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Rob Honeycutt at 09:06 AM on 8 May 2010Climate Change and the Integrity of Science: a letter to Science
@skepticstudent... I think you need to step back for just a moment and challenge yourself and your own grasp of the subject matter. We are talking about 255 members of the NAS. These are not your run-of-the-mill PhD's. These are some of the finest minds in the world, and these are also the members of the NAS who are most familiar with climate science. They know of what they speak. One needs to ponder the significance of the statements these people are making. These are NOT willy-nilly assertions. They are making very definitive statements about the state of climate science and the predicament humanity faces. Stop and listen. -
notcynical at 09:03 AM on 8 May 2010Climate Change and the Integrity of Science: a letter to Science
It would be interesting to know how many, if any, members of the Academy were asked to sign and declined to do so. -
skepticstudent at 08:58 AM on 8 May 2010Climate Change and the Integrity of Science: a letter to Science
5.5.The combination of these complex climate changes threatens coastal communities and cities, our food and water supplies, marine and freshwater ecosystems, forests, high mountain environments, and far more. Again, there is no scientific evidence to date that shows any horrendous raising of coastal water. I believe the IPCC worst estimate brought forth in any of the 1-4 assessments was a raising of about 1 foot globally. Where is the catastrophe in a one foot rise in oceanic levels. The seas have risen and lowered far more drastically than that through the ages. If there is any question, I can take you to places in Alaska where ancient natives wrote in rock that is now under water and then other ancients that wrote on rocks which is now dozens of feet from shoreline even at highest of tides. The importance to note is this is at a known native Alaskan fishing village which is over 2000 years old or older. Another good example is Lake Shasta, California. My grandfather grew up there in the latter half of the 19th century. The town he grew up in was flooded and covered by water for 45 years because of heavy rainfall for several decades. It is now uncovered again.Response: Sea level rise is observed by tidal gauges all over the world - you can't judge a global trend by a few anecdotal examples. This trend is confirmed by satellite measurements.
Observations of sea level rise since the IPCC predictions show they have underestimated future sea level rise by not taking into account the accelerating ice loss from Greenland and Antarctica. When this is taken into account, various studies using independent methods have found sea level rise by 2100 in the range of 75cm to 2 metres. -
angliss at 08:55 AM on 8 May 2010Climate Change and the Integrity of Science: a letter to Science
skepticstudent - if you want to be taken seriously here, please supply references and refrain from logical fallacies. Would you care to provide a reference for your claim that winters in Alaska, Washington, Russia, and western Europe have been snowier, as well as evidence that snowier = colder? Also, just because CO2 has followed initial temperature rise over the ice core record, that doesn't mean it's doing so now. This is referred to as a "predictive appeal to history" fallacy, and it's something I addressed here. In fact, given that deglaciations take thousands of years, scientists currently hypothesize that a CO2 feedback in response to a small initial change in insolation is what drives the ultimate transition from a glacial period to an interglacial (Source). -
skepticstudent at 08:53 AM on 8 May 2010Climate Change and the Integrity of Science: a letter to Science
4. Where are the studies that say the oceans are becoming more acidic in nature? I have not seen one. Throw into this again the fact that combined NASA and Remote Sensing Systems study showing oceanic temperatures are showing global oceanic cooling over the last 10-20 years. Are we absolutely positively sure beyond a 100% shadow of a doubt that any possible acidity levels have not been caused by volcanic effluence beneath the oceans surface? I have not seen any exhaustive studies on either side of this comment.Response: I have links to studies on ocean acidification here (note - it is by no means a comprehensive list - I very much welcome anyone willing to submit more peer-reviewed papers to our database). There's also more exposition on ocean acidification here.
The oceans are not cooling. The upper waters show some short-term variability due to exchange of heat with deeper waters. But measurements of ocean heat down to 2000 metres show a steadily warming trend. -
skepticstudent at 08:50 AM on 8 May 2010Climate Change and the Integrity of Science: a letter to Science
3. Again at numerous times in earth history the co2 ppm levels have been 18 to 36 x's higher than they are now so, which natural forces are being overpowered by human interevention. At times when the equator was a sludge pot so hot you'd boil just getting into the water the co2 levels were lower than they are today, there have been an ice age or two where the co2 levels are higher than they are today and there have been times with similar temperatures where the co2 levels were 18x's higher than they are now. Once again there is a statement of previous times natural forces being affected by man's activities but no scientific evidence to back this up. -
Rob Honeycutt at 08:46 AM on 8 May 2010Kung-fu Climate
@poptech...I would also point out, as John just has on his latest post, that the 255 NAS members who signed this letter were the list of members who are MOST familiar with climate science. -
skepticstudent at 08:45 AM on 8 May 2010Climate Change and the Integrity of Science: a letter to Science
2. ***( deforestation surely plays a role, however since many of the farms which stole trees from the South American Rain forests are now growing back in exponential numbers we should see some leveling in that region. Also again CO2 is known to be the 5th least effective of the greenhouse gases and there have been points where it was 7000 to 14000ppm compared to the paultry 385ppm today. Where is the emergency? The earth is still here and has levelled out numerous times. It has been proven numerous times that when you look at things over a million to 10 million year period, it is very obvious that carbon levels follow temperature levels so again what is the emergency? -
skepticstudent at 08:44 AM on 8 May 2010Climate Change and the Integrity of Science: a letter to Science
Let me be the first to respond to this august panel (my compliments to anyone who sits through 4-12 years of science to earn a degree of any kind) 1. **** NO, but a decade of snowy winters in Alaska, Washington, Russia and most of western Europe make a statement towards declining temperatures. -
Rob Honeycutt at 08:34 AM on 8 May 2010Kung-fu Climate
@poptech... The individual degrees these people hold is irrelevant. This is THE top scientific organization in our fine nation. This is a rather large group of HIGHLY accomplished scientists, arguably many of the finest living scientists humanity has to offer. Their issue is not about climate science per se. It is about the outside political and special interest forces being exerted on their colleagues. They are also making a clears statement that the climate science is sound, to the point of declaring it a "theory" same as evolution and the big bang, and stating that it can be viewed as fact. These are extremely definitive terms they are choosing to lay out. And they are also stating that climate science is, at the same time, a process of discovery that involves, as I have pointed out, disagreements. But you can't take the disagreements and hold them up to suggest that AGW is not real, anymore than you can hold up a disagreement in evolution and hold that up to suggest that evolution is not real. -
MarkR at 07:40 AM on 8 May 2010University of Queensland talk wrap-up
cdion: the argument seems quite complex in the papers I've read (Hansen did one in '95 iirc), involving interactions with clouds too... But one simple explanation might be that days are cooler than nights. Heat flow is related to temperature by something like Planck's Law (accounting for emissivity), dQ/dt = A ε σ T4 (that's heat flow proportional to temperature to the power 4, the other symbols are constants). If you change heat flow by a given amount, a hotter thing will warm up less than a cooler thing will. To increase from a T of '1' to a T of '2' requires an increase in heat flow of 15/(Aσε) (from '1' to '16'). To increase from a temp of '5' to a temp of '6' requires an increase in heat flow of 671/(Aσε) units. So if you add a heat flow of 15/(Aσε) from, say, greenhouse gases, you could warm something from 1K to 2K, or from 5K to something like 5.02K. i.e. nights should warm faster than days. Once again though, the real argument seems pretty complex; with the full observations requiring greenhouse gases and cloud changes and scientists seem to take a full paper to explain it! Maybe a quick look at Hansen's '95 paper is worth a go, you've reminded me to check it again when I next have time! -
Tom Dayton at 07:36 AM on 8 May 2010Kung-fu Climate
Poptech, instead of pasting large blocks of content from other sites (your comment with that was deleted), you should link to the original site. In response to your request, no I will not do that research for you. The signers of the letter are listed at the bottom of the letter, and their affiliations are listed in the supporting material. But if you want to argue about how many scientists take which position, the appropriate thread is not this one. Instead, post on There is no consensus or on the threads listed in the "Related Arguments" green box at the bottom of that one. -
carrot eater at 07:30 AM on 8 May 2010Kung-fu Climate
This is turning into a mere exercise of digging up things other people have said somewhere. Which is useful inasmuch as they're relevant, but simply linking something is not the same as reading it, understanding it, critically assessing it, and then discussing it. Simply showing that something exists does not demonstrate that it is valid. Granted, for somebody who isn't a specialist in paleoclimate (and I surely am not; I'm not even that interested in it), there's only so much time you might want to devote to getting into it. No one person can be an expert in all things. I applaud robhon for being upfront, that he isn't a specialist, but that he appreciates that the process works out - science proceeds over time. -
Riccardo at 07:20 AM on 8 May 2010Kung-fu Climate
Again, as in the main post, this is just a useless fight. This kind of argiung is not in the interest of adding something to the science. There's something really a-scientific behind it. Sentences like "Defending Mann's work is the equivalent of defending the Titanic as unsinkable" means absolutely nothing but make clear the intention. Which is unacceptable. -
Tom Dayton at 06:57 AM on 8 May 2010Kung-fu Climate
Poptech, the letter from a great many members of the National Academy of Sciences was published in the May 7 issue of the journal Science. -
Rob Honeycutt at 06:47 AM on 8 May 2010Kung-fu Climate
The NAS letter is about YOU. -
Rob Honeycutt at 06:39 AM on 8 May 2010Kung-fu Climate
@poptech... It takes only one but also takes more than one person to believe it. The broader scientific community has NOT accepted it. But again, that is part of the scientific process. What you are doing is literally taking film of one punch in a 12 round fight and deciding the whole match on it. The rest of the scientific community obviously did NOT see this as a knock out blow, as witnessed by the open letter from 255 NAS scientist that came out today. -
Rob Honeycutt at 06:31 AM on 8 May 2010Kung-fu Climate
@poptech... I think you should read my previous post again. It wasn't about Mann at all. It was about the public perception of science and the battles that go on that are part of the scientific process. -
Doug Bostrom at 06:19 AM on 8 May 2010Kung-fu Climate
Poptech, for the slow-witted among us, could you explain how Mann's reply to Mc&Mc 2009 is incorrect, in your own words? How is it funny? Tell us in your own words, please. -
Rob Honeycutt at 05:50 AM on 8 May 2010Kung-fu Climate
@poptech... I think what doug's comments point out is the same thing that I'm actually trying to say in my main post above. This IS what scientists do! They challenge each other. They battle. They quarrel. They snipe and sometimes even get unpleasant in their exchanges. That is part and parcel to most science and is particularly true of a contentious issue like global warming. The mistake to make is thinking that Mc&Mc somehow completely invalidate Mann's work. This is the process by which solid scientific theories are built. But what is happening is the broader public out there is being fed details of this robust scientific process and are being told that everything is broken, when in fact it's not. The good fight is extremely important. Science would get nowhere without it. The problem with the public perception of this process has to do with a lot of unfair amateur refereeing going on along at the side lines. -
cdion at 04:50 AM on 8 May 2010University of Queensland talk wrap-up
Nice slides! I have a question. In the notes, you say: "The greenhouse effect operates day and night so this means nights should be warming faster than days." The logic for this escapes me. Why faster warming during the night? -
NewYorkJ at 03:12 AM on 8 May 2010Kung-fu Climate
Ned: "Maybe you're right and the previous commenter was just referring to "why he cannot get any climate change papers published." If that was unclear to me, it was probably unclear to others as well (or, maybe not :-) " I took it to mean "why he cannot get [the stuff he's complaining about] published". Thanks for the link to the E&E discussion. -
Kung-fu Climate
Poptech, Let's assume we toss out the CRU data. Now what? Where does your argument go from there? The remaining datasets all show either the same results or more warming, and most of them do have the raw data and source code available. Your entire line of argument is a red herring. -
Doug Bostrom at 02:45 AM on 8 May 2010Kung-fu Climate
Waiting for acknowledgment by Poptech of Dikran Marsupial's concise and complete explanation of which historical temperature data is available, which is not, the reasons for that. By the way, complaining about supposedly "missing" raw temperature data is akin to complaining that you can't read War and Peace because you can't read the same physical copy of the book I read. Get a copy of the book, read it yourself, draw your own conclusions. My margin notes don't change the book. -
JMurphy at 02:25 AM on 8 May 2010Kung-fu Climate
Humanity Rules quotes CoalGeologist asking : "the presumption that there has to be some other explanation than AGW, because AGW couldn't be true" Humanity Rules then asks : Who is making this presumption? Oh wait I remember, it's the straw man. Do you mean this 'straw man' : Believe it or not, Global Warming is not due to human contribution of Carbon Dioxide (CO2). This in fact is the greatest deception in the history of science. Dr Tim Ball -
michael sweet at 02:04 AM on 8 May 2010Kung-fu Climate
Manns' work in 1998 (with subsequent additions to the present) was detailed and built on the work of others. Loelhe makes many basic errors that were worked out before Mannn even became involved. Since Loehle retains errors that others corrected over 14 years ago, why should he be given a voice at the table with those who are informed about how to do this work? Loelhe may be a good scientist in other areas. He should know that if he comits basic errors and adds nothing to the discussion he will not be able to publish in reputable journals. Scientific journals are not op-ed pages, you need new data or analysis to participate. This paper has neither. -
HumanityRules at 01:52 AM on 8 May 2010Kung-fu Climate
151.chris I don't understand your first point sorry The CPC data is from here (near the bottom of the page) http://www.cpc.noaa.gov/data/indices/ There isn't really much context. Just data. -
HumanityRules at 01:48 AM on 8 May 2010Kung-fu Climate
145.chris Again you confuse a scientist recognising possible limitation in his work with bad work. 147.chris 1207 sounds like a big number. Only six (3 if you're using the screened database) of them cover the SH for the MWP. 6 is a much smaller number. The SH data is sparse. Mann's work covering the MWP is essentially a NH reconstruction. The problem is he and you can't recognise the limitations of his work. Loelhe appears to have that important skill. A question. If Energy and Environment is just a rag for peddling denier propaganda why does Loelhe bother putting all these caveats in his work? -
chris at 01:42 AM on 8 May 2010Kung-fu Climate
HumanityRules at 01:26 AM on 8 May, 2010 HR, you're misrepresenting CoalGeologist by false precis. He said:"That said, the presumption that there has to be some other explanation than AGW, because AGW couldn't be true, is what distinguishes denialism from skepticism."
so it's not a strawman at all. Your plots are nice. Can you give us the link so we can look at them in context? Obviously the OLR is likely to depend on the surface (especially ocean) temperature, and so it isn't surprising if this fluctuates as surface temperature fluctuates. However AGW is about the net imbalance between incoming and outcoming radiation in response to enhanced atmospheric forcing, and its temporal evolution towards a new equilibrium. -
chris at 01:28 AM on 8 May 2010Kung-fu Climate
My last word on the non-science aspects of Dr. Loehle, but something which is odd and perhaps a little sad. This is the extent to which his recent efforts are so diametrically opposed to the sentiments he apparently held 20-odd years ago. He felt so strongly against attempts at political interference in science, and particularly the efforts at "fraud-hunting" and "auditing" that he wrote a letter to Nature on the subject. some excerpts [see Nature (1989) 338, p. 370]:"There is a danger in the controversy over fraud in science of merging the concepts of fraud and error. The call for an audit of scientific papers for error is a symptom of this trend. Fraud such as fabricating data or publishing the work of other's as one's own is of course serious, particularly when it involves assessment of drugs and other medical treatments whwre lives are at stake. But error is an inevitable part of science. The fundamental point is being missed in the current debate...."
and towards the end:"Who will review the error hunters? Who is qualified to punish whom?"
And yet Loehle spends time on a blog where the sort of "auditing" that he decried all those years ago is used to bully and harass scientists. Googling "Craig Loehle fraud", uncovers many examples of his work being used to bolster the efforts of those bellowing "fraud" against science. Dr. Loehle seems to think this is now acceptable. ....how one's views and philosophies can change over the years.... -
HumanityRules at 01:26 AM on 8 May 2010Kung-fu Climate
60.CoalGeologist "the presumption that there has to be some other explanation than AGW, because AGW couldn't be true" Who is making this presumption? Oh wait I remember, it's the straw man. I don't know if this is full filling my duty but I was trawling through the CPC website, as you do, and found this. Again energy rather than atmospheric temperature. If this isn't something other than CO2 affecting energy loss from the earth then I don't know what is. The similarity of SOI and equatorial OLR is amazing.
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Nichol at 01:15 AM on 8 May 2010Kung-fu Climate
Wondering about the error-bars, without intimate knowledge of the various kung-fu techniques.. + There is a basic problem with the above curves: without error bars, how can we know they're not all consistent with e.g. the hocky-stick like curves in the middle? Is there a 'fight' going on between these curves at all, or do they simply agree with the one or two using the largest data sample, the ones most likely to be the most precise? Obviously, one would expect the blue curve with much less data also to have much larger error bars. + The question #2 about local vs global temperature proxies is a serious one. It raises the possibility of systematic errors if you limit yourself to localized datasets. Maybe a better approach towards a global curve would be to take the average of one curve for the northern hemisphere and another for the southern? + could somebody explain what was the reason for avoiding the tree ring data? I only remember reading that there are problems with recent tree-ring data. Is there any understanding of the reason for that? Are recent tree rings affected by recent burning of fossil fuels, or other changes in the air? Or is there any reason to believe that there can be problems with older tree ring data? Does 'tree ring data' consist of anything else than just the width of the rings, e.g. some chemical/isotopic analysis of the wood? If not, does #75 have a good reason to be (properly) skeptic about the meaningfulness of tree ring data? Or are there reasonable ways to estimate the systematic errorbars on tree ring derived data? -
chris at 01:11 AM on 8 May 2010Kung-fu Climate
HumanityRules at 00:52 AM on 8 May, 2010 Mann's recent paleoreconstruction (PNAS 2008, 105, 13252-13257), comprised 1209 records [1,158 annually and 51 decadally-resolved proxy series including tree-ring, marine sediment, speleothem, lacustrine, ice core, coral, and historical documentary series]. I'd say that's not sparse. Each of Mann's series meets criteria of verification with respect to temperature relationship validation, dating, temporal resolution and overall homogenisation criteria. He is clear in the criteria by which his (and his colleagues, of course) paleoreconstructions are appropriately N. hemispheric or global. Contrast that with Lohle's use of poorly validated proxies. The use of proxies with inadequate dating and that have temporal resolution of as poor as one point every 100 years. His pretence that by including a couple of poorly validated S. African and one equatorial Pacific set his 18-proxy reconstruction can be considered a global reconstruction. Loehle could have used many more avaliable proxies [he chose one proxy series out of a whole set of ocean sediment proxies compiled by Kim et al (2004) Quaternary Science Reviews 23, 2141-2154, at least 2 others of which had the temporal resolution and dating validation appropriate for inclusion]. And Mann et al. acknowledge the limitations of their work. All science has limitations. As far as Mann's paleoreconstructions go and Loehle's, I consider one to be science and one to be something else... -
Alexandre at 01:10 AM on 8 May 2010University of Queensland talk wrap-up
Very good slideshow. I downloaded the high-res version to make sure I have my copy. It's hard subject to get through in just a few minutes, and you did it well. One minor comment: when I first heard of the stratospheric cooling, I also understood it via the mental picture of that "blanketing" effect at the troposphere. But I was surprised to find out it's far more complicated than that. The blanket analogy works for the imbalance period, but the cooler stratosphere is the equilibrium state predicted in the models. Even Gavin Schmidt had a hard time expaining it at RealClimate - which is saying a lot. Ramanathan used another mental picture that I found a bit more enlightening: since the temperature increases with altitude in the stratosphere, more CO2 there would mean less heat coming down (thanks to ScienceOfDoom here). -
Byron Smith at 01:08 AM on 8 May 2010University of Queensland talk wrap-up
Thanks John - another great resource! I second the comment above about including ocean acidification in any future and slightly longer presentations. Also, if you think you might start getting more invites to information sessions like this, a short course on public speaking might be useful. I have no idea of your skills in this area, and so don't take this as any kind of attack, but everyone can improve and if you've only done a few talks, then getting a handle on some of the basics could help your verbal communication. This message is too important to have people distracted by irrelevant factors. -
D Kelly O at 01:07 AM on 8 May 2010University of Queensland talk wrap-up
John: Great slideshow, I'll add a link to it on my blog. Ned: I agree with your comment about ..."positive examples of "citizen science". Keep on "obsessing", you have at least 1 supporter! -
Ned at 01:05 AM on 8 May 2010Kung-fu Climate
chris, I don't disagree with anything you say there. I was just reacting to the comment "I can see why he cannot get anything published" and perhaps reading too much into it. CL has published quite a lot in his own field, and in perfectly fine journals. Maybe you're right and the previous commenter was just referring to "why he cannot get any climate change papers published." If that was unclear to me, it was probably unclear to others as well (or, maybe not :-) -
chris at 00:53 AM on 8 May 2010Kung-fu Climate
Ned, I don't normally do this (deviate from the science), but I think it's appropriate to comment more generally on on Loehle's recent publications, since this issue came up in the top article on this thread; i.e.:" What I got from him was that he believes himself to be one of the scientists whose work is blocked from publication for political reasons. And I got that his motivation for this 2007/2008 paper was to point out the "politically motivated" science trying to obscure the MWP by Michael Mann and others. I do not doubt Loehle is genuine in this statement and that he is genuine in his desire to do good science."
(i) "good science". Loehle's reconstruction isn't very good science (see the posts that actually address the science, on this thread). His note in the magazine Energy&Environ. on upper ocean heat content wasn't good science (final sentence "...and it remains possible that the result of the present analysis remains an artifact" - quite so!). His recent misplaced assertions in Atmospheric Environment isn't "good science". We could discuss these poor and unnecessary efforts in case anyone considers that my comments are overly subjective. (ii) "work blocked from publication". Loehle has published around 80 papers largely on various aspects of forest and landscape ecology, environmental impacts on habitats etc. He knows what's required to get decent science into decent journals. Pretty much anything that complies with the basic standards of the scientific method can be published somewhere. If Loehle is being sincere, he needs (it seems to me) to confront the reality that his diversion into climate physics has produced sub-standard analyses that don't make the grade (I personally believe he knows this, and that these recent publicationds aren't actually about science at all). We don't have to beat around the bush on this - Loehle has got his papers published in a magazine (E&E) and elsewhere, and we can see for ourselves what it is that Loehle seemingly considers he should have been allowed to publish in proper journals. -
HumanityRules at 00:52 AM on 8 May 2010Kung-fu Climate
97.chris Ron pointed out in post 87 that Loelhe acknowledges that the data is sparse. Much of the problems you level at Loelhe's work are suffered by Mann. The question might be whether Mann and the IPCC (and you) are prepared to acknowledge the limitations of their work? -
Paul D at 00:47 AM on 8 May 2010University of Queensland talk wrap-up
John I think a comment you make in your PDF notes is key to the skeptical attacks and strategy. You said: "...independent lines of evidence all point to the same result..." For those that understand the issues 'independent lines of evidence' are key to proving something. They are the fingerprints of the big picture. However those same 'independent lines of evidence' are a political gift for those that want to spread doubt and confusion. -
Dikran Marsupial at 00:17 AM on 8 May 2010Kung-fu Climate
Poptech @ 25 asks: "What are the reasons CRU raw data is not publicly available?" Most of it is, from the GCHN repository. The bits that are not are owned by various national met offices and CRU have no legal right to distribute them. They are however available from the national met offices. This has been explained e.g. in Phil Jones' testimony to the house of parliament inquiry, and ought by now to be common knowledge to anyone interested in the debate. The reason CRU can't distribute all of the data is because governments (including that of the UK) insist that national met offices make money from commercial licensing of their data, so that the met offices maximize their value to the tax payer. The reason that the data is not all in the open lies with government policy, not the CRU. However, CRU and the UK met office have been working to get permission from the national met offices to distribute the data, although not all are likely to agree. -
carrot eater at 00:11 AM on 8 May 2010Kung-fu Climate
michael sweet: Loehle's paper attempts to answer the question, what happens if you don't use any tree ring proxies. So it will necessarily have fewer proxies than a paper that does use tree rings. Don't knock it for not having 1000 proxies. Loehle does limit himself though by only using proxies where the original authors also published a calibration. Loehle only accepts temperatures as inputs. Loehle 2007/2008 is a couple steps backward from Moberg 2005, which also attempted to reduce the influence of tree rings. Moberg itself could be improved, but Loehle is worse, yet came out afterwards. So even after the basic errors in the 2007 version were corrected, Loehle 2008 isn't progress upon the existing literature. But I'm still glad that some sceptic bothered to try to make a reconstruction. -
Ned at 23:46 PM on 7 May 2010Kung-fu Climate
Michael Sweet writes: When I examine Loehle's paper I can see why he cannot get anything published. That's a very unfair statement. Loehle has published many papers, primarily on forestry, forest ecology, and related topics, in a variety of well respected journals (i.e., not just E&E). Insofar as there are concerns about anything in this paper, let's discuss those concerns. But let's not make sweeping (and incorrect) statements denigrating his publication record in general. -
James Wight at 23:38 PM on 7 May 2010University of Queensland talk wrap-up
A good summary of the basic science – though it is a shame you had to cut some slides. Have you thought have using the graph on slide 31 in a response to “Deserts are retreating”? Also, just out of interest, where did that temperature graph on slide 4 come from? It doesn’t look much like the usual “hockey team” of reconstructions.Response: It's by Katharine Hayhoe, a climate scientist from Texas. It's constructed from ice core and sediment records, she kindly sent me the raw data so I was able to plot it in a format matching the other graphs. I used it because of its longevity, most of the other hockey stick graphs only go back 1000 to 2000 years. -
Ned at 23:26 PM on 7 May 2010What causes Arctic amplification?
skepticstudent writes: One thing I fail to see in all 30 previous posts on this subject is the fact that in 2008 the temperatures were the third coldest since thermometers were invented in 1775. Are you kidding? 2008 wasn't even close to being that cold. In fact, it was above the average of the past 30 years*, and that 30 year period itself is way warmer than any other period in your 1775-present timeframe! In fact, although 2008 was cooler than some other recent years, in the GISSTEMP record it was the 10th warmest year since the start of the record in 1880! Every year since 2001 is in the top 10. Where on earth did you get the idea that "2008 was the third-coldest year since 1775"? You need to check your sources, and preferably provide references for your claims. * 2008 was warmer than the 1979-2009 average in the RSS, GISS, CRU, and NCDC records. It was slightly cooler than the average in the UAH record. -
michael sweet at 23:02 PM on 7 May 2010Kung-fu Climate
When I examine Loehle's paper I can see why he cannot get anything published. He has a "me too" paper. He is re-examining an issue previously addressed by someone else. He has basic math and other basic errors. He uses only 18 proxies versus Manns over 1,000. He claims global coverage that he does not have. What is added to scientific knowledge by this paper? Nothing. It is a waste of paper. Mann has already carefully covered this topic and Loehle adds nothing useful to Manns' analysis. Scientific journals are not open blogs where anyone gets in. A new paper needs to add to knowledge to get published. Either by adding new data (Loehle does not begin to address the many proxies Mann uses) or by developing a new, better analysis. Loehle has just written a poor opinion piece. Good journals have good papers to publish that advance science. Loehles whinging about his inability to get published shows his lack of understanding about what a paper should contain. -
Ned at 22:41 PM on 7 May 2010University of Queensland talk wrap-up
Okay, I've looked through your slides, and you've really done a good job of covering the main points. I like the fact that you include some graphics that are actually very fundamental but that aren't always shown in these kinds of talks. What would I add if you had more time? Maybe a slide or two about ocean acidification ... it's important to remind people about that, particularly since a lot of proposed geo-engineering "solutions" only address warming, not ocean pH. Also, depending on the audience, it might be nice to include positive examples of "citizen science" (e.g., people verifying the surface temperature trend by independently analyzing the same data used in the four "official" data sets [GISS, CRU, NCDC, JMA] ... yes, I know I've been obsessing about this lately; sorry, I just think what Clear Climate Code, etc. have done is really neat!) A slide about this would probably be appreciated by an audience of engineers or non-academics. What would I trim if you needed to save time? I don't know exactly how much time you spend on each section, but I note a string of 9 slides in the middle that focus on the cryosphere (starting with "glaciers are retreating" and ending with "Arctic sea ice is melting"). If you needed to shorten it up a bit, you might be able to consolidate this topic, though it'd be a shame to not include any of the figures you've got there. All in all, well done!Response: I intentionally left out ocean acidification because the next talker, Ove, was a coral reef researcher with many peer-reviewed papers on the subject. I didn't want to steal his thunder. If I present that talk in the future, if I have more time, I would add more impacts at the end. -
Ned at 21:38 PM on 7 May 2010University of Queensland talk wrap-up
Congratulations, John. I'm going to download your slides and look them over. I wish I were able to go to one of your talks, but unfortunately I'm in the wrong hemisphere :-( John writes: [...] my notes (which I forgot to refer to on the day anyway) [...] Apart from a few hiccups [...] I had trouble fitting all the content into 20 minutes [...] I had to jettison [...] which was a great shame (I have much fondness for those graphics). Mental note: make sure I'm allocated enough time to include my superfluous but pretty graphics next time around. [...] Unfortunately, there was only time for a couple of questions which was a disappointment. [...] Well, I've given many dozens of scientific talks over the past couple of decades and the laments you list above could have described pretty much ... all of them! If those are the worst you can say in retrospect, consider it a great success. (No surprise to anyone here, we've seen ample evidence of what an effective communicator you are.) I hope you'll keep doing these presentations because they're desperately needed.Response: Looking at all those quotes, I really am a glass-half-empty type! :-( -
Ned at 21:25 PM on 7 May 2010Why are there fewer weather stations and what's the effect?
skepticstudent, thanks for your comment. However, I would gently suggest that it's often best to keep one's comments a bit shorter and more focused on one or a few points, rather than trying to include everything at once. (Of course, I say this as someone who has produced more than my share of too-long comments!) In science it's very important to be clear about what the question is that you're addressing. Taking photographs of weather stations could be part of testing the following question: (1) Does weather station X meet the following criteria [...] that we use to define a "good" station? In addition, if you used an appropriate sampling scheme (completely randomized, systematic, stratified random, ...) one could also test the following question: (2) What is the best estimate of the percentage of the weather stations in the US that meet the criteria, and what are the 95% confidence intervals around that estimate? Merely taking photographs, however, does not address the following question: (3) Does the suboptimal siting of individual weather stations have a statistically significant impact on estimates of the regional (or global) temperature trend? Now, Watts has made a lot of assertions that his photos "prove" that there is a problem with the temperature record. But neither he nor any of his colleagues has ever published (on his blog, or in the literature) anything that actually shows that quantitatively. In fact, the only quantitative analyses of Watts's surface station results (by John Van Vliet on various blogs, and by Menne et al. 2010) clearly suggest that the kinds of problems Watts and others have identified don't actually propagate through to the final estimates of temperature trends. Likewise, Watts and D'Aleo pointed to a decline in the numbers of stations, and claimed that this decline (particularly among stations that are high-latitude, high-altitude, and/or rural) is artificially biasing estimates of the global mean temperature trend. But neither Watts nor D'Aleo did any quantitative studies to justify their claims. Once again, when people actually started calculating and quantifying the impact of this, it became quite clear that there's been no significant effect at all -- and in fact, insofar as there is any effect, it's been a slight bias in the opposite direction. In fact, you can actually get a good estimate of the global temperature trend using a very small number of stations. This is because temperature anomalies are spatially autocorrelated over long distances. In a recent analysis, Nick Stokes used only the 61 stations in GHCN that have more than 90 years of data and that are categorized as rural. The results match what you'd get using the full set of stations very closely, though there's clearly much more year-to-year variation in the 61-station version:
FWIW, the entire US including Alaska is less than 2% of the surface area of the Earth. So one could actually calculate an accurate global mean temperature data set using a group of stations that included only a single station within the US.
Of course, more stations is better! But anyone claiming that the decline in the number of stations has a significant effect needs to prove that quantitatively, and all the studies I've seen so far have found exactly the opposite.
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JMurphy at 21:24 PM on 7 May 2010Kung-fu Climate
Someone asked about a list of different types of proxies. Lots can be found at NOAA, inluding climate reconstructions. And did I dream it or did someone actually include a link to the Science [sic] and Public Policy Institute ?
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