From	Michael E. Mann	Date	Tue, 14 Oct 2003 12:35:34 -0400
To	Caspar Ammann
CC	Tim Osborn, Malcolm K. Hughes, Keith Briffa, ray bradley, Tom Crowley, Michael Oppenheimer, Jonathan T. Overpeck, Scott Rutherford, Tom Wigley, Phil Jones, Kevin Trenberth
Subject	Re: Fwd: Re: draft
thanks Caspar, I agree--its important to emphasize this point, and I'm glad you recognized that we were underplaying it... mike At 10:25 AM 10/14/2003 -0600, Caspar Ammann wrote: Mike, looks good to me. It is one of these points where they can persuade journalists that they are 'correct' and it actually got into newspapers and finally to the senate floor this way. The more we are able to explain why the first half of the 20th century warmed up naturally, the more confidence we get on the detection of the anthropogenic signal afterwards. Caspar Michael E. Mann wrote: Dear All, In response to Caspar's suggestion, which I agree with, I propose rephrasing item "2" as follows: 2) The statement by S03 that the Mann and Jones [2003] reconstruction "clearly shows temperatures in the MWP that are as high as those in the 20th century" is misleading if not false. M03 emphasize that it is the late, and not the early or mid 20th century warmth, that is outside the range of past variability. Mann and Jones emphasize conclusions for the Northern Hemisphere, noting that those for the Southern Hemisphere (and globe) are indeterminate due to a paucity of southern hemisphere data. Consistent with M03, they conclude that, late 20th century Northern Hemisphere mean temperatures are anomalous in a long-term (nearly two millennium) context. Any comments? Thanks, mike Delivered-To: [1]mem6u@virginia.edu Date: Tue, 14 Oct 2003 09:18:37 -0600 From: Caspar Ammann [2] Organization: NCAR User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en To: "Michael E. Mann" [3] Subject: Re: draft Hi Mike, it now looks good to me indeed including the new last paragraph following Tom's wording. The only point I would highlight a little more is in point 2): Maybe it could be stated that the early part of the 20th century is within the natural range whereas the late 20th century, the main point of the AGU position statement and also in M03, is clearly outside. Please also add a second 'n' in my name... Cheers, and thanks for your momentum on this, Caspar Michael E. Mann wrote: Dear All, I agree with each of Tom W's suggestions. Adopting them, by the way, brings us down to 738 words. So pending any revised language from Keith/Malcolm in response to Michael O's comment on paragraph 2, I'm putting out a last call for comments, sign-ons, etc... Thanks, mike At 08:00 AM 10/14/2003 -0600, Tom Wigley wrote: Some minor points .... para. 2 -- should it be 'an' ensuing rather than 'the' ensuing? para. 2 -- I still think 'each' (line 3) is unnecessary para. 4 -- no comma after '(and globe)' re boreholes, does the point about comparing late 20th century with a 'much longer period' 1000 years ago help us? Given that the 1000 years ago data is highly lowpass filtered, if one *did* have a series with a temporal resolution that allowed a legitimate comparison, then the likelihood of a warmer interval 1000 years ago must be higher. In any event, the time scale issue will not be meaningful to most readers. The key point is the data reliability/uncertainty. I would just say something like ... ".... taken into account. For times more than 500 years ago, uncertainties in the borehole reconstructions preclude any useful quantitative comparison." Finally, I would like the last para. retained, but I suggest shorter wording as ... ".... as indicating that SB03 misinterpreted and misrepresented the paleoclimatological literature. The controversy ....". My problem here is twofold. First, they really say nothing directly about 'mainstream scientific opinion' (except that they clearly disagree with it). At issue is not the mainstream opinion, but their interpretation of the literature and their illogical conclusions. Second, they may have misrepresented the results of their work, but we do not address this issue so it comes here as a non sequitur. In fact, just what such 'misrepresentation' consists of, and why it might be judged as 'misrepresentation' is a subtle issue. Hence my revision -- which retains the word 'misrepresentation', but in a different context. Tom. +++++++++++++++++++++++++++++++== Michael E. Mann wrote: Thanks Tim and Malcolm, The latest round of suggestions were extremely helpful. I've accepted them w/ a few minor tweaks (attached). We're at 765 words--I think AGU will let us get away w/ that... So, comments from others? Thanks, mike At 02:11 PM 10/14/2003 +0100, Tim Osborn wrote: SO3 argue that borehole data provide a conflicting view of past temperature histories. To the contrary, the borehole estimates for recent centuries shown in M03 may be consistent with other estimates, provided consideration is given to statistical uncertainties, spatial sampling and possible influences on the ground surface [e.g., snow cover changes--Beltrami and Kellman, 2003]. It is not meaningful to compare the late 20th century with a much longer period 1000 years ago [Bradley et al., 2003], especially given the acknowledged limitations [Pollack et al., 1998] of borehole data. ______________________________________________________________ Professor Michael E. Mann Department of Environmental Sciences, Clark Hall University of Virginia Charlottesville, VA 22903 _______________________________________________________________________ e-mail: [4]mann@virginia.edu Phone: (434) 924-7770 FAX: (434) 982-2137 [5]http://www.evsc.virginia.edu/faculty/people/mann.shtml ______________________________________________________________ Professor Michael E. Mann Department of Environmental Sciences, Clark Hall University of Virginia Charlottesville, VA 22903 _______________________________________________________________________ e-mail: [6]mann@virginia.edu Phone: (434) 924-7770 FAX: (434) 982-2137 [7]http://www.evsc.virginia.edu/faculty/people/mann.shtml -- Caspar M. Ammann National Center for Atmospheric Research Climate and Global Dynamics Division - Paleoclimatology Advanced Study Program 1850 Table Mesa Drive Boulder, CO 80307-3000 email: [8]ammann@ucar.edu tel: 303-497-1705 fax: 303-497-1348 ______________________________________________________________ Professor Michael E. Mann Department of Environmental Sciences, Clark Hall University of Virginia Charlottesville, VA 22903 _______________________________________________________________________ e-mail: [9]mann@virginia.edu Phone: (434) 924-7770 FAX: (434) 982-2137 [10]http://www.evsc.virginia.edu/faculty/people/mann.shtml -- Caspar M. Ammann National Center for Atmospheric Research Climate and Global Dynamics Division - Paleoclimatology Advanced Study Program 1850 Table Mesa Drive Boulder, CO 80307-3000 email: [11]ammann@ucar.edu tel: 303-497-1705 fax: 303-497-1348 ______________________________________________________________ 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 [12]http://www.evsc.virginia.edu/faculty/people/mann.shtml References 1. mailto:mem6u@virginia.edu 2. mailto:ammann@ucar.edu 3. mailto:mann@virginia.edu 4. mailto:mann@virginia.edu 5. http://www.evsc.virginia.edu/faculty/people/mann.shtml 6. mailto:mann@virginia.edu 7. http://www.evsc.virginia.edu/faculty/people/mann.shtml 8. mailto:ammann@ucar.edu 9. mailto:mann@virginia.edu 10. http://www.evsc.virginia.edu/faculty/people/mann.shtml 11. mailto:ammann@ucar.edu 12. http://www.evsc.virginia.edu/faculty/people/mann.shtml