date: Fri Mar 14 16:15:09 2008 from: Phil Jones subject: Re: Fwd: Re: Pielke et al to: Thomas C Peterson , David Parker David, If I didn't know Tom better, I might have surmised that he had a beer or two over lunch ! There is one issue about a full paper and a comment. For the comment Roger gets the last say! I agree with all Tom's points. If you want to keep the comment format, then you'll have to reduce a bit and concentrate on the more important points. I think you'll have to do much more to get a fuller paper. Of the 7 that Tom has listed, I think we could omit #2 and 7. On 2 we agree with Roger, but it wouldn't make much difference, as we assess homogeneity with tests. I don't think a series of pictures will help that much. On 7 we're agreeing anyway, so omit it. The key ones to my mind are - in importance are 5 - the plot John will do will demolish this 4 - this makes little difference at large scales provided things like TOBS have been taken out As an aside the bias adjustments in the SST data are far more important than anything up with the land. All you have to do a moderately reasonable job with land and you'll be fine. Someday, one of these, will realise this. Roger can't see this, as he's full of Tom's baloney. Why does everyone go on about the land? 3. Willett et al show specific humidity goes up in line C-C relationship. Paper has gone back today to J. Climate. 2 of the mildest reviews I've ever seen, so I think it will be accepted pretty soon. The editor is making work for themselves if this goes back for further review. 1 As there is little difference between Tx and Tn warming, if you can't use Tn then you have to use Tx. Globally the DTR trend to lower values has to be reduced to one third as the Tx/Tn concept have little meaning over the ocean. and then 6 - this is discussed elsewhere, so could be omitted. He should be referring to Simmons et al (2004) and the CCSP report. Have a good weekend. It's been sunny here today and felt warm! It could be land use change outside our building, higher vapour pressure, but I don't care - it feels warm and that is what matters! Cheers Phil At 18:12 13/03/2008, Thomas C Peterson wrote: Hi, David, My first thought is well, we'll just have to cut it way back. Then I pulled out Pielke's paper and saw that mountain of baloney and thought where do we draw the line? There is so much there that should be refuted. To be pithy, we could just hit the central points with little elaboration: 1. Definition of global temperature (a) Roger gives a definition related heat content and climate feedback. We give this definition: the average temperature of the earth. (B) Roger says we shouldn't use minimum temperatures because they can be impacted by wind. We say temperatures in the nocturnal boundary layer are temperatures that the world, including plants, animals and us, experience and are therefore can not be left out of global average surface temperature or it is no longer global average surface temperature. 2. Lack of photographic metadata. Roger says this is a major omission because, if we had them over time, they might document local changes unrelated to larger-scale climate signals. We say they would be nice but they don't exist world wide and particularly back through time, therefore we've developed statistical tests that identify undocumented changes in the local environment and adjusts the data to account for them. 3. Surface water vapor. Roger says "ignoring concurrent trends in surface air absolute humidity therefore introduces a bias in the analysis of surface air temperature trends". We say baloney. Paying attention to them would introduce a bias. Like clouds and solar energy, water vapor can impact the temperature. But the temperature is the temperature no matter what the cause so do anything other than ignoring water vapor would bias the record. 4. Uncertainties in homogeneity adjustments. Roger says there are uncertainties and potential improvements that could be made in homogeneity adjustments. We agree, which is why homogeneity research continues (reference, e.g., the Hungarian series of conferences). But we should also note that the same is true with magnetic resonance imaging in doctors' offices but we still rely on those data because the current processing is the best that is currently available and gives reliable results. 5. Degree of interdependence. Roger quotes an off the top of his head answer to the question rather than conducting any real assessment of the interdependence of climate data to point out that of course they give the same answer. We should note that (a) studies of subsets of the data have revealed essentially the same signal and (b) MSU data are 100% the same but different groups come up with different results. So processing can make big differences. Therefore, the fact that different sfc temp analyses show the same thing supports the view that the signal is robust. 6. Relationship between obs and reanalysis. Roger says obs are wrong because they don't agree with reanalysis for trends. However, a body of experts (ccsp 1.1) says it doesn't trust reanalysis trends for many valid reasons. 7. Influence of land cover change. Roger says land cover changes can impact temperature. We agree. If they are major regional changes, land cover produced changes in temperature would be part of teh signal we want to capture. If they are local, then the latest homogeneity adjustment methodology has been shown to remove them (Menne & Williams I believe). Conclusion: Roger is full of baloney. There you go, David. Add in a few references and we have a paper! Regards, Tom David Parker said the following on 3/13/2008 12:25 PM: Phil, Tom Thanks for your comments. I have incorporated many of these including quite a bit of the "Menne and Peterson" simulation of Hale et al. 2006 using SST. Should Matt Menne become an author? John Kennedy will create time series by sub-sampling alternate grid boxes of the surface temperature fields. The results will affect the wording so only when this is done will I will send you a copy. The text, which now includes summaries of Pielke et al's main points, is now nearly 4000 words plus references. This plus 2 diagrams is virtually certain not to fit in 4 JGR pages which is the limit for "Comments" (see [1]http://www.agu.org/pubs/comments_guidelines.html) So we may need to reconsider what we include, or submit it as a paper in its own right. The Hale et al simulation and the global sub-sampling exercise may go beyond AGU's stipulation: "The Comment addresses significant aspects of the original paper without becoming essentially a new paper". Anyway, I'll keep you posted on progress. Regards David On Tue, 2008-03-11 at 12:08 +0000, Phil Jones wrote: David, Don't refer to the Chinese paper that I have submitted. I'm just sending this for a few more places where the cancelling of homogeneity adjustments has been shown. The best of these is the French one. Figure 9 of the Caussinus/Mestre pdf. I asked Olivier Mestre to produce a histogram of the adjustment factors for the French Tx, Tn homogeneity. This is the png file, showing the bimodal distribution. I took this to be the counts of adjustments of certain values. What I'm suggesting you do is refer to Olivier's paper and maybe Menne and Williams, as well as Brohan et al. I got a bit carried away attaching all the things I have! Cheers Phil Date: Mon, 10 Mar 2008 12:41:47 -0400 From: Thomas C Peterson Subject: Re: Pielke et al To: David Parker Cc: "Jones, Phil" User-Agent: Thunderbird 2.0.0.12 (Windows/20080213) X-UEA-Spam-Score: 0.0 X-UEA-Spam-Level: / X-UEA-Spam-Flag: NO Dear David & Phil, I think you have a great start on the rebuttal, David. While I have many minor comments or edits in the attached version, there is one systematic change that I think we need to make: Each section should start out with a 1 or two sentence summary of Pielke et al.'s key point. Then we add our stuff (which you've written). But then we need a 1 sentence summary each time where we say, therefore Roger's point is (choose one or several): irrelevant, not supported by the evidence or refuted by the evidence. I'd prefer some stronger and less technical language, but I know you're too polite to write any such thing. Does that sound reasonable? Also, Phil, I have two questions for you in my comments. We do need to expect that Roger will want to pick any nits we have showing, so (a) we should only state the barest and clearest of cases and (b) be ready for an onslaught of babble. Regards, Tom David Parker said the following on 3/7/2008 11:34 AM: Tom Thanks for your comments on Pielke et al. JGR 2007. I have incorporated your thoughts into my draft response - please see attached. Regards David -- Thomas C. Peterson, Ph.D. NOAA's National Climatic Data Center 151 Patton Avenue Asheville, NC 28801 Voice: +1-828-271-4287 Fax: +1-828-271-4328 Prof. Phil Jones Climatic Research Unit Telephone +44 (0) 1603 592090 School of Environmental Sciences Fax +44 (0) 1603 507784 University of East Anglia Norwich Email p.jones@uea.ac.uk NR4 7TJ UK ---------------------------------------------------------------------------- -- Thomas C. Peterson, Ph.D. NOAA's National Climatic Data Center 151 Patton Avenue Asheville, NC 28801 Voice: +1-828-271-4287 Fax: +1-828-271-4328 Prof. Phil Jones Climatic Research Unit Telephone +44 (0) 1603 592090 School of Environmental Sciences Fax +44 (0) 1603 507784 University of East Anglia Norwich Email p.jones@uea.ac.uk NR4 7TJ UK ----------------------------------------------------------------------------