Arguments
Recent Comments
Prev 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 Next
Comments 124801 to 124850:
-
Peer reviewed impacts of global warming
Riccardo, Thanks for the link. Fascinating reading and shows how complex it all is at the micro level. I'll read up again on the earth tilt stuff in my reference book of choice - 'A Rough Guide to Climate Science' -
Doug Bostrom at 12:34 PM on 31 January 2010On the reliability of the U.S. Surface Temperature Record
Tom Dayton at 11:41 AM on 31 January, 2010 "A second post on D'Aleo and Watts from the Texas State Climatologist. " Pretty clear why he's got his post. Ability plus communications skills in abundance. That was very interesting, thank you. -
Tom Dayton at 11:41 AM on 31 January 2010On the reliability of the U.S. Surface Temperature Record
A second post on D'Aleo and Watts from the Texas State Climatologist. -
Marcus at 11:40 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Here's one point I've been wanting to raise. If Monckton & the ACRIM model for TSI is correct (i.e. rising TSI over the last 30 years), then where is the corresponding Stratospheric warming? Even with the "intervention" of several major volcanic eruptions in the 1990's, stratospheric temperatures have still been trending *downward*. Like rising tropospheric temperatures, this stratospheric cooling is consistent with the Greenhouse Gas theory of recent climate change. Odd, then, how observed trends/phenomena seem to support, & reinforce, AGW theory-whilst we're still waiting for any evidence that supports the "theories" of Plimer, Monckton et al. -
Albatross at 11:32 AM on 31 January 2010Lessons from the Monckton/Plimer debate
EdB, and before you think that Wegman was *impartial* and credible, go over to Deepclimate.org and do some reading there.Response: Keep in mind that those pages on Deep Climate will disappear into the archives long after people will read your comment - it's always recommended to post direct links to the relevant pages. Eg: Very interesting posts and the discussion comments are also worth a read, particularly one of the principals in the analysis drops by and presents their views in a surprisingly forceful fashion. -
chris at 11:30 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Well yes, but you're making three illogic arguments Peter. (i) Upper tropospheric water vapour concentrations aren't simply a consequence of lightning-associated atmospheric convection. These processes promote the transport of water to the high troposphere, but it's the upper tropospheric temperature that dominates the equilibrium UTWV concentrations. That's what Price and Asfur show in their 2006 paper (see link in my post just above). Spikes in UTWV follow lightning with a lag on the timescale of around a day (as determined by correlating lightning activity with independent determination of UTWV) and drop again; according to Price and Asfur this may account for very short term variability but doesn't dominate the globally-averaged temperature-dependent levels of UTWV. In other words UTWV can rise without an increase in lightning (or lightning-associated increased convective water vapour transport). (ii) The Schumann resonance method is very nice, and Price and Asfur propose this as a means of assessing daily variability of regional upper tropospheric water vapour, although their paper (Price and Asfur, 2006) has some caveats about its applicability. But it's illogic to assert that the Schumann resonance must increase in order for the water vapour feedback to be validated. That's a non-sequitur (see (i)). Lightning is expected to increase somewhat in a warming world, and Pinto and Pinto have observed this in their analysis over Brazil, but this issue certainly isn't settled. Pinto and Pinto, and Price and Asfur discuss the uncertainties in their papers; you haven't given us insight into the source of your certainty..It certainly can't arise from the work of the scientists that you cite. (iii) On this thread and the last one on tropospheric water vapour, you are taking some rather tenuous analyses, analyses that the scientists themselves are completely upfront about the uncertainties and their potentially premature nature....and ignoring all of this. Neither the Pinto's not Price and Asfur consider that their analyses are incompatible with expectations from physics and models (the Pinto's consider that their data are consistent with expectations from models). Price and Asfur don't consider that their analysis (Schumann resonance and all) has very much at all to say about the response of UTWV in a warming world, 'though they do consider that they might be able to get a handle on UTWV variability on a daily time scale. The bottom line is that it is possible ('though not completely straightforward!) to determine tropospheric water vapour levels using satellites. These data are consistent with expectations (water vapour rises as the upper troposphere warms). Likewise, despite the considerable problems with radiosondes, reanalysis of the radiosonde water vapour record doesn't give any reason to discount the interpretations from satellite data and models. One should consider all the evidence, uncertainties and all, before attempting grand conclusions. -
Albatross at 11:17 AM on 31 January 2010Lessons from the Monckton/Plimer debate
@56. I do not follow your logic concerning the increase of temperature and lightning and computer models. The reality is that, globally, the planet warmed by almost 1 C in the past 130 years or so. Using your flawed logic (which seems to be based on results of a paper by Pinto and Pinto) there should have been a 30-40% increase in lightning flashes across the globe in response to the 1 C warming--maybe there has been, we just do not have a long enough data record to say so-- we do not have 130 years of reliable global lightning data. Anyhow, just b/c recent trends in global Schumann resonance has allegedly shown no long term increases in recent decades (no citation provided) we are meant to conclude that 1) The warming has not happened, and 2) This somehow means the AGCMS are all wrong. There are many other reliable metrics that all point to the planet having warmed, and lightning is not necessarily the best suited for that purpose for reasons I provided earlier on this thread. As for your claim that AGCMs suggest that lightning activity will increase, you seem to be incorrectly referring to the work of Price and Rind (1994, JGR), their model simulations indicated a 30% increase in global lightning for a DOUBLING of CO2-- not a 1 C increase in temperature as you suggest. Also, we are a long ways off doubling CO2. I could not find the Pinto and Pinto paper to which you are referring (correct citation please); most of their other work seems to have been done over small study areas in Brazil. Crook (1996, Monthly Weather Review) investigated the impacts of small changes of moisture and temperature the PBL on convective initiation (CI) and t'storm intensity. CI is much more complex than you seem to think. Did you read my earlier post? Warming over the Sahara is not going to produce thunderstorms unless there is sufficient low-level moisture, that is the limiting factor there, not temperature. Warming alone is not a sufficient condition to trigger a thunderstorm. There are other complicating factors, such as the fact that the entire troposphere is warming, and this affects the amount of CAPE and laspe rates (e.g., Del Genio 2007, GRL). Also, wind shear regimes are changing as the planet warms and this affects the longevity of the thunderstorms. The ad hoc adjustments to which you are referring are no such thing. If you are referring to the ARGO floats, then there was a very good reason for the adjustments, a faulty sensor. The nature of the error is known and has been quantified and has been corrected for accordingly. I'm sorry, this is not the "aha, got you" moment that you were hoping for. There have been many, many people who have claimed to have found the nail in the coffin of AGW, and none of them have succeeded yet. PS: Reeve and Toumi (2007; QJRMS) conclude that: "Data from the Optical Transient Detector lightning sensor are analysed to investigate the hypothesis that global lightning activity will increase should the average global temperature increase. It is shown that changes in global monthly land lightning activity are well correlated with changes in global monthly land wet-bulb temperatures. the correlation is strongest in the northern hemisphere and weak in the southern hemisphere. the conclusion is that a high land-area to sea-area ratio is necessary for a good correlation. Contrary to expectation, the tropics show no correlation. the results predict that a change in the average land wet-bulb temperature of the globe of just 1K would result in a change in lightning activity of about 40%." Also: Watkins et al. (1998; GRL) found a weak linear increase in global lightning activity between 1971 and 1996, and attributed that increase to more lighting over S. America. -
shawnhet at 11:10 AM on 31 January 2010Lessons from the Monckton/Plimer debate
For the record, there is not necessarily any conflict with suggesting that climate is insensitive and that natural variations are(primarily) responsible for the climate change or whatever. It simply requires that the (effective) value of the natural forcings be higher than the consensus estimates. While you would have to ask each man the specifics of their position, to assume that because they argue these positions, they contradict one another does not follow. Cheers, :) -
Berényi Péter at 10:39 AM on 31 January 2010Lessons from the Monckton/Plimer debate
chris, it is not lightning that transfers water vapor to upper troposphere, but deep convection. Which also works as an electrostatic generator, hence the lightning connection. Vapor transport by tropical deep convection dominates upper troposphere humidity all over the globe. This is how lightning activity is related to humidity up there. Global integrated lightning activity is measured by Schumann resonance amplitudes. It is a sensitive device, for there are about fifty lightning events/sec on earth, so excitation of the lowest 8-30 Hz modes is a quasi-continuous process not subject to serious statistical fluctuations. No long term trend in SR, no enhancement of tropical deep convection, no increase in upper troposphere specific humidity, water vapor feedback can't be strong positive. You have a problem which would not go away by hand waving. "As you did on the other thread about tropospheric water vapour" It is not finished there, just discontinued. Specific humidity even at 700 hPa is decreasing slightly as measured by radiosondes. It is not a level where instrumental problems are manifest. http://www.skepticalscience.com/news.php?p=2&t=68&&n=117#7377 -
carrot eater at 10:19 AM on 31 January 2010On the reliability of the U.S. Surface Temperature Record
sbarron2000: Take the max and min data shown, and take the average. That'll pretty much suffice. As for homogenisation: Again, I haven't taken the time to appreciate mechanics of the new pairwise algorithm yet, but as far as I'm concerned, the proof is in the pudding. After homogenisation, the 'poor' stations look just like the 'good', the liquid-in-glass look pretty much like the MMTS, and they all look like the US CRN network (which were purposefully sited ideally some time back). Seems like it's doing OK to me. And again, you'll see the major adjustment to the 'good' stations here was TOB, which is separate from the pairwise homogenisation. -
Tom Dayton at 10:05 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Berenyi Peter, Wikipedia says "A strong link between global lightning and global temperature has not been experimentally confirmed as of 2008." Here are some peer-reviewed articles backing up that summary: Williams (2009, in Atmospheric Research) wrote in section 11, "Global circuit response to climate change," "The global circuit response to temperature change on still longer time scales remains an outstanding question (Williams, 2005, Satori et al., 2008). The best current evidence is that the global circuit is stable on long time scales, but the quantitative record is quite short, about half a century (Markson, 2007).... Lightning detection networks are often varying with time (addition of sensors, improvements in signal processing, etc) and this can complicate assessments of long-term trends." Williams (2005, in Atmospheric Research) wrote in the abstract "lightning is responsive to temperature on many time scales, but the sensitivity to temperature appears to diminish at the longer time scales." In the body of the article, "The evidence that lightning responds positively to temperature on all of the foregoing time scales does not guarantee a pronounced global circuit response to temperature. The key issue here is convective adjustment." -
chris at 09:26 AM on 31 January 2010Lessons from the Monckton/Plimer debate
re #27/36 Berényi Péter "Once again. Forget communication & messages, it is not the scientist's field of expertise. Go for truth instead." Careful with attempts at "truth" Peter. As you did on the other thread about tropospheric water vapour, you're attempting to bypass the essential element of scientific enquiry which is evidence. Attempts at "truth" might be used to bolster weak, non-scientific positions, but it’s usually obvious if these don't accord with the evidence. That's the case with your lightning/upper tropospheric water vapour (UTWV) idea. I think you've misunderstood the papers of the scientists that you cite (O. Pinto Jr. and I.R.C.A. Pinto; and C. Price and M. Asfur). The essential point is not that enhanced lightening is expected in a warming world due to enhanced UTWV; in fact lightning is a means of (temporarily) enhancing UTWV (and aiding equilibration of water vapour in the UT), and the use of lightening as a proxy for UTWV should be seen in that light; it’s a potential means of determining the variability in UTWV. That’s clear from the recent papers of your scientists: e.g.: Pinto O and Pinto IRCA (2008) On the sensitivity of cloud-to-ground lightning activity to surface air temperature changes at different timescales in Sao Paulo, Brazil J. Geophys. Res. 113, D20123 http://www.agu.org/pubs/crossref/2008/2008JD009841.shtml These authors describe the expectation that lightning should increase in a warming world, and show that their own data from Brazil is consistent with models in predicting enhanced lightning above an enhanced surface warmth in the decades from 1950-1990. They point out that there isn’t good evidence for long term global lightning trends, but state that this may be due to limited and localized analyses and the fact that lightning predominates in the tropics whereas warming as dominated in the temperate and polar regions. These authors say nothing about the relationship between lightning and UTWV other than to point out that Price and Asfur have attempted to relate variability in UTWV to lightning (i.e. lightning is the cause of temporarily enhanced UTWV since the associated phenomena aid in transporting water vapour to high altitudes). This is very clearly stated in the recent papers of Price and Asfur. For example: Price C (2009) Will a drier climate result in more lightning? Atmos. Res. 91, 479-484Previous studies have indicated that increased lightning activity will moisten the upper troposphere ([Price, 2000] and [Price and Asfur, 2006a]). Hence, a drier surface resulting in a wetter upper atmosphere also appears to present a contradiction. However, in a warmer climate the enhanced evaporation from the oceans, together with the increased moisture-holding capacity of the atmosphere, leads to higher specific humidities in the atmosphere. When thunderstorms develop in this moister environment, there is more water vapor available for transport aloft into the upper troposphere. Since the upper troposphere is naturally extremely dry, increasing the intensity of thunderstorms in a warmer climate will indeed moisten the upper troposphere, even though the surface layer may be drier due to enhanced evapo-transpiration, and/or decreases in the amount of rainfall.
And Price and Asfur, point out that there is a good match between lightning activity and the subsequent change in UTWV (due to the causality indicated above), and therefore lightning activity could be a potentially useful means of estimating UTWV variability, which they assess by comparing lightning data with independent UTWV measures from NCEP. Price and Asfur are in agreement with the evidence that increased global warming has resulted in enhanced UTWV; their analysis is a potential means of assessing daily variability in UTWV (over continents but not over oceans): Price C, Asfur M (2006) Can lightning observations be used as an indicator of upper-tropospheric water vapor variability? Bull. Amer. Met. Soc. 87, 292-298 http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2FBAMS-87-3-291 So global lightning isn’t a proxy for global UTWV. However since lightning is part of the atmospheric phenomenon that facilitates transport of tropospheric water to the UT, thunderstorm and lighting variability are expected to result in consequent UTWV variability in the short term (Price and Asfur consider it debatable whether the lighting – UTWV response will be manifest on changing the temporal scale from daily to monthly, seasonally or longer term), and that’s the basis for their analysis. Of course if we want to determine UTWV we really have to do the hard work of careful satellite monitoring or get to grips with the (so far imperfect) radiosonde reanalyses…. -
chris at 09:16 AM on 31 January 2010Lessons from the Monckton/Plimer debate
EdB, the ultimate arbiter of scientific analysis is time and the cauldron of subsequent research and critique. If one is interested in the paleoclimate of the last millenium or two, one looks at the scientific evidence (lots of this presented in recent posts on this thread). Mann's original analysis has been hugely stimulating of an entire scientific field, and the subsequent analysis using a range of methods, has come up with broadly similar conclusions about the anomalous nature of late 20th century and contemporary warming. If Mann was so wrong, how come he seems to have been right? That's the beauty of the scientific method Ed. Reality supercedes politics. It would be unfortunate to fixate on a political "enquiry", and ignore the reality of a wealth of scientific data... -
Berényi Péter at 08:41 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Riccardo, Pinto & Pinto have found that a single degree centigrade of local surface temperature change is enough to increase lightning activity by as much as 30-40%, independent of timescale. An effect of this magnitude is also predicted by climate models. The coupling is prominent, one can not possibly miss it, provided warming occurs indeed. On the other hand, via Schumann resonance no increase in global integrated lightning activity is observed on multidecadal scales. It follows, that both temperature trend reconstructions and mainstream climate models are in serious trouble. Indirect measurement is fine as long as the measurement process and device is tightly controlled and the physics is understood. Neither one of these assumptions hold for the kinds of indirect measurements AGW theory is based on. OHC would be a good indicator if it were measured. In fact it is only measured with reasonable resolution since late 2003 and only for the upper 750 m or so of the oceans. Not much increase is observed for this period, all else is the usual mess of ad hoc "adjustments". Measuring the low frequency modes of Schumann resonance is a beautiful hack. It effectively uses the entire Earth as a high precision measurement device. It is not an effect masked by all kinds of biases, spurious noise sources, instrument changes, calibration problems and the like. Also, long term measurement projects are not controlled by the climate crowd, but geophysicists. I wonder what should happen to force you to consider constant UTRH climate models getting falsified. If no conceivable state of affairs is sufficient to do that, the models are so slippery, they have no scientific merit whatsoever. As for being harsh. Please, do that, I am not touchy. In science going for truth is a better predisposition than going for PR exploits, influence, glory, power, money and the like. If it is arrogant, so be it. -
chris at 08:11 AM on 31 January 2010Lessons from the Monckton/Plimer debate
EdB this site is pretty good at focusing on the science, and you’re not going to make much headway with that stuff. I wonder if you’d really be happy with a world in which science was “decided” by political committees! In fact there have been a large number of paleoproxy analyses of past temperatures since Mann's original papers. These pretty uniformly support the essential conclusions of the 1998/9 Mann et al reconstructions, with no evidence (in N Hemisphere reconstructions) of any periods during the past couple of millennia that were warmer than the temperatures around the middle of the 20th century (i.e. the evidence indicates that the contemporary N. hemisphere is already around 0.6-0.9 oC warmer than during the warmest period of the last 2000 years). All of the published paleoreconstructions place the late 20th century and contemporary warming as being anomalous in the context of the last two millennia much as Mann et al proposed in 1998. The paleoproxy data is archived here, and there’s no excuse in not addressing the scientific evidence that supports this conclusion: http://www.ncdc.noaa.gov/paleo/recons.html Otherwise, it’s difficult to understand your posts. I’ve just looked in the database for papers by the McIntyre person that you have mentioned and there simply isn’t anything there that addresses this subject (apart from a few paragraphs of unsubstantiated complaints against Mann et al's 2008 paper in PNAS). Wahl and Ammann published an enormously detailed paper that essentially validated the Mann et al proxy analysis in relation to detailed methodologies, and demonstrated that the McIntyre critique was without merit: Wahl ER, Ammann CM (2007) Robustness of the Mann, Bradley, Hughes reconstruction of Northern Hemisphere surface temperatures: Examination of criticisms based on the nature and processing of proxy climate evidence Climatic Change 85, 33-69 Your McIntyre chap hasn’t responded in the scientific literature, so clearly there’s nothing substantively wrong with the Mann et al or Wahl and Ammann’s analyses that warrents a critical analysis in the scientific literature. In any case this is very, very old news and we don’t have to keep on pretending that all of our understanding of paleoclimate rests on a paper from 12 years ago! If we're interested in the science we really should be addressing the evidence. -
SNRatio at 07:31 AM on 31 January 2010The IPCC's 2035 prediction about Himalayan glaciers
@39 Berényi Péter Peer review only implies that _some_ kind of quality control has been applied. Lots of crap pass through all the time, the basic premise is not that it is correct, but that it could be, and that the bad parts will be contradicted by new work and left behind. This is certainly not good enough, as we have a number of recent examples to demonstrate. In this situation, using results just because they have passed peer review is certainly not very skeptical. -
sbarron2000 at 07:07 AM on 31 January 2010On the reliability of the U.S. Surface Temperature Record
Carrot eater: yes, the means. -
Riccardo at 06:51 AM on 31 January 2010Lessons from the Monckton/Plimer debate
EdB, exactly what I said, you were looking for it, not at the broad picture of the science of temperature reconstruction. -
EdB at 06:40 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Riccardo The Wegman report was easy to find. It pops up in Wikipedia. -
jmath at 06:38 AM on 31 January 2010Tree-rings diverge from temperature after 1960
I am confused. THere seems to be a logic problem here. If the proxies are incorrect post 1960 or there is a divergence at one time and you don't really KNOW the cause for that divergence then how can anybody conclude that there weren't other divergences you didn't understand in the past? Just because we don't see divergence between north and south there could be something which affected tree ring data over any period of time in the past either depressing or increasing temperatures that actually ocurred. You really can't have any confidence in this proxy until you understand the cause. What if the cause is caused by droughts? What if there was a large drought over the areas north and south covered by these trees? What if there was a huge flood or volcanoes or some other co-incidence like a increase in acidification due to some bacterial or animal or plant extinction or proliferation? The point is not the specifc thing but the logic being used here which is flawed by you guys. The fact is that the "science" is still very nascent and major things like what is affecting tree ring densities and widths is not really understoof even TODAY let alone 1,000 years ago. It is hard to have confidence in you "scientist" proclamations when a simple computer scientist from MIT can see the logical flaws in your arguments. Maybe because I was trained in math and physics my expectations as to logic and proof are much more stringent. For instance, the idea you can use these proxies and eliminate trees so easily, use so few and not have a well understood rigorous process for these things leaves me totally skeptical. This doesn't seem to qualift as science but more like "social science" which is based on surveys and self-reported data. A lot of the climate science stuff strikes me as having these logical errors. For instance, the models are built and calibrated, initialized to match historical data, then "scientists" say they match history good and predict the future. That's just falacious reasoning. I can construct many milllions of models which match history but which fail immediately to predict the future. In fact that looks to be exactly the case. Modelers admit (from what I've read) that they cannot explain current 10 year trends, whether down or flat or even up a little they don't correspond to any models output. WHereas these models are more accurate in past temperature predictions. Of course they are, they are not used UNLESS they fit past temperature records. But that does not give them ANY credibility in saying they "predict" the future. That would have to wait for confirmation that they actually DO predict temperatures and so far they aren't. Doesn't that pretty much say the models are flawed? Even if you say the models represent almost all relevant factors the errors introduced by their mathematical nature means that the ability to say with any assurance the predictions have a numerical preciseness is almost impossible. The temperatures could be -10 or +30 and still be in the models error bars. So there is no predictive power possible even if the models were correct. We would all be better reverting to a simplification and look at the earth as one giant thermodynamic entity than trying to break it into pieces and understand interelationships in the pieces at a micro level. THis just seems numerically implausible to return any level of accuracy useful over even a few iterations. -
Riccardo at 06:35 AM on 31 January 2010Lessons from the Monckton/Plimer debate
EdB, it's really enlghtning that you quote a politically recruted team that published a non-peer revewd report and not, for example, the National Research Council Report or the tons of other published papers. Is it a bias in the google search engine or somewhere else? Assuming you asked google the same thing you asked here, i tryed both "hockey stick controversy" and "hockey stick broken" but the Wegman Report didn't show up in the first 10 results ... -
EdB at 06:35 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Doug.. I don't think realclimate is telling the story correctly as Wegman deals with this:(surely after such expert testimony you must concede that the hockey stick is well and truly broken? Q. Do you agree or disagree with Wahl and Ammann’s finding that the time period used to center the data does not significantly affect the results reported in the MBH98 paper? If you disagree, please state the basis for your disagreement. Were you aware of their reanalysis of MBH99 prior to the time you finalized your report? Do you agree or disagree with their reanalysis of MBH99? If you disagree, please state the basis for your disagreement. Ans: We do disagree. The fundamental issue focuses on the North American Tree Ring proxy series, which Wahl and Ammann admit are problematic in carrying temperature data. In the original MBH decentered series, the hockey-stick shape emerged in the PC1 series because of reasons we have articulated in both our report and our testimony. In the original MBH papers, it was argued that this PC1 proxy was sufficient. We note the following from Wahl and Ammann. “Thus, the number of PCs required to summarize the underlying proxy data changes depending on the approach chosen. Here we verify the impact of the choice of different numbers of PCs that are included in the climate reconstruction procedure. Systematic examination of the Gaspé-restricted reconstructions using 2-5 proxy PCs derived from MM-centered, but unstandardized data demonstrates changes in reconstruction as more PCs are added, indicating a significant change in information provided by the PC series. When two or three PCs are used, the resulting reconstructions are functionally equivalent to reconstructions in which the bristlecone/foxtail pine records are directly excluded When four or five PCs are used, the resulting reconstructions are virtually indistinguishableand are very similar to scenario 5b.” Wahl and Ammann. Without attempting to describe the technical detail, the bottom line is that, in the MBH original, the hockey stick emerged in PC1 from the bristlecone/foxtail pines. If one centers the data properly the hockey stick does not emerge until PC4. Thus, a substantial change in strategy is required in the MBH reconstruction in order to achieve the hockey stick, a strategy which was specifically eschewed in MBH. In Wahl and Ammann’s own words, the centering does significantly affect the results. Yes, we were aware of the Wahl and Ammann simulation. We continue to disagree with the reanalysis for several reasons. Even granting the unbiasedness of the Wahl and Ammann study in favor of his advisor’s methodology and the fact that it is not a published refereed paper, the reconstructions mentioned by Dr. Gulledge, and illustrated in his testimony, fail to account for the effects of the bristlecone/foxtail pines. Wahl and Ammann reject this criticism of MM based on the fact that if one adds enough principal components back into the proxy, one obtains the hockey stick shape again. This is precisely the point of contention. It is a point we made in our testimony and that Wahl and Ammann make as well. A cardinal rule of statistical inference is that the method of analysis must be decided before looking at the data. The rules and strategy of analysis cannot be changed in order to obtain the desired result. Such a strategy carries no statistical integrity and cannot be used as a basis for drawing sound inferential conclusions.' -
Doug Bostrom at 06:09 AM on 31 January 2010Lessons from the Monckton/Plimer debate
EdB at 05:55 AM on 31 January, 2010 Useful to read this: "Wegman had been tasked solely to evaluate whether the McIntyre and McKitrick (2005) (MM05) criticism of Mann, Bradley and Hughes (1998) (MBH) had statistical merit. That is, was their narrow point on the impacts of centering on the first principal component (PC) correct? He was pointedly not asked whether it made any difference to the final MBH reconstruction and so he did not attempt to evaluate that. Since no one has ever disputed MM05’s arithmetic (only their inferences), he along with the everyone else found that, yes, centering conventions make a difference to the first PC. This was acknowledged way back when and so should not come as a surprise. From this, Wegman concluded that more statisticians should be consulted in paleo-climate work. Actually, on this point most people would agree – both fields benefit from examining the different kinds of problems that arise in climate data than in standard statistical problems and coming up with novel solutions, and like most good ideas it has already been thought of. For instance, NCAR has run a program on statistical climatology for years and the head of that program (Doug Nychka) was directly consulted for the Wahl and Ammann (2006) paper for instance. But, and this is where the missing piece comes in, no-one (with sole and impressive exception of Hans von Storch during the Q&A) went on to mention what the effect of the PC centering changes would have had on the final reconstruction – that is, after all the N. American PCs had been put in with the other data and used to make the hemispheric mean temperature estimate. Beacuse, let’s face it, it was the final reconstruction that got everyone’s attention.Von Storch got it absolutely right – it would make no practical difference at all. " Illustrations here: http://www.realclimate.org/index.php/archives/2006/07/the-missing-piece-at-the-wegman-hearing/ -
EdB at 05:55 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Riccardo: your response to my question about the hockey stick. I am puzzled by your references as the records I Googled shows that the hockey stick is broken: The Wegman report to the US Senate says this: Mann's decentred methodology is simply incorrect mathematics …. I am baffled by the claim that the incorrect method doesn’t matter because the answer is correct anyway. Method Wrong + Answer Correct = Bad Science. And in Wegmans reply to Senator Stupak he says the following about Wahl and Ammann (2006): It is our understanding that when using the same proxies as and the same methodology as MM, Wahl and Ammann essentially reproduce the MM curves. Thus, far from disproving the MM work, they reinforce the MM work. The debate then is over the proxies and the exact algorithms as it always has been. The fact that Wahl and Ammann (2006) admit that the results of the MBH methodology does not coincide with the results of other methods such as borehole methods and atmospheric-ocean general circulation models and that Wahl and Ammann adjust the MBH methodology to include the PC4 bristlecone/foxtail pine effects are significant reasons we believe that the Wahl and Amman paper does not convincingly demonstrate the validity of the MBH methodology. -
carrot eater at 05:53 AM on 31 January 2010On the reliability of the U.S. Surface Temperature Record
sbarron: do you want to see the means, instead of just max and min? I don't quite follow. -
J Bowers at 05:52 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Berényi Péter at 21:45 PM on 30 January, 2010 "Once again. Forget communication & messages, it is not the scientist's field of expertise. Go for truth instead. " Read up on Hugh Hammond Bennett, scientist and 'political player', and how both his scientific endeavour plus ability to play the political game led to solving the Dust Bowl problem of the Great Depression. http://www.soil.ncsu.edu/about/century/hugh.html Pay close attention to the trick he used during a crucial Senate committee in March 1935; something many scientists would be pilloried for today, but then most in the US would also be eating sand today ;) -
carrot eater at 05:42 AM on 31 January 2010On the reliability of the U.S. Surface Temperature Record
Philip64: The SPPI report is just a grab-bag of old nonsense. Most of it is based on simple understandings of how anomalies are used, as well as weird conspiracy theories about stations. The conspiracy theory about station-dropoff is easily dismissed by looking an openly published papers from long ago about the sources of the GHCN, and is further discussed here. http://www.yaleclimatemediaforum.org/2010/01/kusi-noaa-nasa/ -
Riccardo at 04:52 AM on 31 January 2010On the reliability of the U.S. Surface Temperature Record
Philip64, not sure i'll waste my time going through it because, looking at just the table of content, they do not address the only relevant point, the impact on the temperature records. All the rest (111 pages!) is propaganda. -
Doug Bostrom at 04:49 AM on 31 January 2010Peer reviewed impacts of global warming
Berényi Péter at 22:18 PM on 30 January, 2010 "What is more, they would not even promote economic, intellectual & spiritual development in those regions. Glass beads for the natives. " Avast there, you have to spend more time looking, less time thinking! That whole sentence was conjecture, and wrong. You can do better. In point of fact, one of the remarkable benefits of these tiny private solar installations I've described is the gift of reading. In the kind of subsistence economy I'm speaking of, these devices mean the difference between being able to read versus sitting in the dark. They have been a boon to education. And it's a global phenomenon, most visible in Africa but true also for instance in Mongolia or wherever a grid is not present. No, 15W panels are not going to supplant Western style grids. I guess my original point was, the first 15W bring a huge benefit; a little electricity brings a significant fraction of the benefits of electrification and this is particularly visible where a grid has not inculcated huge expectations and waste. Perhaps also as with the example of cellular phones leapfrogging copper telecommunications systems in developing nations, assuming that a Western style grid is a mandatory prerequisite for social progress is something to consider carefully. -
Riccardo at 04:47 AM on 31 January 2010On the reliability of the U.S. Surface Temperature Record
sbarron2000, "Fortunately, the sites with good exposure, though small in number, are reasonably well distributed across the country and, as shown by Vose and Menne [2004], are of sufficient density to obtain a robust estimate of the CONUS average (see their Fig. 7)" They have 71 good stations. In Vose and Menne 2004 they found that the coefficient of determination for both maximum and minimum temperature reaches 95% already with 25 stations. There's no reason for concern. -
Doug Bostrom at 04:33 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Berényi Péter at 21:45 PM on 30 January, 2010 "Once again. Forget communication & messages, it is not the scientist's field of expertise. Go for truth instead. " Many scientists have made human communications their primary field of inquiry. Humans of course must be treated as something akin to molecules of gas when it comes to making predictions of aggregate populations, but it is possible to make predictions about human integration of new ideas into existing mental models with a fair degree of confidence Unfortunately, scientific research on communications indicates that conveying truth is not always a simple or easy task, even when the truth being conveyed is not accompanied by controversy and competing attempts to distort understanding. Even when a third party is not waving a brightly colored, distracting blanket and yelling "Hey, look over here!", effectively conveying such things as the difference between weather and climate is fairly challenging. Selecting a means of conveying a concept that is robust against such challenges improves the probability that any given recipient's understanding will be improved. As to ocean heat content, the measurement issues you mention can be resolved easily enough for relatively microscopic amounts of money, sufficient to yield numbers with reasonable confidence. The very little that has been spent on that effort is entirely encouraging. -
sbarron2000 at 04:11 AM on 31 January 2010On the reliability of the U.S. Surface Temperature Record
Also, why does Menne 2010 not provide an average temperature in C anomaly chart that compares adjusted and unadjusted good sites and bad sites? Wouldn't that be the easiest way to show whether there is a difference between the two types of sites? Right now it only provides maximum and minimum anomaly comparisons. Which while interesting, and I'm sure you can learn a lot from them, isn't really the standard way which we compare temp anomaly, is it? -
sbarron2000 at 04:03 AM on 31 January 2010On the reliability of the U.S. Surface Temperature Record
Riccardo, I agree with you that there is plenty of room for good readings. But are the stations in question in such locations? Because if they're not, then the difference of means adjustment appears to attempt to correct tainted measurements using other tainted measurements. That can't be a good thing, can it? Carrot eater, I'll be the first to admit that I don't fully understand what the difference in means test is doing. I have only glanced at Menne 2009, and would probably need to see the actual calcs to figure out how the test is conducted anyway. My comment is only intended as a way to consider the adjustments that Menne 2010 makes, and its possible effects on its findings. Like, what is the effect of running the difference of means test on data that you know is considered poor, because of the site rating? Like must be done when Menne 2010 seperates the good sites from the bad. Does correcting badly sited temp stations using other badly sited temp stations have some unforseen effects? The same is done to the good sites, and there are way fewer of them. So any influence might have a larger impact with the smaller sample. Just thinking out loud again. -
Albatross at 04:01 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Someone has been talking about global thunderstorm activity and global warming. First, it is important to remember that we do not have a long record of reliable global lightning flash data (accuracy ~500 m, detection rate >80%). In N. America there are only about 10 yrs worth of spatially and temporally continuous lightning data (and coverage over the Tundra and Arctic is not great). This is not really long enough to draw any conclusions regarding trends. There are some global lightning networks which use a variety of technologies, but they miss a large portion of the strikes/flashes. There are also remotely sensed lightning data from space, but these can only detect nocturnal lightning. Anyhow, so we still do not have a monitoring system that adequately captures and quantifies global lightning activity. For a thunderstorm to form one requires: 1) Instability; 2) Low-level moisture and 3) A trigger mechanism to lift a "parcel" to its level of free convection (LFC). Note that temperature does not appear explicitly(it is included implicitly in all three though, e.g., increase in instability through differential heating in the vertical, air can hold more WV as temp. goes up, surface heating may be enough alone to lift parcels to their LFC), and that each one of these requirements is alone not a necessary and sufficient condition for a thunderstorm. All three need to be satisfied simultaneously. So, as someone who has some expertise int his area, would argue that lightning is not necessarily the best metric for tracking global warming, and also, that we are really not in a position yet to adequately monitor global lightning activity. There are suggestions that lightning actvity may be increasing over high latitudes of continents in the N. Hemisphere in response ot the warming there, although we do not really have sufficient data yet to speak to trends. Anyhow, my point is that is there is a strong lightning signal to GW, then it will likely be evident in lightning activity over high-latitude continental areas in the N. Hemisphere during the warm season. PS: One must also remember that GW may also result in more lightning activity in some areas, but less activity in others b/c of desertification, for example. -
Philippe Chantreau at 03:33 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Keep your hasty judgments to yourself RSVP, my computer is powered by hydro. -
Philip64 at 02:41 AM on 31 January 2010On the reliability of the U.S. Surface Temperature Record
Watts and d'Aleo have just published this paper at Robert Ferguson's 'Science and Public Policy Institute'. It's claims are pretty wild. Apparently we can throw all temperature records out the window, because ALL of them are effectively faked. It might be worth addressing these claims in detail, if time can be found. http://scienceandpublicpolicy.org/images/stories/papers/originals/surface_temp.pdf -
Riccardo at 02:27 AM on 31 January 2010Lessons from the Monckton/Plimer debate
EdB, unfortunately the hockey stick is stil there, up and running. More on the divergence problem here -
EdB at 01:55 AM on 31 January 2010Lessons from the Monckton/Plimer debate
I'm new here. Can someone explain how the proxy records validate that the Medieval warm period was cooler? I thought McIntyre demolished the Hockey stick(Mann), and the Yamal tree(Briffa)? What other reconstructions are out there that prove it?Response: EdB, welcome to Skeptical Science. Just one reminder - please post comments on the relevant page. A search for hockey stick (note the search form in the left margin) would point you towards the hockey stick is broken page. Here, you will learn that since Mann's hockey stick paper in 1999, there have been a number of temperature reconstructions made using a variety of techniques (not just the PCA analysis employed by Mann) from a number of different proxies (eg - stalagmites, ice cores, boreholes, tree rings, etc).
Then if you have any further questions, you can continue the discussion there which is the best place for such a topic. -
Marcel Bökstedt at 01:43 AM on 31 January 2010Lessons from the Monckton/Plimer debate
> Berényi Péter I agree with you that monitoring the global average of the surface temperature is not the best way to measure climate change, and that OHC sounds like a more interesting number. As you say, it might not be so easy to measure this. You might be able to estimate how much heat going in or out at the surface of the ocean, but there might also be unknown heat exchange between the ocean and the underlying rocks - or maybe you can ignore this? Anyhow, you claim that OHC is decreasing. This does not seem to agree with the source cited at http://www.skepticalscience.com/Does-ocean-cooling-disprove-global-warming.html. Do you have some reference to back up your claim? I do not understand the relevance of lightening activity - why is there a strong relation between this and global temperature? Even granted this and granted your claim that global lightening activity is constant, why does this measure anything more relevant than surface temperature which we measure directly anyhow, and which we seem to agree is not necessarily the best parameter to monitor. -
Riccardo at 01:27 AM on 31 January 2010Lessons from the Monckton/Plimer debate
RSVP, not sure to represent the thinking of our guest, but it looks like this site is devoted to science more than technology. Although very interesting and important, it's outside the scope of this blog. IMHO.Response: My original plan was to begin with a focus on science and as the public debate moved on from the scientific question of what's causing global warming into the question of what to do about it, Skeptical Science would move into that area too. I must confess we're not as far along as I expected to be at this point. -
Riccardo at 01:20 AM on 31 January 2010Lessons from the Monckton/Plimer debate
Berényi Péter, you put a lot of different pieces together trying to disprove all of them. Let me pick them one by one and let me not quoting the relevant scientific articles to save time; they can easily be found if you're interested. it looks like you are not much confident with indirect measurement. Although the problem of AGW si definitely a problem of energy imbalance, temperature is one of its manifestation. It is (good old) standard practice in science to use indirect measurements to guess what is not accessible directly. OCH is a good indicator and it has been increasing for decades. Do you want to bet using just a few recent years? Is this a "standad statistical practice"? And why limit to a depth of 750 m? In the end, OCH in not so well characterized as anyone may wish and surface temperature do a good enough job. On this last point, you are missing that most part of the temperature record does not come from land. Indeed throughout the oceans the surface temperature is assumed to be the sea surface temperature and, surprise!, there's no controversy between the various data sets, at least if the "standard statistical practice" applies. Sea level measurements do NOT depend on any particular tide gauge and crustal upward/downward motion is quite well known and often measured. The relation between SLR and temperature is uncertain to the extent the other contribution (other than temperature) can be evaluated. It can be done and, allowing for the uncertainties, the are not contradictory. Please excuse me if i'll be i little harsh in what follow, but too often you sceptics claim to have found the smoking gun, the nail in the coffins, the final word. It just makes apparent your desire to put the discussion to an end. The last "infatuation" for the lightnings is silly. It's not a well characterized technique and, above all, it does not represent the whole water vapour content, even of just the upper troposphere/lower stratosphere. True that water vapour is carried there by strong upward transport in thunderstorms but it's not the whole story, not even the largest part but what is measured is the frequency of the events, not the amount of water vapour carried up in the atmopshere. There are no nails in the coffin here, just one more little piece of information; claiming that it "falsify the models" is absurd and inviting us to "go for truth" is arrogant. -
SNRatio at 00:28 AM on 31 January 2010The IPCC's 2035 prediction about Himalayan glaciers
@39 Berényi Péter Peer review only implies that _some_ kind of quality control has been applied. Lots of crap pass through all the time, the basic premise is not that it is correct, but that it could be, and that the bad parts will be contradicted by new work and left behind. This is certainly not good enough, as we have a number of recent examples to demonstrate. In this situation, using results just because they have passed peer review is certainly not very skeptical. -
SNRatio at 00:01 AM on 31 January 2010The IPCC's 2035 prediction about Himalayan glaciers
32, @koyaanisqatsi The standard value for the dry adiabatic lapse rate is 9.8 deg C/km. Just compare observed mean surface temperatures vs height in the same regions, and compare to the lapse rate. In warming, the height/melting temperature point would follow approximately that curve, not the lapse rate. Which is why glaciers are very sensitive to temperature, not insensitive as the lapse rate relation would imply. Freezing level is not the only determinant either, for temperature, precipitation and their relationship is not constant, and sublimation may also be important. -
Lessons from the Monckton/Plimer debate
Yet another article that fails to stimulate a more informed debate between the main protagonists of the pro and anti AGW camps. Why was Ian Plimer not invited to respond directly to the contents of this article and the subsequent postings? Who knows, we all may learn something from such an exchange of views which could help us to inch forward in creating a broader consensus of the issue of climate change and the most appropriate mitigating measures that should be implemented. -
RSVP at 22:26 PM on 30 January 2010Lessons from the Monckton/Plimer debate
Berényi Péter You are definitely speaking in the right direction. I would add that temperature matters as far as total ocean temperature averages. The issue as you say is all about energy, not weather. Weather is but a symptom. The other side of the coin are sustainable energy alternatives, which are played way down at this site. Everybody is waving the flag for change, quantifying the problems, but zero quanitifying when it comes to alternatives. -
Berényi Péter at 22:18 PM on 30 January 2010Peer reviewed impacts of global warming
OK, I see your point. However, small but still expensive solar panels, not produced locally and with no grid or battery backup whatsoever would not change global energy usage patterns. What is more, they would not even promote economic, intellectual & spiritual development in those regions. Glass beads for the natives. -
Miriam O'Brien (Sou) at 21:47 PM on 30 January 2010Lessons from the Monckton/Plimer debate
The article and the comments are interesting and have opened my eyes a bit more about why such discussions are so difficult. In an internet forum discussion when people do not know each other, we naturally tend to relate most to those with whom we agree. Therefore when an 'alarmist' responds impatiently to a 'skeptic' who is simply trolling or flaming or continually interrupting a discussion with silly throw-away lines, other skeptics react as if the impatient response is directed at all skeptics and 'group offense' is taken. Re scientists and the public, I'm betting that many scientists rarely mix with people of normal intelligence let alone people of low intelligence. When they socialise outside their field it is generally with people of equal or nearly equal intellect, so they aren't that practiced at communicating with the person in the street. Nor should they have to. That's the job of science communicators. Actors like Monckton appeal to emotion not intellect. For many people, emotion is a much more powerful force than reason. I bet most people who attend Monckton's performances don't even remember what his 'arguments' are, but they do remember the force with which he put them and that they agree with him, whatever he said. -
Berényi Péter at 21:45 PM on 30 January 2010Lessons from the Monckton/Plimer debate
doug_bostrom at 12:13 PM on 30 January, 2010 "I wonder if making surface temperature the main communications message regarding climate change is not a fairly big mistake. Surface temperature is a crummy proxy for measuring actual climate change, especially when oceans dominate the scene. We don't live in the ocean, after all, yet oceans are where most of the current energy perturbation is going" It IS a mistake. As you say, average surface temperature is a "crummy proxy". It's NOT just a matter of communication skills, it really is one. There is simply no physical law about "conservation of temperature", temperature budget can neither be measured nor calculated. The very concept does not make sense. Also, surface temperature records suffer from all kinds of biases, trends in global averages ARE controversial. Automatic pattern recognition based data homogenization as it is practiced by climate experts is not a standard statistical procedure. It is NOT used in any other branch of science, and for a reason. OHC (Ocean Heat Contents) is much better. Atmospheric & soil heat content is negligible compared to oceans, most of the stored energy in climate system is heat, because below 30 miles elevation LTH (Local Thermodynamic Equilibrium) holds, and even better, we do have an energy conservation law, so in theory energy budget can be both measured and calculated at TOA (Top of Atmosphere) as the difference between ASR (Absorbed Shortwave Radiation) and OLR (Outgoing Longwave Radiation) fluxes. OHC should follow rather closely the temporal integral of this quantity. Unfortunately measurement is not up to the task yet. The low temporal frequency part of ASR-TOA (which is amplified by integration) is far too noisy to draw any conclusion. On the other hand OHC, at least in the upper 750 m of oceans, if anything, is slightly decreasing right now. There is no known mechanism to transfer and sequester so much extra heat into the abyss (which is not measured) as projected by climate models. Sea level as a proxy to OHC is also problematic. The low temporal frequency part, which determines long term trends, is NOT measured by satellites. It should be calibrated by tide gauges. But they only measure relative elevation changes between sea level and adjacent seashore. As crustal blocks are in continuous vertical motion either up or down comeasurable to sea level changes, the calibration depends on choice of the gauge set to be calibrated against. However, all is not lost. At any one place there is a strong correlation between lightning activity and surface temperatures. You don't even have to be a climate scientist to verify this connection. Global lightning activity can be assessed by measuring Schumann resonance amplitudes at any one spot on the face of earth. And it is measured indeed, since mid 1960s (the effect itself was discovered in 1952). There is NO long term trend detected in Schumann resonance activity. It plainly contradicts current "mainstream" global warming theory. If theory is falsified by measurement, it should be abandoned. It is not a communication issue, just this is how science works. There is NO contradiction between low vs. high climate sensitivity according to Monckton & Plimer as you claim. The very concept of climate "forcing" is flawed. Global climate may be sensitive to some changes (like ice sheet cover, orbital variation or solar UV) while insensitive to others (like CO2). It is not correct to readily covert each forcing to W/m2. They act on different parts of the climate system, can and do have different structural effects. It is certainly not the case that rising carbon dioxide levels have no climatic consequences. The atmosphere should reconfigure itself to accommodate to the changing composition. Even if global integrated heat contents of the system is not going to any definite direction, just fluctuates around an equilibrium level, there still may be transients and regional effects. However, sticking to already falsified models based on the "constant upper troposphere relative humidity principle" (of course there is no law for conservation of RH) is definitely not the way to proceed. This way you don't even have a chance to guess what atmospheric reconfiguration processes might in fact be going on. Once again. Forget communication & messages, it is not the scientist's field of expertise. Go for truth instead. -
HumanityRules at 21:41 PM on 30 January 2010Lessons from the Monckton/Plimer debate
#5 ScaredAmoeba I had a look at http://volcanoes.usgs.gov/hazards/gas/index.php but they reference Gerlach 1991. It seems a well referenced estimate. Anybody read Gerlach 1991? It's an EOS paper so only AGU members get access. Is EOS all opinion, news, reviews, no original data? If that's the case does anybody know the reference for Gerlach estimates? -
RSVP at 21:34 PM on 30 January 2010Lessons from the Monckton/Plimer debate
doug_bostrom A better comparison is one who would like to have a coke with ice in the middle of the desert, and the closest thing to water is a mirage at a 100 yards.
Prev 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 Next
