From: Jonathan Overpeck <jto@u.arizona.edu>
To: edwardcook <drdendro@ldeo.columbia.edu>
Subject: Re: NRC study
Date: Tue, 14 Mar 2006 00:32:37 -0700
Cc:  Keith Briffa <k.briffa@uea.ac.uk>, Eystein Jansen <eystein.jansen@geo.uib.no>

   Hi Ed - thanks for trying to fit something in quick for the NRC group. I'm not sure about
   Richard's full motives, but I think he has his heart in the right place - that the NRC
   Committee might have gotten the impression he did, and this will be reflected in their
   report, perhaps in a way that is even less satisfactory to you and Keith. And, this report
   will likely have enormous political potential. It needs to get things as right as possible
   from the start. So... time well spent on the part of you and Keith. Thanks much, peck

     Hi Peck,

     Being in Bangkok, on to PACLIM, on to CONCORD in Mendoza, back to Bangkok, and back to
     NY on May 1 makes it difficult for me to do much, but I will do what I can to salvage a
     bad situation. The longish emails I sent out to you all contain much of what I would
     write. The main point to make, one that Richard seems to be totally oblivious to, is
     that there is no evidence for loss of sensitivity prior to the 20th century in a
     large-scale NH sense like that seen in the 20th century. On the other hand, there is
     evidence that there was not a loss of sensitivity in a large-scale NH sense in my QSR
     paper (Fig. 6). I acknowledge the weakness in the data prior to about 1200, but even so
     the regional comparisons only show divergence between north and south in the 20th
     century, with none indicated during the putative MWP. So why is Richard and the NRC
     panel apparently stating without evidence that divergence probably is a problem in the
     past and, therefore, tree rings cannot be trusted to reconstruct past temperatures? It
     is honestly unscientific when the only evidence that I have seen refutes that premise,
     and it plays unfairly into McIntyre's hand. I almost admit to being very irritated that
     Richard should anoint himself as the arbitrator of this debate. He knows nothing
     substantive about tree rings. In that sense, he is just like Ray Bradley.

     Cheers,

     Ed

     On Mar 14, 2006, at 6:29 AM, Jonathan Overpeck wrote:

     Hi Ed and Keith - I hate to say it, but Richard's take on the political aspects of the
     NRC vs. IPCC reports seem worth some extra effort. Since you were both invited to speak
     with the NRC committee, I would suggest that you both (together or separately) submit
     formal comments asap. I don't know when the comment period starts or ends, but I'm
     guessing you have to work fast. I'm also thinking that you two might want to get out a
     peer-reviewed paper on the topic really soon too. I worry that the hole will continue to
     deepen for dendroclimate if you two don't act to clarify what we know/don't know, and
     when it is safe (and why) to use dendroclimate data to address the issue of long-term
     variation in temperature.

     Please don't construe my suggestions or comments as pro/con dendro, but rather just as
     someone who wants the truth - whatever it is - to be communicated clearly, and as best
     we know it. But, I do think that if Richard is suspect, dendro has a real problem. He
     doesn't have a personal bias in this, and is clearly trying harder than most to
     understand what's really going on with climate and the proxies.

     Effort now might save time later.

     Also, are you both going to be at the Swiss mtg in June? We really have to get this all
     ironed out better before the next (last) draft of the IPCC AR4.

     Thanks, Peck

     --

     Jonathan T. Overpeck

     Director, Institute for the Study of Planet Earth

     Professor, Department of Geosciences

     Professor, Department of Atmospheric Sciences

     Mail and Fedex Address:

     Institute for the Study of Planet Earth

     715 N. Park Ave. 2nd Floor

     University of Arizona

     Tucson, AZ 85721

     direct tel: +1 520 622-9065

     fax: +1 520 792-8795

     [1]http://www.geo.arizona.edu/

     [2]http://www.ispe.arizona.edu/

--

   Jonathan T. Overpeck
   Director, Institute for the Study of Planet Earth
   Professor, Department of Geosciences
   Professor, Department of Atmospheric Sciences

   Mail and Fedex Address:
   Institute for the Study of Planet Earth
   715 N. Park Ave. 2nd Floor
   University of Arizona
   Tucson, AZ 85721
   direct tel: +1 520 622-9065
   fax: +1 520 792-8795
   http://www.geo.arizona.edu/
   http://www.ispe.arizona.edu/

References

   1. http://www.geo.arizona.edu/
   2. http://www.ispe.arizona.edu/

