From: Keith Briffa To: mann@psu.edu Subject: Re: expert review comments on AR4 Date: Thu May 25 17:34:59 2006 Hi Mike thanks for these comments and especially thanks for your remarks on the effort of trying to produce a balanced picture of the current state of things in the IPCC Chapter 6. In fact , I know that it is already out of date and I am going to get particularly lambasted for not discussing problems with recent tree responses to warming and potential problems wit CO2 fertilization - I may have to add even more text yet .You are absolutely correct that we had unreasonable trouble from Susan , who was not as "hands off" as she might have been. I will certainly study your comments carefully - as I always do . I would rather reserve comment on the Crowley reconstruction til I speak personally to you. I really hope that we can get an atmosphere of constructive discussion that , I believe, must include some discussion of the sceptics . Look forward to those drinks and some time away from the mad house of teaching/exam marking etc. See you soon best wishes Keith At 18:08 24/05/2006, you wrote: Hi Keith, I wanted you to have an advance copy of the comments I'll be submitting on the final draft of the AR4. I commend you for the excellent work you've done and the tough battle I know you have had to fight. I don't envy it, and you know the tough battles I've been through. Confidentially, I do have a number of specific concerns mostly in the area of discussions of where things actually now stand in terms of some of the earlier criticisms. I believe that the discussion is still out of date, given what has been shown in recent publications, including Wahl and Ammann (Science). Also, and I don't think this is the only place you're going to hear this from, there are deep problems w/ Hegerl et al '06, particularly the claims of what TLS can do, which are egregiously incorrect. There is a comment in review in Nature (not me, but I can promise you, by someone who understands the statistical issues involved better than anyone else in our community) that is very critical. I think its unwise for the TAR to uncritically accept the claims made, particularly given that the actual J. Climate paper was in limbo at least at the time the most recent draft was finalized. I believe that disqualifies it for consideration for AR4, no? Also, I think it is an absolute travesty that figure 6.10 isn't being shown in the SPM. I think that is unforgiveable, and there should be an effort to over-ride that decision (I would suspect that is Susan Solomon's doing?), I hope we can discuss these things (and much else) over a few beers in Switzerland. Looking forward to seeing you soon, mike -- Michael E. Mann Associate Professor Director, Earth System Science Center (ESSC) Department of Meteorology Phone: (814) 863-4075 503 Walker Building FAX: (814) 865-3663 The Pennsylvania State University email: [1]mann@psu.edu University Park, PA 16802-5013 [2]http://www.met.psu.edu/dept/faculty/mann.htm -- Professor Keith Briffa, Climatic Research Unit University of East Anglia Norwich, NR4 7TJ, U.K. Phone: +44-1603-593909 Fax: +44-1603-507784 [3]http://www.cru.uea.ac.uk/cru/people/briffa/ References 1. mailto:mann@psu.edu 2. http://www.met.psu.edu/dept/faculty/mann.htm 3. http://www.cru.uea.ac.uk/cru/people/briffa/