The NAS Panel is scheduled to issue its report, "Surface Temperature Reconstructions for the Last 2,000 Years" at 11 a.m. on Thursday. I suspect that many people would expect me to be worried about what the panel will say.
Actually, I’m not worried in the slightest.
Based on presentations to the panel, NAS is in an extremely awkward position if their original intent was to whitewash the situation. If they touch the key questions at all, they have little wiggle room in which to avoid some pretty adverse findings. If they avoid or don’t answer the key questions – some of which are simply reporting on factual situations, then the House committees are going to be pretty mad at them for wasting their time.
Here are some of the key questions where I’ll be looking to see if the NAS Panel provided answers or played dodgeball.
House Committee Questions
The first thing to look for is simply: did the NAS panel answer (a) the questions sent to NAS by the House Science Committee (the Boehlert questions) and/or (b) the questions that had been asked of Mann et al by the House Energy and Commerce Committee (the Barton questions).
Looking for answers to these questions is distinct from checking against the panel terms of reference (which also should be done). In setting up the panel, NAS administrators, presumably up to and including Ralph Ciccerone, played a very tricky game by issuing terms of reference for the panel, which were incomplete relative to both the Boehlert and Barton questions. I thought that this was pretty cute on NAS’ part and "cute" has a habit of backfiring and this could easily happen in this case. For reference, here are excerpts from the two question sets:
I am writing to ask you to empanel a balanced group of scientist to provide Congress with expert guidance on the current scientific consensus on the paleoclimate recod and particularly on the work of Drs. Michael Mann, Raymond Bradley and Malcolm Hughges (the so-called "hockey stick" thesis. The group should, in a clear and concise report issued in a relatively short period of time answer the following questions:
1. …What are the main areas of uncertainty [regarding the temperature record of the last 1000 to 2000 years and how significant are they?
2) … What are the principal scientific criticisms of their [Mann, Bradley and Hughes] work and how significant are they? Has the information needed to replicate their work been available? Have other scientists been able to replicate their work?
5. According to The Wall Street Journal, you have declined to release the exact computer code you used to generate your results. (a) Is this correct? (b) What policy on sharing research and methods do you follow? (c) What is the source of that policy? (d) Provide this exact computer code used to generate your results.
7. The authors McIntyre and McKitrick (Energy & Environment, Vol. 16, No. 1, 2005) report a number of errors and omissions in Mann et. al., 1998. Provide a detailed narrative explanation of these alleged errors and how these may affect the underlying conclusions of the work, including, but not limited to answers to the following questions:
a. Did you run calculations without the bristlecone pine series referenced in the article and, if so, what was the result?
b. Did you or your co-authors calculate temperature reconstructions using the referenced “archived Gaspé tree ring data,” and what were the results?
c. Did you calculate the R2 statistic for the temperature reconstruction, particularly for the 15th Century proxy record calculations and what were the results?
d. What validation statistics did you calculate for the reconstruction prior to 1820, and what were the results?
e. How did you choose particular proxies and proxy series?
This cuteness led to a couple of interesting events in the NAS panel process. Partway through his presentation, Von Storch put up a slide, referring to the Boehlert questions. The panel, including the chairman, was nonplussed as they had never seen the Boehlert questions. There was some discussion as to whether von Storch would even be allowed to present his answers to these questions. The panel indicated little appetite for wading into detailed issues such as data availability, seemingly wanting to spend its time on “big picture” issues. At the end of the first day, a representative of the House Science Committee told them in no uncertain terms that the House Committee wanted answers to specific questions so that these questions could be taken off the table one way or the other; that there would be many more opportunities for big picture reports. Later (March 30) the panel’s terms of reference was amended to require it to comment on data availability, but this was long after presentation day.
If it wanted to, the panel could easily have construed its terms of reference broadly enough so that it actually answered both the Boehlert questions and the Barton questions. I’d be dumbfounded if they gave comprehensive answers to these questions, which will leave the two committees with some interesting choices, if they are still interested in the issues.
Battleground Issues:
Next I’ll do a quick review of "battleground issues" to look for in the NAS panel report.
1) Data Availability
Data availability was one of the original Boehlert questions, that was not represented in the NAS terms of reference and as noted above, was re-added during the process on March 30. In my opinion, the panel does not appear to have discharged this aspect of its mandate very effectively and I’d be astonished if they produce anything other than generalities on this topic. Answering questions about data availability requires detailed work and cannot done by the usual academic fallback technique of a literature review. This is essentially an accounting question. Were actual accountants or business consultants charged with producing an answer, they would have had some staff working on it; the staff would almost certainly have re-interviewed me about data issues, as I’m knowledgeable about them. This didn’t happen, so my surmise is that the panel has simply not done any investigation of data availability and will render mere generalities back to the House committees.
One particular colorful incident in the presentation was when Von Storch repeated the famous Phil Jones quote (which he might have picked up from climateaudit:
We have 25 or so years invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it." (Phil Jones).
Von Storch condemned this attitude of Jones in the strongest possible terms, stating to the committee that “Relevant data and details of algorithms need to be made public even to “adversaries”" Von Storch also advised the committee, in answer to one of the BOehlert questions, that "the [MBH] information required for replication was not made available in a suitable manner.
2) The "Divergence Problem."
The Divergence Problem falls into the category of a “main area of uncertainty” and is something that I’ll be looking for. This issue was not really on the table when presentation day started, but really grew legs during the hearing, long before we got on the stage. It got going when Cuffey noticed that the D’Arrigo et al 2006 proxy reconstruction went down after 1985, despite rising temperatures. He asked D’Arrigo about the discrepancy and she said – That’s the "Divergence Problem”, and thought that she’d answered the question.
The "Divergence Problem" arises because the majority of temperature-sensitive tree ring width "site chronologies" go down in the last half of the 20th century. These ring width chronologies are the “active ingredients” in nearly all 1000-year temperature reconstructions – corals and things like that are just window-dressing. ; however, tree ring widths are not increasing with warm late 20th century temperatures, but are declining. To his credit, Cuffey followed up with the $64 question to D’Arrigo: if tree rings are not picking up late 20th century warmth, how can you be certain that they might not have had a similar response to a comparable warm period in the past (e.g. in the Medieval Warm Period). The responses of D’Arrigo and others at the panel were, to say the least, unsatisfactory. In our PPT presentation, we included a graphic from Briffa et al reinforcing the issue. Cuffey must have emerged very dissatisfied with placing much weight on such reconstructions. It really is an important battleground issue for people seeking to rely on Hockey Team 1000 year "reconstructions". It wasn’t a "battleground issue" when the presentations began, but it became one. IPCC TAR totally dodged the issue. This is an Ohio or Florida – it could go either way. It’s a good one to watch.
3. Verification Statistics
One of the Barton questions shown above is the question to Mann about his verification r2 results. Arguably, this is the question that launched the NAS panel, as , in response to the Barton Committee, NAS wrote to the Barton Committee, specifically mentioning this question as one more suitably answered by the formaiton of an "independent expert panel (according to our standard rigorous study process) to assess the state of scientific knowledge in this area"." Mann’s answers to the Barton Committee on this and the related questions were evasive at best.
During Mann’s presentation, a NAS panelist asked Mann the same question as the Barton Committee – did you calculate the verification r2 statistic and what was the result? Mann replied: "We did not calculate the verification r2 statistic – that would be a foolish and incorrect thing to do". None of the statisticians on the panel tried to pin Mann down on this – a passivity that I found very strange and unsatisfactory. Afterwards, panelist Nychka of UCAR told me that, just because they didn’t say anything, didn’t mean they didn’t notice.
This answer by Mann puts the NAS Panel in a real quandary. The previous day we had discussed this very question and provided conclusive evidence to the committee that Mann did calculate the verification r2 statistic. See relevant section of PDF and PPT
The panel had all this evidence in their hands prior to Mann’s presentation.) So Mann’s bold-faced denial that he had ever calculated the verification r2 is not going to help Mann’s credibility with the committee very much, although it would be surprising if they called a spade a spade. After presentation day, matters got even worse, because Wahl and Ammann’s revision became available. It grudgingly conceded that Mann’s verification r2 was ~0.
The entire issue of verification statistics was a tar baby for them to start with, much complicated by "that would be a solly and incorrect thing to do". There’s simply nothing that they can truthfully say on the matter that does Mann any good. Will they dodge the question totally?
4) Confidence Intervals.
Confidence intervals came up in two different ways. Cuffey asked every presenter whether they could estimate the temperature 1000 years ago to within half a degree. Other than Mann, they all said no. Whether by coincidence or intention, half a degree was the 95% confidence interval of IPCC TAR. I’d be surprised if the NAS panel made the comparison, but others (including me) will.
Confidence intervals also came up in a more technical context. We strongly criticized the Hockey Team methodology of estimating confidence intervals based on calibration period residuals, rather than verification period residuals, and asked the panel to declare against using calibration period residuals. Because Mann’s verification r2 is ~0, confidence intervals using verification period residuals (which are large – hence the negligible r2 statistic) will result in very wide confidence intervals – probably from the "floor to the ceiling" in Hegerl’s phrase. So there are two aspects of confidence intervals to keep an eye on.
5) Bringing the proxies up to date
A relatively non-contentious recommendation could arise here. One of the crazy aspects of proxy reconstructions is the use of so many proxy series ending by 1980, before recent warming (although the “Divergence Problem” might be a factor affecting proxy selection.) Alley made interesting observations about problems in relying on academic institutions and doctoral/post-doc programs for what are essentially “routine” updates. This could catch the Panel’s attention such that they make recommendations to NSF.
6) Cherrypicking
"You need to pick cherries to make cherry pie”, D’Arrigo told an undoubtedly astonished panel, undoubtedly expecting to hear about more sophisticated selection protocols. Ralph Ciccerone of NAS must have winced. Procedures for selecting proxies are one of the big issues in multiproxy studies as current methods seem arbitrary at best and biased at worst. (The use of the HS-shaped Yamal chronology instead of the Polar Urals Update with a high MWP is an example publicized on this site.) The Barton Committee asked Mann et al to describe their selection procedures, but received an unhelpful answer.
In a follow-up to our presentation, we submitted a graph with a high MWP from picking apples instead of cherries – merely to illustrate the impact of arbitrary selections. Just for fun, we included some of Cuffey’s data in the reconstruction.
Ideally one would hope that the panel will turn its attention to proxy selection protocols, but I’m not hopeful of this.
7) dO18 in Ice Cores
Another major uncertainty in proxy interpretation is that some key recent studies (Hoffmann et al., 2003; Vuille and Werner, 2005; Vuille et al., 2005), have attributed dO18 changes in tropical ice cores as being primarily due to changes in precipitation amount, although these series have been interpreted and presented as temperature proxies. The uncertainty of this interpretation needs to be squarely addressed by the panel.
8. Other Uncertainties
It would be nice if the panel listed all the various identified uncertainties with proxies: non-normality (especially with Moberg) and its impacts; for tree rings, altitude changes, "modern sample bias", etc.
So I’ll be looking for all these issues and more. What if the NAS Panel avoids all or most of the contentious issues and simply produces IPCC Lite? Or if it produces a "two-handed report" – on the one hand, … on the other hand,… (as rumors suggest)? This would re-open the door for the House committees and be rather an embarrassment for the Boehlert committee, which sponsored the NAS panel, and also raise questions about how NAS selected specialties to be represented on the panel.
If this happens, then NAS itself should answer some questions about panel composition. We pointed out the absence of replication specialists, the absence of statisticians with exactly appropriate sub-speciality expertise (the two statistical panelists being more frerquency-domain types).
References:
WSJ l including the wonderful Mann quotatoin: "Giving them the algorithm would be giving in to the intimidation tactics that these people are engaged in," he says.
Barton Letters
MBH Responses
Ciccerone, R., 2005. Letter to House Energy and Commerce Committee, July 15, 2005.
NAS Project http://www8.nationalacademies.org/cp/projectview.aspx?key=BASC-U-06-01-A
Boehlert Questions
M&M Presentation to NAS Panel PPT
M&M Followup to NAS Panel
Climate Audit 
121 Comments
This is a great post. Much more tightly organized than your typical. Reads as if you put specific effort into it, perhaps thinking that NAS would read this? But the report is written, no?
Re #1 It’s probably a “watch the pea under the thimble” post. I’ve no doubt that short of a “throw Mann into the deepest darkest hole”, the Hockey Team will claim victory, that they’ve been “vindicated” and that the criticism of McIntyre and McKitrick have been “definitively refuted by an expert Panel”
Never forget the Hockey Team’s greatest scientific ability: spin. Lots of spin.
Steve:
I wanted to reiterate my feelings on the M&M Powerpoint and follow up presentations.
I thought they were outstanding in a variety of regards. In addition to addressing key potential NAS panel issues, they also served as excellent primers on several topics, and neatly summarized the relevant debate on other topics.
WRT embarassing the Boehlert committee, they may not feel that to be too risky, now that Boehlert will be leaving the House at the end of the year.
Superb analysis!
Following the story in the mass media (MM) was impossible. I was unaware such an important report was due today.
I know how the results will be handled in the MM: trumpet any findings which support GW; and, igore everything else.
John
It will be fascinating to see how this reads then plays out. A two-handed report? I would have thought that this brings Sen. Barton & co back onto the field of play. Why am I reminded of the final game in the film Slapshot?
Of course, the next question is what is happening with the team of statisticians that Rep. Barton has got working on this issue ?
Steve, I think you and the Representative are up against an old-boy club, and in my experience there are few groups as viscous as academics. They defend their own.
What I, and think everyone, want to see is the truth, whatever that truth is. If the truth supports Mann, fantastic. If the truth refutes Mann, fantastic.
What I think we’ll see, though, will be smoke, mirrors, red herrings, some valid points, side roads to nowhere and some dead wrong points, weaved together in ways that will be almost impossible to untangle. The goal is to answer nothing and tire readers out, so that the questions die. If the Democrats take control this fall, then the probe will likely fade away.
I am sorry to be so cynical, and I hope I am dead wrong, but I certainly would not get my hopes up that questions will be answered.
The links in this article didn’t work for me. These modified links did work:
Click to access NAS.M&M.pdf
http://data.climateaudit.org/pdf/NAS.M&M.ppt
Thanks
JK
I’m new here, so apologies in advance for any dumb questions.
I would like to know whether Steve McIntyre’s work is restricted to finding flaws in MBH98 or whether it has wider implications for the scientific consensus on global warming. In his “A few inconvenient truths” post Mr McIntyre agrees that CO2 is building up in the atmosphere and that “the impact of 2xCO2 is a large and important issue”. However, he also says “Extrapolating from the lack of due diligence in the hockey-stick arguments, I am concerned about the level of verification and due diligence in these other areas, but perhaps it’s different”.
How can you extrapolate the (possible) carelessness of one group of climate scientists to other climate scientists? Are you suggesting that interpretation of other evidence (ice cores etc) are similarly flawed? And if so, why?
So, I am interested in Boehlert’s third question (not repeated above):
In other words, if Mann et al are wrong, does it matter?
The answers in the M&M PPT presentation were:
The first and second points are PR issues that don’t really change the science. They might change public opinion and policy but not the science. The third and fourth points are more troubling. Can you please be more specific about how the methods used in MBH98 have affected later studies?
One of the Boehlert questions was: “Have other scientists been able to replicate their work?” During the comment period on composition of the NAS panel, we suggested that they include a replication specialist – needless to say, NAS ignored this and several other suggestions about panel composition (e.g. adding someone with statistical expertise that related to our point of view on the questions and removing people who were associated with Mann or Ammann.) If the NAS Panel touches on this question, it will be interesting to watch what they consider as “replication” – and here the lack of a specialist is frustrating. For example, consider the following “replication” alternatives:
1. Replication of MBH claims of statistical skill (RE, r and r2 being mentioned in MBH98) and MBH claims of robustness to the presence/absence of all dendroclimatic proxies. These are really the issues that launched the inquiry. Boehlert’s question: “Have other scientists been able to replicate their work?” includes this. This is a very empirical question. If I were a policy maker consulting NAS, I’d expect them to answer this. The answer to this question is, of course: no. Even Wahl and Ammann reported a verification r2 of ~0 as we also reported. Will the panel report on replication of the above two MBH claims? If it’s a two-handed report, then they’ve not answered the question. This is a one-handed question.
2. Replication of MBH99 confidence interval calculations. No one’s been able to replicate them. This was explicitly stated on presentation day by both von Storch and ourselves. MBH98 calculations can be “replicated” – two-sigma on calibration period residuals – but can hardly be endorsed.
3. Replication of the MBH98 hockey stick to 2 decimal places using reported methods. Expressed this way, the answer is again no. Some aspects of MBH can be replicated in their major features. In this respect, Wahl and Ammann did nothing that we had not already done and I’ll be cross at the panel if they attribute any replication to Wahl and Ammann without emphasizing that we had done the same, but drew different conclusions. Wahl and Ammann, like us, were able to replicate a HS, but not the MBH HS to 2-digit accuracy. The remaining anomalies are puzzling and were what I was referring to in the WSJ quote. I’ve got about 90% of the crossword puzzle done and it bugs me that I can’t finish it. There’s nothing in Wahl and Ammann that deals with this last 10% of the crossword puzzle. But what’s going on here? It’s sometimes amazing what happens when you pull on little loose ends of string. As to replicating things like Mann’s retention schedule for PCs (Preisendorfer’s Rule N applied to all networks doesn’t work), Wahl and Ammann didn’t even try to replicate these choices, but simply parameterized the MBH schedule.
4. Replication of a generic spaghetti squiggle in which the MWP proxy index is lower than the modern proxy index, together with lower values in the 17th century. That’s probably what we’ll hear about. Will they discuss the non-independence of these spaghetti squiggles? For example, readers of this blog know that the relative MWP-modern relationship in many of these squiggles is not robust to whether the Yamal Substitution or Polar Urals Update is used. Will this be reported by the NAS panel? You could blow me over with a feather if they report this.
#10. The other Boehlert question is a good question. I’ve discussed this as well in the past (see my Op Ed at Roger Pielke’s blog for example. One comment on due diligence – I’m not talking here about the "carelessness" of a group of scientists, but reliance on what are essentially "unaudited" results. Other groups may not have been comparably "careless", but their results are still "unaudited". Peer review at journals is a very limited form of due diligence. Something additional is needed.
Secondly, you make a distinction between "PR claims" and "science". I sometimes compare what I do to being a pre-Iraq War analyst considering aluminum tubes who says – you know, sometimes an aluminum tube is just an aluminum tube and not evidence of WMD. Just analyzing the aluminum tubes doesn’t in itself disprove all WMD issues or even necessarily bear on the grounds for war. But it means that those other grounds have to be themselves analyzed closely.
Within the little world of 1000 year multiproxy studies, every subsequent study refers to MBH and is influenced by it. Many of them have a knife-edge balance between the MWP index and the modern index – just enough to say that the modern index is the highest in 1000 years, but very vulnerable to very slight accounting problems.
MBH and similar HS shapes appear to have influence attribution studies, where I’m less familiar with the nuts and bolts. (Although a major mis-representation in the attribution section of MBH98 has recently been identified in blogworld, which wasn’t available to the NAS panel.) So if the HS studies fall, you have to re-examine all the detection and attribution studies relying on proxy results and independently assess the extent of the potential damage.
As to the “larger” issue, one could reasonably decide that the HS argument was fatally flawed without necessarily concluding (a) that the MWP was warmer than present i.e. the issue was open; (b) that other arguments for being concerned about potential AGW were flawed. I don’t think that you could reasonably conclude that the HS was flawed (especially in the way that the MBH HS is flawed) without also concluding that the “self-correcting” processes were in this case singularly inefficient and let a lot of people down.
Steve and I discussed the “what-to-watch-for” issues over the phone on Monday night, heavily distracted by the Oilers-v-Hurricane final. The write-up above is a very good summary of those points, but Steve has also neatly brought out the issue that competing sets of questions stood behind the NAS panel. It’s important to understand that at the time of the meeting, the sets of questions did not coexist on the floor. After von Storch surprised everyone with Boehlert’s questions, it was our turn to speak. We also turned to the Boehlert questions, at which point the chair interrupted, and there followed a little sidebar over whether we should address these questions since they weren’t in the NAS terms of reference. It was agreed that we could briefly present answers to those questions but not dwell on them, and instead focus on the NAS issues. So even if the terms were revised later, on the day of the panel itself they did not gather input on the Boehlert questions, except reluctantly and, apparently, without the intention of delivering answers to them. So it would be very odd if the NAS report tomorrow actually attempts to answer the Boehlert questions.
As for not being nervous, I’ll admit to feeling some apprehension. I’m not concerned about the substance of our arguments or the soundness of the conclusions we presented. But whether they get reflected in the report is another matter. Any panel can get caught by tunnel vision, political correctness, wagon-circling and other such instincts, and if the opening line of the executive summary spins even slightly in favour of the hockey team then a lot of journalists won’t read any further.
The timing of the release is unfortunate for me as I’m about to hit the road for a couple of days to a conference, with limited internet access the rest of the week.
David,
Assuming, for the sake of argument, that the earth is warming, one then must ask: is this a problem? We know that climate is not static, so what we need to determine is whether the current trend is unusual. So the core question becomes: what is the normal climatic global temperature variation? If we can’t answer this question with a high degree of certainty and precision, all the talk about GHGs, greenhouse effects, etc. don’t really matter much as far as public policy is concerned. All these past temperature reconstructions are attempting to answer this core question. Currently Mann and his small circle of followers/friends have produced a number of studies that indicate that the current warming IS out of the norm and policy decisions affecting billions of people and trillions of dollars are being made on that basis. But what if Mann and his cohorts are wrong? What if their science is sloppy and unsupportable? How can we even know if we don’t/can’t go over these studies with a fine-toothed comb?
So much turns on the answer to this core question. We have to get it right.
“”Within the little world of 1000 year multiproxy studies, every subsequent study refers to MBH and is influenced by it””
And here in the US (or California where I live) it also influences our childrens science classes (they are required to inform the children, and not necessarily even discuss it!), it influences the EPA , the governor Arnold, all regulations and our pockets and purses, every environmental organization I can think of, and even influences in the risk assessments of production of materials (like foam or even devices like incubaters, or lazers)..anything that refers to CO2.
I can’t even begin to tell you Steve and Ross how I appreciate your work.
Use the Force Luke!!
Cheers!
#10 3rd&4th questions: if you follow the sidebar link on ‘other multiproxy studies’ or wordsearch on Spaghetti Graphs you’ll find discussions of how the MBH work has become a benchmark for other results, and in some cases (like Osborne and Briffa’s paper) they re-use the outputs of the MBH PC procedure as an input to their own. In the signal detection literature, the regression variables are rescaled using (GCM) model-generated estimates of natural variability. To the extent modelers have one eye fixed on pre-industrial paleoclimate reconstructions to judge the GCM natural variability outputs, MBH will be influential there as well, even when not directly cited. Some of the paleo papers include simple signal detection exercizes, including MBH98 itself as well as work by Crowley and Hegerl.
The 1st 2 questions can’t be so lightly dismissed as mere PR. The IPCC boasts that its reports represent a scientific consensus, based on journal peer review and expert panel peer review. If a paper appeared in Nature, was selected for lavish highlighting in the IPCC report and has been heavily cited in subsequent expert literature, but it turns out to be fundamentally unsound, then that’s not just a PR problem.
RE: #15 – In many ways, we here in California are already getting a strong taste of what the rest of the world may face, if, instead of answering all of the above questions (as well as a number of other, purely scientific ones) we globally rush headlong into tactics and actions based on the presumption that the future according to Mann et al is a reasonable representation. There are indications that the “low carb(on)” system we are putting in place may have unintended consequences. Even in Europe, there are things that await, that we are already well into – for example, a power grid mainly reliant on natural gas and hydroelectricity, topped off by wind power and only a miniscule nuclear component (Germany is evolving to be the closest to this model). The hybrid craze has taken off and as a result, there is little incentive to actually work on things like efficiency in classical gasoline only cars or bio diesel. Taxation wise, we are on the verge of layering a carbon tax on top of an already heavy tax burden – when all is added up, between our federal, state, property and various sales / VAT levies, we actually pay out at rates comparable to France or Austria. With the added carbon tax, we’ll lead the free world in terms of tax burden. This is going to be interesting.
Re #10, David Michie
Two points on the “scientific consensus on global warming”
Before MBH98 came along, the scientific consensus was that there was a global Mediaeval Warm Period when temperatures were warmer than today. This could be seen in a chart in the first IPCC report. Mann’s hockey stick was a significant move away from that consensus. From the problems M&M have had, it is pretty clear that there has not been any widespread checking of the MBH98 results, to justify that change in consensus.
More generally, I think that the majority of scientists tend to be fairly specialised in their own field. I suspect that most working scientists probably do not have any better understanding of the statistical details of multiproxy reconstructions than does the average intelligent person watching the news. When the spin doctors go on about “most scientists accept that global warming is real”, that does not mean that the scientists have looked into this work and confirmed that it is valid. Rather, it means that they haven’t had any reason to look at it, and they assume that the climatology field has been keeping its own house in order.
On your question :
In other words, if Mann et al are wrong, does it matter?
There is (or was) a post somewhere on RealClimate called “What if the hockey stick is broken”. After a lot of faffing around, they came to the conclusion that it wouldn’t matter, because the computer models say the same thing. So I guess it depends on whether you take the models seriously, because even the hockey team can’t find any other real evidence.
Re #17, Steve Sadlov
Forgive my ignorance, but are there any specific pubilc sector subsidies for hybrids ?
#17, I read not too long ago that Cal EPA is now imposing fines on California wine growers too. I totally think it’s a good idea to lower emmissons and find alternative fuels (lots and lots of reasons for it) but to fine a winery for production practices that 15-20 years (even maybe for 100yrs?) ago were perfectly fine; seems unfair and again another excuse for EPA get funded so they can continue to be the EPA. LOL
I also consider things like: let’s see, take China, If China would just adopt practices like our basic EPA regulations outlined for along time now; my husband says you could say that the giant smog cloud over China; would considerably shrink in ten yrs or less, or even be gone. He finds in his work all the time how fast things “clean up” and bounce back when you jump in and do it. The main stream media and the eco-groovy types never seem to provide that part of the senerio, just all gloom and doom.
BTW, I make this clear:
I do believe it is important to take care of the earth.
(apologies, I can’t form good sentences for the life of me today!)
I think one of the most important issues to focus on is the intentional, unsupportable, unexplained, unabashed, unscientific cherry picking that was necessary to demonstrate a temperature signal from tree rings. This issue, alone, renders all these Hockey Stick studies as junk science.
Wonder if anyone has done a Life Cycle Analysis of hybrids. A hell of a lot of CO2 and a lot of pollution goes into making batteries.
I, too, look for a weasel-worded “two-handed” report from NAS. They are stuck in a real connundrum here. It would be very politically incorrect for them to just speak straightforward to the science, like they should. And isn’t that a terrible reflection on this society?
RE: #19 – I am unsure about any direct subsidies. However, certainly, since a single driver in a hybrid is allowed to use the HOV lanes during peak commute times, that is certainly a perq. There may be a tax credit as well, I just don’t know for sure. I think the things driving people to buy them, even given the questionable ROI (I think gasoline would have to consistently exceed $4 per US gallon) are firstly environmentalist leanings and secondly the HOV lane single driver exemption. There is even a cute little sticker you put on your bumper to keep the CHP from bothering ….
IMHO, whether the committee takes issue with Mann per se is of less importance than what they say about Steve’s (and Ross’) work. If the panel finds that Steve and Ross are correct on even one substantive issue, this will lend credibility to their ongoing efforts. It is hard to imagine how the panel could reject every argument, no matter what (if any) predispositions the individual members may have. But, we shall see.
There are tax credits for using many “environmentally friendly” technologies. This list includes vehicles as well as solar power for your home. There’s a special section in TurboTax for these, btw.
The RC fans that have decided that the hockey stick “does not matter” are fooling themselves twice. First, they’re rationalizing their own bad science based on a somewhat circular argument. I.e.: it must be right because the climate models agree! In order to verify the model, you need something to compare to, which is often the hockey sticks themselves. Unfortunately, the climate models suffer not so much from bad science as incomplete science, particularly w.r.t. cloud formation. This does not even touch on other variables that are either poorly understood, or flat out improperly implemented.
Mark
Re #s 18 and 26: In addition to the models, there is the slight matter of the numerous direct observations of climate change. Funny that neither of you mentioned those.
#27 – but Steve B, isn’t that an answer to to a different question?
The issue is whether there is sufficient confidence to be able to hindcast using proxies. What the NAS panel testimonies has suggested to me is that the answer to this particular question is no. The consequence of such an answer is that it muddies the water a little more. Sure there is observational evidence of a warming in the last 30 years but there is little to hang your hat on as regards showing it as extraordinary.
To me, if the report does turn out to be two-handed then all it invites (as I suggested earlier) is a larger fight without much hope of anything constructive coming out of it.
#27 — There is also the slight matter that in the absence of a falsifiably predictive climate theory, the on-going climate changes are indistinguishable from normal variation. Funny that this basic standard of science has consistently evaded your grasp.
The Boehlert and Barton questions are much like if you were directly dictating them, which is of course making them look good. 😉 If they constructed them using a different method than by directly reading and copying a text of yours, then I must say that for politicians, these guys seem pretty skillful in science.
This criticism of cherrypicking from the biggest group of cherrypickers and liars on the face of the planet.
CO2 = Life? Try this:
http://www.outsidethetent.com/wp/archives/the-new-cei-print-ad/
# 29 – “the on-going climate changes are indistinguishable from normal variation”. How do you know this to be true?
29:
There is also the slight matter that in the absence of a falsifiably predictive climate theory, the on-going climate changes are indistinguishable from normal variation. Funny that this basic standard of science has consistently evaded your grasp.
The falsification of your little hypothesis would include the need to eliminate the CO2 ppmv level to show normal variation. When the denialists create a model that details this separation, let us know.
Best,
D
Re: 31
The relevance of your comment to the presentations by Steve and Ross to the NAS panel has eluded me. Are you able to identify a substantive error Steve or Ross has made?
Regards;
Does it surprise anyone that on this day so many warmers show up who haven’t been around for quite a while. I wonder if they’re all nervous?
Has anyone seen the House Report yet?
any chance of a Drudge Report style (ahead of public release) release of the report?
re #27
I think you just proved my point. AGW adherents assume “climate change” as if there is some inherently stable climate with which to compare. It is a chaotic system that always changes. That we should observe such changes is a no-brainer.
That the climate is in a constant state of flux is beside the point. The point is that using models and proxies we are still not able to predict such changes, let alone attribute them to any specific cause other than normal variation.
Mark
Oops, instead of “AGW adherents assume” I should have said “AGW adherents speak of.
re: #31, I’m not sure what your alarmist advertisement is supposed to prove? Tacked on with insults, your continued ability to post is questionable.
re: #32,
Read the site. Steve and Ross have all but proven that the proxy results are indistinguishable from normal statistical variability.
Mark
I think this could be quite amusing. As you point out, the energy committee asked some very specific questions, and was immediately bawled out by the science committee, who claimed it was their turf… The energy committee have accepted that, and they have given the matter over to science committee. If it turns out that the science committee has commisioned a report that doesn’t answer the barton questions, and doesn’t even answer the questions that the science committee set, then that will be hilarious.
Specifically, question 2 has some concrete questions that can be answered simply and definitively, and it would be astonishing if these issues get swept under the carpet by the energy and science committees. One could even imagine that the energy committee could quite enjoy pointing out the inadequacy of their sister committee 🙂
yours
per
Re #32, Nick
You need to read Pat’s whole sentence. The clause you quote is not a stand-alone assertion.
Re #33, Dano
You need to … oh, never mind.
Re #38: Let’s see: Nobody predicted overall warming (oceans and atmosphere), nobody predicted excess warming in the Arctic, nobody predicted longer growing seasons, nobody predicted more tropical cyclone activity, nobody predicted stratospheric cooling, nobody predicted increasing drought, etc., etc. That nobody is quite the paragon of scientific acumen!
35:
Does it surprise anyone that on this day so many warmers show up who haven’t been around for quite a while…
Somebody linked here today talking about the high amusement value. It’s easy to click on a link.
38:
AGW adherents assume “climate change” as if there is some inherently stable climate with which to compare.
No they don’t. That some folks think past climate was stable is a constructed narrative that denialist rubes choose to believe.
and
The point is that using models…we are still not able to predict such changes…
You’ve been to the fyoocher to see whether they’ve verified? Coooooool.
Can you tell me the winning PowerBall numbers next week? I’ll give you a 15% cut. OK, 20% but that’s my final offer.
Ahhhh…thank you all, lads – you’re great today.
Best,
D
Uh, Steve Bloom’s comment alone is enough evidence to support that thesis, particularly since I was replying directly to his comment. He quite clearly stated that “evidence of climate change is all around us”. No kidding.
And exactly how is a random process evidence of YOUR thesis? Really now… this analogy is absurd. AGW adherents are attempting to predict the PowerBall outcome (analogously) if you haven’t noticed. That’s MY point.
Mark
re: #42
Uh, it cooled from about 1930 till the mid 70s, the antarctic is actually cooling, cycloe activity for the planet has been consistent with a drop in Pacific and an increase in the Atlantic, statospheric “cooling” is not as much as predicted and finally, sorry, but droughts happen all the time.
Mark
Oh, yeah, and every major hurricane center the US has stated repeatedly that the increase in the Atlantic is due to a multi-decadal cycle for which we are now seeing a peak. That we have only been able to reliably track hurricanes for 30 years or so must not matter, eh?
Mark
My outcome prediction?
“Send more money.”
Help me stereotype me. I’d like to know my label:
1. I believe, firmly, that the increase in atmospheric CO2 has, and is, raising the planet’s temperature to a value higher than it would otherwise be.
2. If I was forced to guess the magnitude, I would guess it will be about what CO2 alone would cause, without positive feedback involving water in its various forms. I think that is about a 2F rise for a doubling of CO2.
3. I believe mankind has been adjusting to climate change throughout our history, and can cope with this magnitude of rise. I believe that an abrupt reduction in carbon use would do social damage of a greater magnitude than that caused by the 2F temperature rise.
4.I believe that, even with a manageable temperature rise, we should be aggressively looking for alternate energy sources and conservation, regardless of greenhouse concerns.
So, what label applies to me? I need to know, so that I can tell when I’m being slimed, insulted, mischaracterized, dissed and/or ridiculed!!
Thanks
Re #s 45 and 46: Mark, the denialist web sites don’t cover the science comprehensively or make any effort to stay up to date, so relying on them for your talking points will always tend to make you look a little foolish.
Hurricanes: See here and here. Note that what’s being seen so far is an increase in strength, not numbers (although of course the Atlantic basin is getting both in spades). BTW, could you provide me with a link to a study demonstrating that a natural climate cycle substantially drives hurricane activity in the Atlantic?
Drought: See here.
Stratosphere temperature: See here.
Mid-century cooling (aerosols): See here.
Antarctic: See here.
Happy reading. For your response, if any, actual up-to-date peer-reviewed citations would be appreciated.
I’m not expecting a brutal assessment (like what Feynman did to NASA after shuttle crash). But I think they will sound some significant cautionary notes. The RC lightweights may spin the note of defense of their clique, but I think in the end, the process is underway to fix the bad science and that this report will facilitate that readjustment.
RE: #49. I sure hope you are correct. This would be my own modest hope as well.
Re #48, David Smith
If you insist.
I would call you a generally sensible fellow, who needs to think about energy storage rather than energy sources.
Re #49: “Lightweights”? Try reading some of the CVs.
Dave S,
Sounds like you’re right in line with most of the skeptics here. There are some ‘extremist’ skeptics who don’t think there will be any temperature rise. I’m not one of them. Though I do have doubts about how accurate the measured surface temperatures are since those who’ve been massaging the data won’t release what they’ve done and it appears they basically ignore changes in UHI. But that doesn’t mean there hasn’t been and won’t be some temperature increase.
Some warmers here tend the same way but buy into the ‘precautionary principle’ and this can drive them off the deep end.
Other warmers (though not necessarily many here) are just plain crazy, IMO.
44:
Sigh…
Steve Bloom’s comment alone is enough evidence to support that thesis
It would help if you could present a statement of his that says ‘past climate was stable’, instead of filling in what you want him to say to gain some sort of rhetorical advantage. Otherwise it looks like you are constructing a strawman. I’m sure you aren’t doing that, right?
It would help more, though, if you could show how others say this too. Especially scientists. Yeah, scientists. It would help your case a lot if you could trot out a few current climate scientists who show this (you know, people who do climatey stuff for a living).
I’ll wait patiently.
And exactly how is a random process evidence of YOUR thesis? Really now… this analogy is absurd.
No, you claimed, without evidence, that models and proxies [are unable] to predict such changes , by which presumably you meant that current models can’t show past climate changes. This is, of course, utterly wrong, but you are obviously correct since you comment on this site, so you must mean that the current models cannot verify into the future.
Since you know this, see, it must mean you have traveled into the fyoocher, and I want those PowerBall numbers and I’ll pay you for them. After all, what person in their right mind would travel into the future and not bring back winning lottery numbers?
Really now…
Best,
D
#32 – The only way to distinguish normal variation from human caused climate variation is to have a physical theory that is adequate to model climate to the necessary accuracy in energy flux. In this case, that accuracy is less than 4 W/m^2. No such physical model exists.
#33, wrong Dano. One can never prove a negative, as you’d have it. You and folks like you are asserting a positive causative claim in the absence of a good predictive physical theory. That’s not doing science. That’s doing mythology. And we can live without your pejorative “denialist” labelling. Most people here have argued the science. That’s not denialism (a meta-philosophy), that’s science-based skepticism. On the other hand, your position is not science-based, but an inductive inference. What shall we call your crew, therefore? Chickenlittleists, perhaps?
#42 – You’re right, Steve B., no one predicted those observables on the basis of a falsifiable physical theory. Do you understand the need for that context, or not? Predictions themselves are a dime-a-dozen. Falsifiable predictions are tough to make, in contrast. They’re the only ones that have scientific meaning. And it is science we’re interested in here. Isn’t it.
The request that science adhere to scientific method is not unreasonable.
By subjecting the theory and models of anthropogenic climate change to the rigors of independent, critical review, the theory and models may be refined to more accurately reflect reality.
Thank you all for replying to my questions in #10, especially Steve in his last paragraph of #12.
AGW is obviously an emotional debate, and what I find disturbing about both this blog and RealClimate.org is the childish sniping and cheerleading that goes on. The constant accusations of someone being an “oil company shill” or someone “coming up with the right result to justify their funding” is also a concern. AFAICT M&M are not trying to disprove AGW, but this blog attracts plenty of cheerleaders from the anti-AGW crowd, just as RealCimate attracts cheerleaders from the pro-AGW crowd. If you’re someone like me (or like David Smith #48) who is just trying to cut through the politics and understand the science, this is extremely disappointing.
I believe that the questions being asked by M&M about the work of MBH are important, and it is important for the credibility of climate science that these questions are answered as openly and transparently as possible. However, even if the NAS panel concludes that the work of MBH is flawed I don’t see that it necessarily follows that AGW is somehow “wrong” and that the work of other climate scientists is flawed.
I would like to know what are the areas of agreement between the pro and anti AGW camps:
1. Do you agree that the level of CO2 in the atmosphere is higher than it has been for at least 400,000 years? (as suggested by ice core studies)
2. Do you agree that the level of CO2 in the atmosphere is rising faster than it has for at least 400,000 years?
3. Do you agree that in all likelihood CO2 levels will reach at least 550ppm by 2100? (roughly twice the highest level of CO2 observed for 400,000 years)
4. Do you agree that much of the observed increase in CO2 is as a result of human activity? (as is suggested by studies of carbon isotopes)
If all four points are correct, regardless of whether the “hockey stick” is right or not, this is surely a matter of serious concern.
Bloom:
I got a flashy CV too. Maybe more so (in some ways) than those dudes. Certainly, I have the union card. I mean, if you don’t have that, you’re scum. Steve, should kiss my ass for even talking to him.
Seriously, though, they have ok ac creds, but I’m used to that. I judge your game, by how you bring it on the playground, not what your Opie coach back home says. Just look at those guys. No game, no heart, no balls.*
*The anti-taunting criteria does not apply to me as I am the pet. You however, should behave.
Pat: au contraire, mon frere. See my highlighted post for another approach to comparing recent and historic variability using statistics (VS06).
Dave M: good post.
David Michie:
I don’t know the answer to those questions but I noticed they are all relating to CO2 content in the atmosphere only.
For me to be concerned about that, I would have to also be convinced that CO2 in those sorts of concentrations (550ppm) is going to cause some kind of a problem. Isn’t that also something you should be looking in to? Of all your questions, the only one I think I know the answer to is #3 and I think the answer is yes. But I still don’t see why that is a cause for concern. Can you explain what makes you think it is? CO2 is certainly not toxic at 550ppm, and as far as I can tell nobody can really agree on what effect it will have on temperature, so perhaps that’s an area that should receive more attention. That’s not a matter that M&M get into per se but others are certainly looking into it I think.
Re # 57. The first 2 points are agreeable. Then you diverge. The third point is based on models which are not perfect. What we have are two similar graphs – one of the temperature increasing and the other of CO2 increasing. There is a statistical association linking the two together. What we do not have is enough scientific proof of what is causing the increase in either or the percentage of the increase attributable to natural variation or man-made sources. Can anyone quote a definitive paper on this? One problem is that some scientists do not want to consider water vapour as a Greenhouse gas.
Are they looking at an increase in pollution and condensation nuclei as a possible source of an increase in cloud which is keeping the minimum temperatures higher?
Re # 57: “If all four points are correct, regardless of whether the “hockey stick” is right or not, this is surely a matter of serious concern.”
I believe a 2F rise in temperature and a rise of CO2 to 550 ppm will be an amazing boon to most life on the planet. It will cause an explosion of growth allowing the earth more than capable of supporting human civilization far more populous and consuming than todays.
Something wonderful is going to happen and nothing the AGW crowd does will stop it.
Question: what is the best way to access the NSF report tomorrow?
How much temp increase do we need to get gators in Richmond?
re #57
“If all four points are correct, regardless of whether the “hockey stick” is right or not, this is surely a matter of serious concern.”
re #64
“I believe a 2F rise in temperature and a rise of CO2 to 550 ppm will be an amazing boon to most life on the planet. It will cause an explosion of growth allowing the earth more than capable of supporting human civilization far more populous and consuming than todays.”
If one considers the fact that the observed warming is concentrated in the winter, high latitudes (and at night) #64 seems to be closer to the truth.
http://data.giss.nasa.gov/cgi-bin/cdrar/do_SCmap.py
Why so little discussion of the twin benefits of rising CO2 and rising high latitude winter temps – more food production.
Re: #62. I think it is beyond doubt that CO2 is a greenhouse gas. I believe that CO2 that represents anywhere between 2% and 26% of the Earth’s greenhouse effect (depending on who you believe). I understand that the greenhouse effect warms the Earth’s surface by ~33C. Even if you take the extreme low end of the CO2-effect range, my back-of-the-enevelope calculation suggests that a doubling of CO2 could raise the temperature by 2% of 33C = 0.66C. If the high end is accurate (26% of 33C = 8.6C) the consequences are serious. The point is, no-one knows exactly what the effect of doubling CO2 will be, but its a hell of an experiment to be running on the planet. As Steve McIntyre says: “the impact of 2xCO2 is a large and important issue”
Re: #56. I think it is beyond doubt that there is a correlation between CO2 and temperature going back at least 400,000 years. There seems to be some doubt about whether increasing CO2 leads temperature rises or vice versa, but the correlation is real. I understand that changes in the ratio of carbon isotopes in the atmosphere suggest that increasing amounts of CO2 are due to human activity.
As I understand it the water vapor argument is not valid. The consensus seems to be that water vapor is a feedback not a forcing. Note Steve McIntyre’s comment in the “A few inconvenient truths” post:
I don’t get this point at all. So what? I think that there are important and interesting issues about negative feedbacks associated with water vapor, as well as the more publicized positive feedbacks. I don’t see the purpose of exchanging soundbites of this type.
I want a drudge report, right farking now!
Sorry, at the start of the second paragraph in #68, that should have been Re: #63 not Re: #56
re $68
David,
My understanding is that doubling CO2 does not double its contribution to temp increase. In fact temp ~ ln (CO2) not temp ~ CO2.
Your best evidence is the data of the last 100 yrs. One can predict with considerable confidence that a future increase in CO2 over the next 100yrs of the magnitude we have seen the last 100 yrs will result in less warming than we have seen the last 100yrs.
#49
Hi Steve B.
Here is a chance for you to increase your credibility (at least with me).
First an easy one. You cite to RealClimate in your post #49. Do you consider all of their posts authorative (so that a cite to them settles a question definitively)? Are you aware of any of their posts that contain any mistakes or distortions? Could you list one or two things they have said that you think are unreliable?
(Exercises like this are important for credibility, because it separates the cheerleaders who always come to the same conclusion from the people who genuinely care about what is correct.)
How about the Ritson post? You might want to look at comments #11 and #12 at http://www.realclimate.org/index.php/archives/2006/05/how-red-are-my-proxies/ where they say Ritson does not do any differencing. Compare this to the Ritson paper’s first paragraph which explicitly says he is employing a differencing technique. (See http://www.realclimate.org/index.php/archives/2006/05/how-red-are-my-proxies/ for the Ritson paper itself.)
Next, a tougher one. I share Mark’s surprise at your denial that natural climate cycles are a factor in hurricane activity (note, I am not asking you to admit that they are the only factor or the major factor, just that a reasonable person might think they are a factor). In fact, I thought this was pretty well accepted.
For instance, Patrick Michaels writes that:
See http://www.worldclimatereport.com/index.php/2006/05/26/hurricaneglobal-warming-linkage-takes-another-hit/
BTW, I remember reading comments 10 years ago (when the hurricane cycle was at a minimum) that when the cycle turned up, dishonest pro-AGW people would sieze on the increase as evidence of AGW. So, I always thought that the cyclicality of hurricane cycles was a pretty well-known proposition for quite a while.
Again, I am not asking you to agree with Michaels, I am just asking if you can admit that there is some genuine science that makes it possible what he is saying might have some truth to it.
Can you do this?
#59:
David said:
My sentiments exactly. It is a bit disheartening that the least informative posts often draw the most attention. This is disheartening because there is an infinite amount of ignorance out there and so many blogs tend to degenerate into unreadability. My solution is to just ignore the cheerleading and concentrate on the most informed posts.
When you think about it, it is actually quite an extraordinary achievement that Steve M. so often has such high-quality discussions on this blog. He deserves a lot of credit.
RealClimate has some high-quality content too, but their ruthless censorship of serious criticism renders their site completely unreliable and partisan. For example, see my post above to Steve B. about the Ritson post at RealClimate (Steve M. did an extended evisceration of the post here at ClimateAudit — none of which is even hinted at on RealClimate.)
As to your four questions, I think the controversy is almost exclusively about the follow on question rather than the CO2 increase itself: what will the impact be of an anthropocentric CO2 increase. “Skeptics” believe the warming from a doubling of CO2 will be about 0.8 degrees C and/or only mildly harmful or possibly beneficial. The AGW community believes the warming will be 1.5 to 4 degrees C and catastrophic.
I have always been puzzled as to why the AGW folks considered a 0.8 degree C porjection so heretical. If the debate were more civilized, it would seem reasonable to just adjust the “concensus” range downwards a little to include the 0.8 estimate. Then, maybe we could get on to the question of what the impact will be.
Oh, and by the way there is some consensus in this debat. There is essentially 100 percent agreement that Kyoto will have virtually no effect on anything — I haven’t heard ANYONE seriously dispute this.
#61 – TCO, I don’t know which post you mean. However, statistics aren’t going to tell anyone squat about physical causality.
#59 – David, your questions 1-4 have already been discussed extensively in scientific terms on Steve M.’s site, and so I find it fatuous that someone can arrive here latterly and complain about “cheerleaders from the anti-AGW crowd.” Most people here are discussing things in an already-established context. They needn’t reiterate points already made to get you up to speed. A little benefit-of-the-doubt granted by your part would be both appreciated and warranted.
Regarding your question 1, it’s not clear that the absolute historical (as opposed to qualitative) levels of CO2 can be established by ice-core data, because of uncertainties both in recovery efficiency and in the retention of glacial CO2 over multi-millennial times. In your #2, the resolution of the ice-core CO2 record doesn’t allow reconstruction of decadally-resolved rates. It may be that all or most of the CO2 increase is due to humans, and it may be that 2100 will see 550 ppmV of CO2. However, depending on what you mean by “serious,” palliative measures taken by humans can be either rational or self-destructive. If the effects of doubled CO2 are only a 1-2 degree C rise in average atmospheric T, is that “serious” enough for you to prescribe spending trillions and halving energy production?
And just to ask: What’s your take on a switch to non-CO2-producing nuclear power?
Re #68 and #70.
***As I understand it the water vapor argument is not valid. The consensus seems to be that water vapor is a feedback not a forcing. Note Steve McIntyre’s comment in the “A few inconvenient truths” post:
Similarly, the fact that water vapour constitutes 95% of greenhouse gases by volume is conveniently ignored by Gore.
I don’t get this point at all. So what? I think that there are important and interesting issues about negative feedbacks associated with water vapor, as well as the more publicized positive feedbacks. I don’t see the purpose of exchanging soundbites of this type.***
Yes, it is unfortunate that you and some others do not like the water vapour argument. That is the problem with cherry picking. Some select only those parameters which help make their point. You will not get to the scientific bottom unless you look at all the possibilities. And you restate that there is a correlation between temperature and CO2. But you miss the important point – the causes. Can you quote a reliable study which gives cause, NOT statistical correlation.
You say “I do not get this point at all”. Well then it is time for some serious scientific reading.
What are the time span / measurement limits to past CO2 in ice core samples? In other words, do ice cores reveal year by year differences, decade to decade, century to century, etc…
#76 – the highest resolution CO2 study of which I’m aware is N. Caillon, ea (2003) “Timing of Atmospheric CO2 and Antarctic Temperature Changes Across Termination III” Science 299, 1728-1731. The abstract and a link to the full paper are here. The CO2 resolution given in that paper is +/- 200 years, which is far too coarse to test whether recent rates are paleo-unprecedented.
#68:
I’ve never understood that argument. Certainly there are natural and anthropogenic sources of water vapor. Ex.:
– Automobile catalytic converters
– Industry
– Airline exhaust (contrails)
– Volcanos
– Photochemical oxidation of methane in the atmosphere
Water vapor from these sources are not a “feedback” as far as I am aware.
re:#78
Those aren’t feedback but they’re also trivial compared to the amount of H2O evaporated from oceans. OTOH, CO2 is much more a mixed bag as the vast majority of CO2 that enters the atmosphere is from plants and the ocean. We’re told that delta CO2 must be considered a forcing however, since the amount is generally proportional to the anthropic contribution. But this means we need to divide up CO2 effects and that, for instance, if CO2 fertilization is considered, we can’t offset the biomass so produced against the human CO2 production. This doesn’t really make much sense, IMO, but apparently a lot of things can’t be allowed to make sense if you’re adamant about humans being villains.
Re #71. Charles, if doubling CO2 does not mean a doubling of its greenhouse contribution, why is there such a strong correlation between temperature and CO2?
Re #73. Terry, thanks for the support. I seems to me that a 0.8C rise in temperature is within the bounds of possibility, but then so is a 4C rise. However, arguments that a rapid temperature rise of 4C within a 100 years could actually be “good” (#67) strike me as silly. To adjust to such a dramatic change would be enormously costly for humans, and there would likely be catastrophic loss of biodiversity. Re: Kyoto: I don’t think anyone believes Kyoto will solve the AGW problem (if you accept there is one) but the measures required to solve the problem would be extremely difficult politically and economically, so its hardly surprising that Kyoto is a small first step.
Re #74. Pat, I apologise if I am going over ground that has already been covered, I don’t want to waste anyone’s time. I understand that there are uncertainties with all studies, but I was unaware of any controversy over ice core studies. Can you point me to these? Re: the seriousness of the situation: I think energy conservation and improved efficiencies are a worthwhile goal regardless of the outcome of the AGW debate, and yes, I think we should look seriously at nuclear power, or at least try to have a civilised debate about it.
Re #75. Gerald, I did not say “I do not get this point at all” I was quoting Steve McIntyre from his “A few inconvenient truths” post. It seems that Mr McIntyre does not accept the water vapor argument either (at least that’s how I read it). Re: correlation between CO2 and temperature: As I said in my post (#68) there is doubt about causation and I accept that.
David Michie : Have you read Idso’s paper on CO2/temperature sensitivity? It strikes me as the most clear and concise paper I’ve read on the subject and casts serious doubt on the higher sensitivity figures. Where do they come from anyway? Please don’t say models.
Also, aren’t we getting a little bit off topic here?
Anyone see Hawkings comments today that he is worried that the Earth could turn into another Venus?
My question is that hasn’t the earth had a co2 level that is substantially higher than it is today, as in an order of magnitude? We have never had a Venus-like climate, even with that much co2, so how on earth could a doubling of co2 do that now?
A related question….from my limited knowledge of climate history, isn’t the correlation between co2 and temperature only a short-term thing? Does it go away when looking from geological time frame?
Re #81. Wikipedia is not kind to the Isdo’s and the “Center for the Study of Carbon Dioxide and Global Change”. However I have an open mind and will I will read it.
Re #83. Yes there is evidence of decoupling of CO2 and temperature over longer timeframes, but then I believe the sun was considerably dimmer at the time. The correlation between CO2 and temperature is only “short term” if you consider 400,000 years to be short term.
Re #84. I have no comment.
#85: Surely you must know that the “correlation” even in the more recent 400 000 year record is that temperature increase precedes CO2 increase? You must also know that this record is so full of non-correlations and negative correlations between the two (T and CO2) that no meaningful cause-and-effect relationship can be established?
BTW, I suggest you read some of the Idso’s writings. I don’t agree with their apporach all the time, but I do find their analysis to be quite interesting.
The whole “center for CO2 science” of the Idsos sounds a bit ridiculous.
Pat: yes statistics can’t tell you physicality, but that’s not what you said earlier (“The only way to distinguish normal variation from human caused climate variation is to have a physical theory”). Please stop and think it through for a second. Statistics CAN show remarkability even if a microscopic understanding is lacking. For instance, certain kinds of test score patterns can be statistically shown to indicate cheating. Even though no observation of cheating has been made.
Re #59
These are my own opinions – I do not speak for any group.
Questions 1 and 2 regarding highest CO2 for 400,000 years.
Answer: No I do not agree. The CO2 levels in the Vostok ice cores are effectively thousand year averages. It is misleading to compare averages with spot readings. The average speed of a vehicle on a trip is not comparable with the instantaneous speed of a vehicle at one instant in time which is noisier and can take a much wider range of values. There appears to be nothing unusual about the CO2 concentration in the atmosphere averaged over the last thousand years. The slight rise over the last 150 years would be smoothed out by the averaging process. Evidence from the stomatic index of fossil leaves, which is an average over weeks or months shows equally large excursions at the time of the Lesser Dryas about 10,000 years ago.
Answers to Questions 3 and 4 about CO2 reaching 550 ppm and human activity and isotopes:
3. Probably not but it depends whether the sea gets that much warmer due to increases in solar irradiance which seems unlikely. See below:
4. The isotope ratios do indeed indicate that much of atmospheric CO2 results from human activity. If the oceans weren’t warming up this extra CO2 would have been absorbed by now to maintain the balance between oceanic and atmospheric CO2. This balance is determined by the temperature of the oceans. The situation is complicated by the different water masses in the ocean each of which has different CO2 residence times, diffusion rates and so on.
I believe that observed CO2 increases are the symptom rather than the cause of global warming. Certainly increasing CO2 concentrations help to warm the earth but the effect is small when compared with other heat sources.
#88 John, could you please give a reference on the stomatal index in the Lesser Dryas? Thanks
eduardo
For those interested, there is a live audio webcast from 11 a.m. to noon EDT, see http://nationalacademies.org/
Will there be a written report? What is the url for where it will be posted?
Bloom: I got the impression, you’ve gotten some rumors about the content. Dish, baby, dish. What’s it say?
re #80 David you say
“Charles, if doubling CO2 does not mean a doubling of its greenhouse contribution, why is there such a strong correlation between temperature and CO2?”
Actually there isn’t a strong correlation between temp and CO2. From ~1940 to ~1970 temp went down while CO2 continued to climb. Obviously something else was more important than CO2 during that time period.
Any CO2 temp contribution is ~ ln (CO2). This is physics, pure science, a fact. Fits the theory and is supported by experiments.
Again, continued CO2 increases of the size we have seen the last century and moderate warming (related or not) is good for the planet. Since the warming is concentrated in the higher latitudes, in the winter and at night we can expect to see slightly longer growing seasons thus more food production.
The only potential negative with any credibility is slightly higher sea levels – about 8in over the next 100yrs. If that worries you then go ahead and be worried. It doesn’t worry me.
David,
Don’t put too much weight into correlations. Think about the underlying data: how much do we really know about temperature over the last 400,000 years? After looking at the state-of-art in paleo temperature reconstructions using various proxies I’d have to say very little before 1870, and I even have doubts about the accuracy and reported resolution of reported “global temperature” before 1980. And even if you believe the temperature reconstructions they only go back 1000 years or so; everything before then is pretty much a guess. I won’t even talk about the CO2 reconstructions using ice cores, as that has already been covered recently on this thread.
And then, even if you believe the underlying data, so what? There’s a strong(er) correlation between declining stork populations and the birth-rate in Europe, but nobody is suggesting that this proves storks deliver babies. In order to show causation you need a falsifiable physical theory that explains global temperature on climatic scales, and we just don’t have one. The failure of the models shows that there still are a lot of things we don’t know.
When there’s a lack of reliable, meaningful evidence people either pick a side (the claims are true or untrue), or like me, just throw up their hands and say “I don’t know, and the data does not yet support a conclusion”. That, IMHO, is the more honest way to approach it. Could a disaster happen while we wait and collect more data? Possibly, but running off and doing “something” without quite knowing what we are really doing could be just as disasterous. So let’s be deliberate and take the time necessary to study this sufficently before acting. Despite what some say about a “tipping point”, etc., all the evidence suggests that large climate changes occur over long time periods, so we have the time.
Re#94 Paul,
BINGO! Your post summarizes exactly how I feel. But you’ll still be tossed into the sceptic/skeptic/septic crowd.
looks like there is a book that you can buy.
http://fermat.nap.edu/catalog/11676.html
“When there’s a lack of reliable, meaningful evidence people either pick a side (the claims are true or untrue), or like me, just throw up their hands and say “I don’t know, and the data does not yet support a conclusion”.”
I’d say your actually stating what is the other side. i.e. it’s not “the claims are true or untrue” it is “the claims are true or the data does not yet support a conclusion.” I don’t think anyone is actually saying that the temprature has cooled in the past 30 years. Its the “we’re all going to die” that we are skeptical of, and this includes the magnitude of future warming.
I can’t find a link to the webcast on that page. Can someone direct me to it?
Thanks.
Re #98
According to their news office page , “Every live webcast is launched from our home page.”
So presumably something will pop up at the appropriate time.
Washington is 5 hours behind London, isn’t it ?
should be starting any minute now
Re #99
It did, thanks.
The Mark that replied in #83 is not the same Mark as the one that replied to Dano and Steve Bloom earlier, btw. I’ll post as Mark T. henceforth to remove doubt.
And, w.r.t. Mark’s post: Yes, CO2 has been an order of magnitude above now and even during ice ages, all within “recent” history. Geologically, there is a rather sound argument that it typically lags temperature rises by 800 years.
Mark
Not impressed …
Frigging real player. Why don’t they have a wmp play. I even tried downloading and installing it, but no go.
TCO, use Media Player Classic. It deals with Real Player files just fine.
Congratulations, Steve. You’ve been vindicated, I’d say.
re: 49. Dano: for HUNDREDS of peer-reviewed articles that refute everything you say, see here.
87
WHY?
I’m sitting at a library computer terminal and I don’t know if the embargo is lifted or not (I couldn’t watch the briefing), but I like this, from page 111:
“Some of these [M&M] criticisms are more relevant than others, but taken together, they are an important aspect of a more general finding of this committee, which is that uncertainties of the published reconstructions have been underestimated.” (my bold)
And on page 21 they say that Mann’s conclusion about late-20th century anomalous warmth is ‘plausible’. This is damning with feint praise, especially when in the next line they say: “Even less confidence can be placed in the original conclusions by Mann et al. (1999) that ‘the 1990s are likely the warmest decade, and 1998 the warmest year, in at least a millennium’.”
Chapter 11, on statistics, is quite a good read.
Jae:
1. They give themselves airs (“institute”, “president” etc.)
2. Very small activity (unlike implied by the lofty titles).
3. All the workers are members of one family.
4. Appears to be self-funded, presumably on a shoestring.
5. No significant recent peer-reviewed publications.
6. Not even clear that they are really working full time on their Institute duties.
Basically 3 guys in a house in Idaho with a website. Looks silly.
RE 10 If the hockey stick is broken
“Can you please be more specific about how the methods used in MBH98 have affected later wstudies?”
Last year I did an analysis of Crowley’s “Causes of Climate Change Over the Past 1000 Years.”
on the basis that ths sun was driving the temperature,that CO2 had little or no effect,that his volcanic effects were real and aerosols etc. had hardly any effect.Using globally measured temperatures up to 1990 as a basis
The resultant temperature graph had a MWP about 2 degrees higher and a LIA about 1 degree lower than present. Although this is not conclusive it does indicate that CO2 has a much lower efect on temperature than the global warmers say.
re: #110
And just what does that make Steve M then? One guy in a house in Canada with a blogsite? And BTW, last I knew the Idso’s or at least the father was living here in Tempe, AZ. (The name is Norwegian, BTW, not Japanese or something as I’d guessed at one time.)
And for that matter what does that make you, a guy with a brokebacked browser and a keyboard?
110. They have reviewed and summarized HUNDREDS of peer-reviewed studies, as well as published many of their own, TCO. Look at the index here.
#87 – TCO, I don’t think I’ve ever ascribed explanation in terms of physical causality to anything except physical theory. One of the most basic realities of statistical conclusion-making is that statistical correlations do not predict the outcome of any individual case. It’s quite possible for some physical system to produce a result that falls into a statistical manifold, but which has a physical cause different from those which constituted the statistical basis set. Likewise, someone’s test score may show a pattern associated with cheating, however that association in and of itself is no indication that cheating occurred in any individual case.
#93 – You caught my view-point well, too, Paul. And this vastly under-appreciated point: “running off and doing “something” without quite knowing what we are really doing could be just as disasterous” completely vitiates the so-called “precautionary principle.”
Re #114, #87
TCO, in short, “Correlation does not imply causality”.
And speaking as someone who has had to resit a test because they didn’t believe the first score, Pat is entirely correct about that point too.
The “precautionary principle” is a logical fallacy, because it justifies action for any SUPPOSED problem. The damn governmental toxicologists use it all the time to justify rediculously low allowable exposures to chemicals. And they even “cascade” the principle (e.g, assume a linear dose-response relationship, “just to be cautious”, divide the obviously safe dose by 100, “just to be cautious,” assume a person is exposed continuously for 70 years, “just to be cautious,” etc., etc. etc.
Fred and Pat, I get that. I always got that. What I disagreed with was Pat’s remark that remarkability can only be inferred when the process is known physically. This is not true.
Here is Pat’s statement:
If I see someone roll 7 snakeeyes in a row, I can make a very very likely and useful inference that the dice are loaded, without any knowledge of the dice construction, without destructive testing to look at their innards, without special weighting experiments, etc.
It’s a subtle point, but one that I want to drive home to Pat.
jae:
1. Steve impresses me more in his quality of thought.
2. And he doesn’t put on airs by calling himself an institute head.
TCO: SO? I like Steve’s style and accomplishments, too; but not to the exclusion of all other sources of info.
I agree with multiple sources of info, also. Above comments (from before) all still stand.
Re: #117
The precautionary principle presents a logical contradiction in that any precautionary measure in itself entails uncertain risk so must be prohibited.