From: Phil Jones To: "Michael E. Mann" ,rbradley@geo.umass.edu, k.briffa@uea.ac.uk,mhughes@lttr.arizona.edu,t.osborn@uea.ac.uk, srutherford@virginia.edu,mann@virginia.edu Subject: Re: AGU abstract Date: Tue, 13 Aug 2002 10:16:42 +0100 Mike, Checked with Keith and Tim. The abstract is like one we would write - leaves all options open as to what will be presented. At least AGU and EGS don't charge to get abstracts printed. AMS have so many missing now with their charges that the book of abstracts is ridiculous. Fine for all three of us to be there and we look forward to seeing some results in the autumn. This will be when the real action begins. The CCDD meeting in early Nov. might be at a good time to discuss some results. Add an 'of' between choice and actual on the third line. Cheers Phil At 19:56 12/08/02 -0400, Michael E. Mann wrote: Dear all, The following is an abstract for a talk I've been invited to give at the winter AGU meeting in a session on "Climate of the Past 2000 Years". I would like to summarize the collaborative work that was begun by Scott, Tim and myself a couple summers ago during Tim's visit here. Scott is working on finalizing the results of our analyses now, and a draft should be available for review shortly that compares reconstructions based on our covariance-based reconstruction method, using (i) multiproxy, (ii) MXD, and (ii) combined multiproxy+MXD datasets for different (cold, warm, annual) target seasonal windows. I'd like to invite everyone listed below to be authors on both this abstract, and the paper that we're in the process of drafting, describing the results. I've kept the abstract intentionally vague, so that we can work out an interpretation of the results that we're all comfortable with in the months ahead, prior to the talk, and submission of the paper. I look forward to confirmation of your interest in being a co-author, and any feedback you have. I'd like to submit this by the end of the week, which will be my last opportunity to do so prior to the AGU abstract deadline, owing to my travel schedule. thanks in advance for getting back to me ASAP. best regards, Mike _____________________________________________________________________________ Progress in Proxy-Based Reconstruction of Surface Temperature Variations in Past Centuries Michael E. Mann Raymond Bradley Keith Briffa Malcolm Hughes Philip Jones Timothy Osborn Scott Rutherford Results are presented from a set experiments designed to control for the various factors that may influence reconstructions of large-scale temperature patterns in past centuries, including (a) the choice actual proxy data used, (b) the reconstruction methodology, (c) the spatial domain of the reconstruction and (d) the seasonal window targeted. These experiments compare results based both on the global multiproxy data set used by Mann and coworkers and the extratropical Northern Hemisphere maximum latewood tree-ring density set used by Briffa and coworkers. Estimates of hemispheric mean temperature trends are formed both through averaging of large-scale patterns reconstructed from full proxy data network, and through simple compositing of regional temperature reconstructions. Northern hemisphere mean estimates are compared for the full Northern hemisphere (tropics and extratropics, land and ocean), and extratropical continents only, and using various (cold-season half year, warm-season half year, and annual mean) seasonal targets for the reconstructions. Implications of these experiments for the robustness of proxy-based reconstructions of past large-scale temperature trends are discussed. _______________________________________________________________________ Professor Michael E. Mann Department of Environmental Sciences, Clark Hall University of Virginia Charlottesville, VA 22903 _______________________________________________________________________ e-mail: mann@virginia.edu Phone: (434) 924-7770 FAX: (434) 982-2137 [1]http://www.evsc.virginia.edu/faculty/people/mann.shtml 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 ---------------------------------------------------------------------------- References 1. http://www.evsc.virginia.edu/faculty/people/mann.shtml