. IMO, Nova is being disingenuous with here musings on this topic and seems to be doing here best to obfuscate. That is evidenced by the lack of caveats in her musings as to the limitations of both the models and the observations—she seems to be naïve about the real-world complications of working with radiosonde (different sensors and platforms, sensor changes, sparse coverage etc.) data and MSU data. I also find it intriguing that she seems to claim to know more about this complex field than experts such as Santer et al. She should also read the README file for the UAH data sometime and see for herself the multitude of errors, corrections and other issues with that particular product. I take issue with the first graph that she presents in her latest post. First, the graph on the right panel is labeled “no hot spot” when in fact, there is warming, it is just not as significant as that predicted. The discrepancy between the models and the observations is complex. Partly b/c the maximum warming is predicted to occur near the tropopause, a region not sampled well by MSU products such as RSS b/c of “contamination” from the stratosphere—Ms. Nova does not seem to understand that the satellites do not directly measure temperature but radiances from relatively deep/coarse layers in the atmosphere-- a frustrating problem when one is trying to make measurements near regions of sharp temperature gradients such as between the troposphere and lower stratosphere (region where “hot spot” is expected to be a maximum. Not to mention the fact that the troposphere is warming while the lower stratosphere is cooling, so that further complicates trying to extract meaningful long-tern trends. The UW adjusted RSS product (which address the “contamination” issue) finds that, globally, the mid-troposphere has been warming of +0.15 K/decade since 1979 (from NCDC, annual temperatures up to and including 2009). On the model side, the AOGCMs do have issues with handling moist convection (i.e., thunderstorms), primarily because their horizontal grid spacing is too coarse. Consequently, they may be being too aggressive in their tropospheric warming over the tropics where convection predominates. IMHO, at most, this is a debate as to much to do with the limitations of the AOGCMs simulate convection and complex issues associated with accurately sampling and resolving temperature changes the upper-troposphere. The observed discrepancies have nothing whatsoever to do with whether or not the greenhouse effect is real, or whether or not we are experiencing an enhanced greenhouse effect. There are more appropriate and reliable measures which support the existence of an enhanced greenhouse effect. As far as I can tell, Ms. Nova’s beloved “missing hot spot” also has nothing to do with global equilibrium climate sensitivity. -
Doug Bostrom at 02:14 AM on 28 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
How amazing and marvelous that we're able to drop remote sensing equipment like that at the N. Pole. Little chance of theft, either. Years ago I was involved with a project to attach radio-equipped digital imagers to outdoor analog instruments, reporting to data concentrator boxes. One of our camera gizmos was stolen but managed to send a final picture before going out of range, showing the interior of a pickup truck bed. No mug shot of the perp, unfortunately. -
Rob Honeycutt at 02:12 AM on 28 June 2010What causes the tropospheric hot spot?
I have to say to John, bravo for keeping above the fray. Again, reading the tone of both the article and the discussion on JoNova's site is rather alarming. It really does little to address the scientific issues regarding climate change when people stoop to such personal attacks. I'd like to better understand why Nova and her cohorts reject this stuff and where they're getting their information. I honestly would. But I stop reading when it gets personal. I also have to thank those who post on this site with their perspectives that reject AGW for maintaining a sense of decorum. It makes a huge difference. I'm sure you often feel outnumbered here but I hope that you feel you get a fair hearing. If you ask me, that is what skepticism is all about. A fair hearing from all sides. -
carrot eater at 02:06 AM on 28 June 2010What causes the tropospheric hot spot?
RickG: It ends up being a negative feedback, in a way that is perhaps not obvious. For the greenhouse effect to work, there has to be a lapse rate. The emission that makes it back out to space needs to be from a colder place than the surface. But due to this 'hot spot' effect, the lapse rate is reduced. So the greenhouse effect becomes less powerful than it otherwise would have been. But there's also a positive feedback in the story, as the increased atmospheric moisture that causes the 'hot spot' itself causes a major positive feedback, as water vapor is a greenhouse gas. So in short: the "hot spot" is caused by something that is a positive feedback, but it itself causes a negative feedback. Hope that wasn't muddled. -
carrot eater at 02:00 AM on 28 June 2010What causes the tropospheric hot spot?
Thank you, for this is much, much improved on the previous post. I'll note that while it's difficult to nail down this long-term trend in the observations, the short term behavior is possibly consistent with theory. After all, the satellite records show amplified variability in the troposphere with El Ninos and La Ninas. I think this observation may be related to the same mechanism, just over the short term. -
CBW at 01:58 AM on 28 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
Neven #25, those are pretty pictures of the pole. (Neven has links on his site to the two cameras. Check them a couple of times a day to see the changing skies (and melting ice.)) Does anyone know if this is a common occurrence at the pole, and does it usually happen this early in the summer? Are those yellow things buoys? -
CBW at 01:41 AM on 28 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
gallopingcamel, #63, why would anyone be "panic stricken" about the eventual melting of arctic sea ice when it is simply another consequence of a process we've been witnessing for twenty years or more? And why does it "impress" you that we're not panic stricken? You appear to be insulting us with a backhanded compliment embedded in an "apology." And, for the record, the north pole doesn't have an "ice sheet." An ice sheet exists on land. The north pole has sea ice. -
Peter Hogarth at 01:32 AM on 28 June 2010Sea level rise is exaggerated
neilperth at 14:02 PM on 7 October, 2009 Forgive the late entry here, not wishing to push my own efforts, but many of the sea level rise issues were also discussed here recently. I suggest you read the up to date references and review articles as I took some time assembling them (and have gained few more since). A lot has happened in the past ten years, for example routine precision vertical reference station values from GPS and greatly improved estimates of isostatic rebound and crustal movements, as well as better and more satellite data from several satellites. With reference to your comments about the IPCC, to see what the sea level measuring community is currently saying look at the GLOSS documents and please, read the references. daniel at 22:03 PM on 26 June, 2010 References to the any recent "downturn" in sea level rise are already out of date. The charts above have been updated with latest satellite data including JASON2 and Envisat, see link above. -
Doug Bostrom at 00:46 AM on 28 June 2010Sea level rise is exaggerated
"Look in the mirror?" Calm down, Daniel, remember I'm neither the author of the paper nor the person doing a casual critique of methods without resort to quantitative treatment such as that done by the authors being critiqued. Do the work in detail necessary to show the paper's statistical treatment is undependable and don't imagine that sarcastic remarks are a useful substitute. -
Paul D at 00:46 AM on 28 June 2010What causes the tropospheric hot spot?
In a previous post I suggested a categorisation of signatures and fingerprints. This one appears to fall into the same category as the C13/C12 ratio. A secondary signature. Your first line of proof/defence should be robust primary signatures, backed up by supporting secondary signatures? -
daniel at 00:31 AM on 28 June 2010Sea level rise is exaggerated
Doug, it's simple, look at the graph. A claim of a linear trend is made with 10 data points of clearly very high uncertainties. The recent trend which is of much shorter length in time but of higher resolution and certainty is then tacked on the end and the claim is made that a recent rapid rise in sea level is observed. Any bachelor degree graduate can see that it is not a valid conclusion from the data. The error estimates give us the level of uncertainty, the boundaries within which the true paleo-sea level may reside at a given level of statistical confidence. Do you belive it is valid to say that the sea level did not deviate significantly from the proposed linear trend during this period? It's not my credibility that's at stake here doug, look in the mirror. -
RickG at 00:12 AM on 28 June 2010Astronomical cycles
Looking back at the 100% AGW 1970-2000 IPCC claim, I noticed a discrepancy. On page 1 he states "practically" 100%, but on pages 9 & 13 he leaves the word "practically" out. Isn't that something the reviewers should catch? -
Peter Hogarth at 00:05 AM on 28 June 2010What causes the tropospheric hot spot?
To add further information to Johns explanation, there is also another paper on this topic by Santer 2008, and a highly accessible fact sheet that goes with it. Santer also covers some aspects of this debate (and others) in his May 2010 Testimony for House Select Committee on Energy Independence and Global Warming. He concludes that the discrepancy between modeling and observations has largely been resolved. The expanding nature of our knowledge of both natural climate change processes in the tropics and of the complexity of effects of anthropogenic forcing and warming on these processes is further illustrated in Sherwood 2010 on the effects of tropospheric humidity changes and polewards shifts of atmospheric zones; Seidel 2007 on observed and modeled widening of the tropical belt, and in Chou 2010 on observed and modeled weakening of the tropical atmospheric circulation. All of these and many more strands of emerging evidence add to the robust global climate trends which are already generally accepted and appear consistent with global warming associated with a major CO2 forcing component. -
TOP at 23:56 PM on 27 June 2010What causes the tropospheric hot spot?
J. Neuman, 1955 for an explanation of lapse rate change with latitude and season. J.G. Moore, 1956 Distinction between upper and lower troposphere trends. I. Thaler et al, 2010 Discussion of current models and recent satellite data. Trend is highly dependent on scenario chosen. -
Riccardo at 23:51 PM on 27 June 2010What causes the tropospheric hot spot?
RickG, if anything, it should be considered as a negative feedback. Indeed it's some forcing that causes the response of a reduced lapse rate which, in turn, increases OLR emission. Note that the opposite is true at mid and high latitudes. -
Doug Bostrom at 23:44 PM on 27 June 2010IPCC were wrong about Amazon rainforests
Oops, meant to say WG1 &WG2. WG3 is where things become really debatable. -
Doug Bostrom at 23:39 PM on 27 June 2010IPCC were wrong about Amazon rainforests
I should amend my earlier remarks to Willis. Willis, the reason I'm probably coming off as a bemused-to-irritated on this is for the very reason that you're clearly capable of spending your effort on more useful activities that dragging up done-to-death issues such as this one. On WUWT you've performed some noteworthy service and in fact have stuck your neck out to help set some of the more resistant folks there straight on some science basics. You've corrected the record on C02 attribution, you've assisted WUWT readers in understanding that there is in fact a phenomenon called anthropogenic warming, you've traced the path of anthropogenic pH change in the ocean. You've taken a bit of flack for that, no surprise. Despite all your unusually pragmatic work at WUWT, here you are regressed to grinding on IPCC process minutia of no actual significance. I don't understand it, it does not seem in character and when I read your post to Riccardo here I honestly wondered, "is this really Willis Eschenbach?" Maybe your effort at WUWT is about getting folks to understand they should now be touting adaptation but I don't really know, only you can say. What I can say with more confidence is that focusing on one miss out of thousands of accurate hits is to miss a major point, namely that the IPCC WG1 synthesis is overwhelmingly useful in bringing together a multitude of inputs to help understand a novel situation we've accidentally created on our planet. If adaptation is the new mode for people discomfited with the unfortunate facts we're creating on the ground, maybe it would be better to focus on sections of the synthesis other than WG1. The more into policy one goes the more there is to argue about, meanwhile the fundamental science portion is a pretty futile subject of discussion at this point, as you've been pointing out. -
RickG at 23:35 PM on 27 June 2010What causes the tropospheric hot spot?
Thanks David, I was thinking possibly a feedback if anything, but "neither" makes sense. If I understand, correctly its a result rather than a mechanism. -
David Grocott at 23:05 PM on 27 June 2010What causes the tropospheric hot spot?
RickG, Neither, it is simply a signature which the models says should be seen if the earth is warming sufficiently. -
Doug Bostrom at 22:36 PM on 27 June 2010IPCC were wrong about Amazon rainforests
...is the reason that this website is trying so hard to make folks think that the IPCC is blameless in this matter. More unfounded speculations, daubs of paint flung on a canvas to make an impression. What, are you not only a rhetorical artiste but telepathic? A mind-reader? Meanwhile, back in reality, aren't you becoming just a wee bit self-conscious about what a strange impression you convey when you're so obsessed with the image you're trying to portray here, and what odd little bits of arcana you're trumpeting as some sort of triumphant evidence of defect? Bottom line is that the IPCC has justifiable and clearly stated policies about what sort of expertise and publications quality they draw on to construct synthesis reports. Out of many thousands of such dependencies they have apparently flubbed less than a handful. In the case of the error here it was completely immaterial because it had no actual effect on the conclusion and the reason you must bring it up is because there's only known material error, the Himalaya matter, which you can discuss elsewhere here if you're rooted in the past. As I say Willis, you're definitely capable of better work than this and you ought not to waste your time on lunatic-fringe arcana. Finally, whether the IPCC relies on un-referenced puff pieces from the WWF is hardly "trivia" as you say ... It is -so- strange that you're so desperate to leave a final note in the air here that you'd keep repeating this. One more time, hopefully, unless you're absolutely intractable: Original author of the Amazon study in question, Nepstad: In sum, the IPCC statement on the Amazon was correct. The report that is cited in support of the IPCC statement (Rowell and Moore 2000) omitted some citations in support of the 40% value statement. -
Spencer Weart at 22:19 PM on 27 June 2010What causes the tropospheric hot spot?
According to Santer et al. (2008), International Journal of Climatology 28: 1703-22 [doi:10.1002/joc.1756], "there is no longer a serious discrepancy between modelled and observed trends in tropical lapse rates. This emerging reconciliation of models and observations has two primary explanations. First, because of changes in the treatment of buoy and satellite information, new surface temperature datasets yield slightly reduced tropical warming relative to earlier versions. Second, recently developed satellite and radiosonde datasets show larger warming of the tropical lower troposphere. In the case of a new satellite dataset from Remote Sensing Systems (RSS), enhanced warming is due to an improved procedure of adjusting for inter-satellite biases." -
RickG at 22:11 PM on 27 June 2010What causes the tropospheric hot spot?
Question. Would the "hot spot" be considered a forcing or feedback? -
David Grocott at 21:01 PM on 27 June 2010What causes the tropospheric hot spot?
Re: this sentence:The reason the hot spot in box c is so strong is because greenhouse warming is so strong compared to the other forcings.
I would say "...is because greenhouse warming has been so strong compared to other forcings over the last 100 years" as that is all the figure is showing. Non-CO2 forcings have been small, so the tropospheric response has been small. Perhaps someone could answer this for me: to pose a hypothetical question - if the current warming turns out to have been caused by changes in solar output would we expect to see an identical tropospheric hot spot? Presumably we would, as it's the amount of warming, not the type, that determines the existence of the hot spot, right? -
CBDunkerson at 20:40 PM on 27 June 2010Temp record is unreliable
BP #62, if what you say were true then would not the satellite and surface temperature results diverge more and more as time goes by? After all, your argument is essentially that the satellite temperature data was 'set' to conform to surface results (though in fact UAH originally came up with results significantly different from the surface results and only later came to line up after several errors were identified). However, now that those 'assumptions' needed to match the satellite record up are in place they are fixed. If the surface temperature continued to change, per the 'UHI error theory' for instance, then it should diverge from the satellite record which is still based on the assumptions needed to match up to the older temperatures. Yet we aren't seeing this sort of growing divergence. I believe that is because you are simply incorrect about the satellite record being deliberately 'set equal' to the surface record... as also demonstrated by the fact that they originally did not match and the primary adjustments made since then have had to do with correcting for sensor drift rather than baselining to the surface data. -
Riccardo at 20:32 PM on 27 June 2010IPCC were wrong about Amazon rainforests
By the way, the IPCC procedure does not exclude the use of non peer-reviewed papers. Though, I agree thet it's not a good choice to use them, in particular when the proper peer reviewed papers are available. Definitely it should be avoided. But I'm way more interested in the science (the substance) than in the formal procedures, and the former looks correct and supported by proper scientific papers. -
Phil at 20:02 PM on 27 June 2010What causes the tropospheric hot spot?
Just a typo, John. I think 3 paras up from the bottom; last sentence - the word "equivocally" should be "unequivocally"Response: Fixed, thanks for the tip. Dang semantic glitches. -
Riccardo at 20:01 PM on 27 June 2010IPCC were wrong about Amazon rainforests
If we care about the form more than the substance, we should also check the ortography in the IPCC reports. After all, if one cannot write in good english how could he ever claim to know the science? -
Willis Eschenbach at 19:56 PM on 27 June 2010IPCC were wrong about Amazon rainforests
doug_bostrom at 17:16 PM on 27 June, 2010 I had said:... Now, it's possible they were relying on the 1994 document (although we have only this website's word for it). But I find nothing in that document that makes the 40% claim either ... perhaps someone could quote where in the 1994 document the 40% claim was made.
You replied:Original author of the Amazon study in question Nepstad:
In other words, you can't find anything in the 1994 document that supports the 40% claim ... and neither can Nepstad. He gives no citation, he only repeats the claim that it was correct, and says that Rowell and Moore "omitted some citations". Well ... yes. It is those "omitted citations", that neither you nor Nepstad have provided, that I am asking for. Where did the "40%" claim come from? Nepstad says that the WWF authorsIn sum, the IPCC statement on the Amazon was correct. The report that is cited in support of the IPCC statement (Rowell and Moore 2000) omitted some citations in support of the 40% value statement.
So it's your impressionism versus the ultimate authority on the matter, the fellow who actually did the research to which the citation trail was supposed to lead, in other words reality.... had originally cited the IPAM website where the statement was made that 30 to 40% of the forests of the Amazon were susceptible to small changes in rainfall.
Again, this sounds good. But my search of the IPAM website doesn't reveal any citations to the 40% figure there either. So where did it come from? Finally, whether the IPCC relies on un-referenced puff pieces from the WWF is hardly "trivia" as you say ... it goes directly to their claims of scientific credibility, and is the reason that this website is trying so hard to make folks think that the IPCC is blameless in this matter. -
Doug Bostrom at 17:16 PM on 27 June 2010IPCC were wrong about Amazon rainforests
Willis, the problem here is that you're so keen on your impressionist artwork, you're painting a picture that does not resemble reality. Your claim: Now, it's possible they were relying on the 1994 document (although we have only this website's word for it). But I find nothing in that document that makes the 40% claim either ... perhaps someone could quote where in the 1994 document the 40% claim was made. Original author of the Amazon study in question Nepstad: In sum, the IPCC statement on the Amazon was correct. The report that is cited in support of the IPCC statement (Rowell and Moore 2000) omitted some citations in support of the 40% value statement. So it's your impressionism versus the ultimate authority on the matter, the fellow who actually did the research to which the citation trail was supposed to lead, in other words reality. As I say, you're resurrecting this trivia because it's useful rhetoric, if nobody bothers to correct you. I've read some of your stuff on WUWT, you're capable of producing much original and entertaining pieces so it's baffling that you'd resort to such a stale technique. -
Willis Eschenbach at 17:01 PM on 27 June 2010IPCC were wrong about Amazon rainforests
doug_bostrom at 10:24 AM on 27 June, 2010Resurrecting "Amazongate?"
Nope. I bring it up to show that the IPCC did not follow its own guidelines, and that there was nothing at the end of the citation trail that supported the 40% number.Now, I am not saying that the claim is wrong. I do not know whether it is or not.
But you'll bring it up because it's handy rhetoric. -
ScaredAmoeba at 16:50 PM on 27 June 2010Astronomical cycles
There appears to be an 'Article in Press' version of the Scafetta paper over at SPPI The fact that SPPI [of Monckton infamy] received what was probably an embargoed pre-publication copy could easily lead one to draw all manner of conclusions about the motives behind this. Scafetta has produced [ahem]poorweak papers in the past and I suspect this attempt is just more of the same. -
gallopingcamel at 14:15 PM on 27 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
Oops! I meant #62! -
gallopingcamel at 14:14 PM on 27 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
John Cook, My apologies for getting "Off Topic" in #69. I am impressed by the fact that nobody on this blog is panic stricken by the prospect that north pole ice sheet may be smaller in September 2010 than it was in 2007. -
Lon Hocker at 11:47 AM on 27 June 2010Is the long-term trend in CO2 caused by warming of the oceans?
Oops, should have been "increases the uptake" instead of "reduces the uptake" -
Lon Hocker at 11:45 AM on 27 June 2010Is the long-term trend in CO2 caused by warming of the oceans?
Peter: Thank you for the excellent comment. I agree with pretty much everything you wrote. The carbon ratios support the emission of CO2 from the equator and absorption near the poles with a half time of about 5 years, regardless of model, as long as you accept the 100GtC flow. No question that there is a net flow of CO2 into the ocean from anthropological sources. The higher atmospheric CO2 due to anthropogenic sources reduces the amount that would have been emitted by the ocean for the same temperature increase (and decreases the uptake), and that would have been a clearer description than my stating that it came from the oceans. With a 5-year tome constant, the anthropogenic contributions to the CO2 increase would be about 25% of the observed increase, leaving the rest for the temperature change. I realize that this is an emotional subject for all, and I likely would have been more politic to not have written such a aggressive headline! In any event the science is far from settled, and I wanted to present a contrasting argument to that usually accepted. I greatly value postings, such as yours, that provide information and opinion dispassionately . I know that my understanding of this is far from complete, and I am open to changing my mind on pretty much everything, except for the Mauna Loa and satellite data, and my understanding of math and calculus! Again, thank you, and I would enjoy hearing more of your perspectives. -
Berényi Péter at 11:03 AM on 27 June 2010Temp record is unreliable
#61 Ned at 00:20 AM on 5 April, 2010 The close agreement between satellite and surface temperatures is a bit of a problem for those skeptics who believe that the surface record is hopelessly contaminated by UHI effect Ned, the problem with satellite "temperatures" is that satellites do not measure temperature, not even color temperature, but for a specific layer of atmosphere (e.g. lower troposphere) brightness temperature is measured in a single narrow IR band. This measurement may be accurate and precise, but it is insufficient in itself to recover proper atmospheric temperatures. In order to make that transition, you need an atmospheric model. With the model atmosphere you can calculate the brightness temperature backwards and tune parameters until a match is accomplished with satellite brightness temperature data. Then you can look at the lower troposphere temperature of the model and call it temperature. However, with no further assumptions, the relation is not reversible, i.e. many different atmospheric states lend the same brightness temperature as seen from above. The very assumptions in the model, that make reverse calculations possible are the hidden backlink to surface temperature data. For there is no other way to verify model reliability than compare it to actual in situ measurements. Therefore if the surface temperature record is unreliable, so are atmospheric models used to transform satellite measured brightness temperatures to atmospheric temperatures. That makes the whole satellite thing dependent on surface data, in spite of independent sensor calibration methods. -
Doug Bostrom at 10:24 AM on 27 June 2010IPCC were wrong about Amazon rainforests
Resurrecting "Amazongate?" Now, I am not saying that the claim is wrong. I do not know whether it is or not. But you'll bring it up because it's handy rhetoric. IPCC has something like a "four nines" reliability record with cites, so dredging up this silliness is only going to continue playing badly for those using it for impressionist art purposes. Read what Nepstad himself had to say. Senior Scientist Daniel Nepstad endorses the correctness of the IPCC’s (AR4) statement on Amazon forest susceptibility to rainfall reduction: "The IPCC statement on the Amazon is correct, but the citations listed in the Rowell and Moore report were incomplete. (The authors of this report interviewed several researchers, including the author of this note, and had originally cited the IPAM website where the statement was made that 30 to 40% of the forests of the Amazon were susceptible to small changes in rainfall). Our 1999 article (Nepstad et al. 1999) estimated that 630,000 km2 of forests were severely drought stressed in 1998, as Rowell and Moore correctly state, but this forest area is only 15% of the total area of forest in the Brazilian Amazon. In another article published in Nature, in 1994, we used less conservative assumptions to estimate that approximately half of the forests of the Amazon depleted large portions of their available soil moisture during seasonal or episodic drought (Nepstad et al. 1994). After the Rowell and Moore report was released in 2000, and prior to the publication of the IPCC AR4, new evidence of the full extent of severe drought in the Amazon was available. In 2004, we estimated that half of the forest area of the Amazon Basin had either fallen below, or was very close to, the critical level of soil moisture below which trees begin to die in 1998. This estimate incorporated new rainfall data and results from an experimental reduction of rainfall in an Amazon forest that we had conducted with funding from the US National Science Foundation (Nepstad et al. 2004). Field evidence of the soil moisture critical threshold is presented in Nepstad et al. 2007. In sum, the IPCC statement on the Amazon was correct. The report that is cited in support of the IPCC statement (Rowell and Moore 2000) omitted some citations in support of the 40% value statement. -
Willis Eschenbach at 09:38 AM on 27 June 2010IPCC were wrong about Amazon rainforests
Riccardo, thanks for the links. The WWF document cites the Nature document (Nepstad 1999) as their source for the statement that"Up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation".
I don't find that. The nearest I could find is a quote in the 1994 paper that supports the statement referred to in the head post:"A 1994 paper estimated that around half of the Amazonian forests lost large portions of their available soil moisture during drought."
Yes, forests lose soil moisture during a drought. That is a very different statement from saying that the Amazon could "react drastically to even a slight reduction in precipitation." In fact, the 1994 paper says that in 2001, half of the Amazon suffered a 50% loss in soil water ... but it says nothing about that causing a "drastic reaction". I find nothing in the cited document that makes the 40% claim. This website says that the WWF citation is incorrect, that they really were relying on a 1994 document, Nepstad 1994. It is unknown how this website came to that conclusion ... but the practice of randomly substituting one citation for another hardly inspires confidence. Now, it's possible they were relying on the 1994 document (although we have only this website's word for it). But I find nothing in that document that makes the 40% claim either ... perhaps someone could quote where in the 1994 document the 40% claim was made. Now, I am not saying that the claim is wrong. I do not know whether it is or not. I do think, however, that for the IPCC to rely on a WWF document whose cited reference for a claim does not support what the WWF document says is ... well, it is far away from Pachauri's claim that the IPCC depends 100% on peer reviewed science. This is not even second-hand peer reviewed science, the citation doesn't support the claim. And for this website to say that the WWF document is really referring to a totally different paper (and one which does not contain the 40% claim either) is Monday morning quarterbacking. You present no evidence at all that the WWF was referring to the 1994 paper. Now that you know that the 1994 paper does not contain anything even remotely similar to the claim that "Up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation", I suppose that you could come up with some other citation that kinda supports the claim if you squint at it in the right way ... but that's not the point. The point is that the IPCC relied on a WWF paper which was not peer-reviewed, and the citation listed for that WWF claim did not back up the claim ... Finally, you say:However, the 40% figure comes from several other papers by the same author that the WWF failed to cite. ... In 2004, new rainfall data showed that half of the forest area of the Amazon Basin had either fallen below, or was very close to, the critical level of soil moisture below which trees begin to die (Nepstad 2004).
Sorry, not possible. The WWF paper is not dated, but the most recent citation is from 2000, and it refers to 2001 as "the future", viz:So when will the next El Niño occur? Scientists at the American Climate Prediction Centre believe that La Niña conditions will prevail globally until March 2000 and it is too early to say when the next El Niño will be. However, the Eighth ASEAN Ministerial meeting on Haze in August concluded that as “La Niña is expected to weaken by the end of this year, meteorological experts have predicted a likely recurrence of dry conditions associated with the El Niño phenomenon next year or by 2001”.
So unless WWF has invented time travel, the idea that the WWF "failed to cite" a 2004 document is simply not possible ... -
Riccardo at 07:58 AM on 27 June 2010IPCC were wrong about Amazon rainforests
For the lazy readers, here's the Global Review of Forrest Fires, Nepstad 2004, Nepstad 2007 and Philips 2009. And should the webmaster at WHRC decide to move their pages again, we won't let them hide anything: Nepstad, D., P. Lefebvre, U. Lopes da Silva, J. Tomasella, P. Schlesinger, L. Solórzano, P. Moutinho, D. Ray, and J. Guerreira Benito. 2004. Amazon drought and its implications for forest flammability and tree growth: a basin-wide analysis. Global Change Biology 10(5):704-717. Nepstad, D.C., I.M. Tohver, D. Ray, P. Moutinho, and G. Cardinot. 2007. Mortality of large trees and lianas following experimental drought in an Amazon Forest. Ecology 88(9):2259-2269. John, you might want to update your link and delete this comment. -
gallopingcamel at 07:53 AM on 27 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
CBDunkerson (#54), No big deal. When one is looking at the poles satellite data would be more convincing. Somewhere on another thread it was shown that there are only a handful of high latitude ground stations in the NASA and NOAA data bases. Perhaps you or Berenyi Peter can say how many ground stations there are above 66 degrees latitude. I suspect that the number is too small to justify the fine grained contours seen on NASA anomaly maps.Moderator Response: There's no specific thread (yet) for discussion of polar temperature measurement and interpolation so for the time being please continue discussing the polar instrumental temperature record on the Temperature Record Is Unreliable thread. Thanks! -
Doug Bostrom at 07:03 AM on 27 June 2010IPCC were wrong about Amazon rainforests
Welcome to Skeptical Science, Willis. Do you have anything more substantial to offer other than pointing out expired links? -
Willis Eschenbach at 07:00 AM on 27 June 2010IPCC were wrong about Amazon rainforests
Two of your links go nowhere. The third says nothing about "up to 40% of the Brazilian forest". How is this supposed to convince anyone? -
J Bowers at 06:56 AM on 27 June 2010How Jo Nova doesn't get past climate change
To complement this post, I highly recommend Prof. David Greenwood's comment at Climatesight, which is a very lucid description of what we know. http://climatesight.org/the-credibility-spectrum/#comment-2320 Jo Nova should it read it, too, especially as David Greenwood started out as a sceptic.
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