cc: Caspar Ammann , rbradley@geo.umass.edu, tcrowley@duke.edu, mhughes@ltrr.arizona.edu, omichael@princeton.edu, t.osborn@uea.ac.uk, jto@u.arizona.edu, Scott Rutherford , Tom Wigley , p.jones@uea.ac.uk, mann@virginia.edu date: Mon, 13 Oct 2003 22:36:48 -0400 from: "Michael E. Mann" subject: Re: draft to: "Malcolm Hughes" , Keith Briffa , Kevin Trenberth Dear All, I plan to send out another revised version tomorrow. A few brief comments: 1) Re boreholes, my apologies. The statement on why the borehole estimates are confined to the past 500 years was not made in Huang et al (2000), but instead the earlier paper by Pollack et al (1998): "The combination of the predominant depth range of observations and the characteristic magnitude of noise has led us to choose five centuries as the practical interval over which to develop climate reconstructions". Will substitute in the correct reference, but keep the wording the same... 2) Regarding the final paragraph, I've shortened the discussion (e.g. removed the bit about the publisher) so as to downplay this, but haven't eliminated it all together. We can have an up or down vote on whether or not to keep it once we finalize the draft... 3) Malcolm's revision of the first paragraph would be great if we had 900 words, but we don't. The limit is 750, and they've indicated that they will be strict about this. So I'll try to reduce Malcolm's additions to one or two summarizing sentences. More tomorrow. Thanks, mike At 06:58 PM 10/13/2003 -0700, Malcolm Hughes wrote: Dear Mike and all, Please find attached some small edits that I propose (MS-Word *.doc file with track changes turned on). The first change you will find is designed to incorporate and give strong emphasis to Keith's very important point about keeping the focus on the inadequacies of the SB approach, and their failure to deal with our specific criticisms. This is far and away the most important point to make. The second main change I suggest concerns the words about boreholes. A careful reading for the papers they referred to simply does not justify the wording in Mike's most recent draft, since Huang, Pollack etc. never say exactly why they stop at 500 years rather than 400 or 1000. It is, however, the case that the Huang et al 1997 paper to which they refer has a multi-century hump about a thousand years ago, but it can't be compared with a period of 25 or 30 years. I don't see much point in the Folland et al citation, because it is not a primary source. Finally, I am in two minds about the last paragraph of Mike's draft. On the one hand, I understand the need to get the word out about the disquiet many feel about the circumstances surrounding publication of the SB et al papers, but I also suspect that our scientific arguments alone are more than enough to undermine their position. We may, in fact, be seen by many colleagues as making an ad hominem attack, and so arouse the suspicion that our scientific case is not strong enough to stand on its own. I suggest we think carefully before proceeding with the last paragraph as it stands. Cheers, Malcolm > > Dear All, > > Thanks for all your comments, which are very helpful. I've done my > best to address these within the pretty tight constraints (750 words) > allotted. We come in now at 746 words, just inside the strict 750 word > limit that has been imposed on us. > > We have 6 references now--I've asked folks at AGU if that's ok. > > If people have any final comments on the draft, please let me know > ASAP. For those who haven't yet responded yet (Malcolm, Ray, Caspar, > Scott, Peck), if you're happy w/ it as it currently stands, a simple > "looks good as is now, sign my name to it too" would be great. I don't > want to sign anyones name to this w/ out some indication of approval. > I realize some of you are still travelling and have been unable to > respond. I've asked AGU if we can have at least one more week before > submitting... > > Thanks again for your continued help, > > mike > > At 04:36 PM 10/13/2003 +0100, Keith Briffa wrote: > > Mike and all > Hi , just back from a trip and only now catching up with important > emails. Given the restricted time and space available to furnish a > response to SB comments , I offer the following mix of comment and > specific wording changes: > > I agree that the S+B response is designed to deflect criticism by > confusing the issues rather than answering our points. In fact > they fail to address any of the 3 specific issues we raised Namely > , 1. the need for critical evaluation of proxy inputs , 2. the > need for a consistent assimilation of widespread (dated and well > resolved ) records, 3. the essential requirement for > objective/quantitative calibration (scaling) of the input records > to allow for assessment of the uncertainties when making > comparisons of different reconstructions and when comparing early > with recent temperatures. Their own , ill-conceived and largely > subjective approach did not take account of the uncertainties and > problems in the use of palaeodata that they chose to highlight in > their opening remarks. I would be in favour of stating something > to this effect at the outset of our response. > > Also , as regards the tree-ring bit , I fully concur with the > sense of your text as regards Section 1, but suggest the following > wording (to replace ",rarely for annual ring widths, and almost > entirely at higher latitudes.") "but in certain high-latitude > regions only. Where this is the case , these relatively recent (ie > post 1950) data are not used in calibrating temperature > reconstructions. In many other (even high-latitude) areas density > or ring-width records display no bias." > > In the spirit of healthy debate - I agree with Tim's remarks , > warning against presenting a too sanguine impression that the > borehole debate is closed ( though I do think it is closing!). I > also believe , as you already know, that the use of a recent > padding algorithm to extend smoothed data to the present time, is > inappropriate if it assumes the continuation of a recent trend. > This is likely to confuse , rather than inform, the wider public > about the current climate state . > > Finally , I repeat my earlier remarks (made before EOS piece > published) that we are missing an opportunity to say that a warm > Medieval period per se is not a refutation of anthropogenic > warming , {as its absence is no proof}, if we do not understand > the role of specific forcings (natural and anthropogenic) that > influenced medieval and current climates. > > Cheers > Keith > > At 12:48 PM 10/9/03 -0600, Kevin Trenberth wrote: > Hi all > Here are my suggested changes: toned down in several > places.Tracking turned on Kevin > > Michael E. Mann wrote: > Dear co-authors, > > Attached is a draft response, incorporating suggestions Kevin, Tom > W, and Michael. I've aimed to be as brief as possible, but hard to > go much lower than 750 words and still address all the key issues. > 750 words, by the way, is our allotted limit. > > Looking forward to any comments. Feel free to send an edited > version if you prefer, and I'll try to assimilate all of the > suggested edits and suggestions into a single revised draft. If > you can get comments to me within the next couple days, that would > be very helpful as we're working on a late October deadline for > the final version. > > Thanks for your continued help, > > mike > > _________________________________________________________ > _____ > Professor Michael E. Mann > Department of Environmental Sciences, Clark Hall > University of Virginia > Charlottesville, VA 22903 > _________________________________________________________ > ______________ > e-mail: <[1]mailto:mann@virginia.edu >mann@virginia.edu Phone: > (434) 924-7770 FAX: (434) 982-2137 > [2]http://www.evsc.virginia.edu/faculty/people/mann.shtml > > > -- > **************** > Kevin E. Trenberthe-mail: > <[3]mailto:trenbert@ucar.edu>trenbert@ucar.edu > Climate Analysis Section, > NCAR<[4]http://www.cgd.ucar.edu/cas/>[5]www.cgd.ucar.edu/cas/ > P. O. Box 3000,(303) 497 1318 > Boulder, CO 80307(303) 497 1333 (fax) > > Street address: 1850 Table Mesa Drive, Boulder, CO 80303 > > -- > Professor Keith Briffa, > Climatic Research Unit > University of East Anglia > Norwich, NR4 7TJ, U.K. > > Phone: +44-1603-593909 > Fax: +44-1603-507784 > > [6]http://www.cru.uea.ac.uk/cru/people/briffa/ > > ____________________________________________________________ > __ > Professor Michael E. Mann > Department of Environmental Sciences, Clark Hall > University of Virginia > Charlottesville, VA 22903 > ______________________________________________________________________ > _ e-mail: mann@virginia.edu Phone: (434) 924-7770FAX: (434) 982-2137 > [7]http://www.evsc.virginia.edu/faculty/people/mann.shtml - - Malcolm K. Hughes Professor of Dendrochronology Laboratory of Tree-Ring Research W. Stadium 105 University of Arizona Tucson, AZ 85721 USA e-mail: mhughes@ltrr.arizona.edu telephone: 520-621-6470 fax:520-621-8229 [8]www.ltrr.arizona.edu ______________________________________________________________ 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 [9]http://www.evsc.virginia.edu/faculty/people/mann.shtml