cc: Keith Briffa , cddhr@giss.nasa.gov, Fortunat Joos , joos , Ricardo Villalba , lean@demeter.nrl.navy.mil, Eystein Jansen , Piers Forster date: Wed, 5 Jan 2005 21:09:12 -0500 (EST) from: hegerl@duke.edu subject: Re: Chapter 2 Forcings - the latest on solar from Judith Lean to: Jonathan Overpeck Hi everybody, Thanks JOnathan for sending this, we'll have a look at it. Our chapter is out with the LAs for a last check right now, but so far, we have only a little bit on solar signals. They are detectable in some approaches and not in others, appear possibly enhanced in some (mostly 20th century) and possibly diminished in others (particularly for last millenium), so there is no clear picture. Apart from that even if solar were enhanced, it could not explain the 20th century warming. Does this sound ok with you? If yes, lets do some more coordination once the zeroth draft is submitted, does that sound ok? Happy new year to everybody Gabi On Wed, 5 Jan 2005, Jonathan Overpeck wrote: > Hi gang - attached is the hot off the press view on solar and > volcanic forcing from Chap 2. The purpose of my email is to start the > process of making sure we (at least chapters 2, 6 and 9) have > compatible perspectives on the isses, particularly solar. > > Keith is the chapter 6 lead (Ricardo the second) on the last 2000 > years (section 6.3.2.1), and David and Fortunat on climate forcing > (sec 6.5.2). David and Keith are doing our last 2000 model eval > section (sec 6.4.3.2). In order to help Keith and Ricardo get their > section down to size, we've suggested that they move discussion of > the forcing to 6.5.2 (David and Fortunat need to finish this). Keith > has not yet responded that this is ok, but let's go with it until he > gets back into the mix. > > I've also sent this to Gabe (Happy New Year Gabe!). > > I suggest that the likely email discussion of the solar issue > (perhaps volcanic will be a bit hot too) is cc'd to all on this > email, plus any others that we think are key. I'm not sure Judith is > on email right now, but she's on the list too for obvious reasons > (Piers is the CLA coordinating this for Chap 2, so he's on too). > > My personal take is that much of what has been done wrt to solar in > the paleo literature is now more suspect, but I think Fortunat in > particular might have some sage comments on this. The main thing is > that we don't ignore the latest work that suggests that solar forcing > is more subdued than often thought. > > Debate? Thanks Chap 6 authors for coordinating with the other > chapters (e.g., 2 and 9) on this issue. > > Best to all, Peck > > > > >X-Sieve: CMU Sieve 2.2 > >From: "Piers Forster" > >To: "'Jonathan Overpeck'" > >Subject: RE: Early draft: Natural Forcings > >Date: Wed, 5 Jan 2005 11:07:01 -0000 > >Thread-Index: AcTyk5zrDHPy1i6XQ6OYxcStlz6FtwAgtapg > >X-Scanner: exiscan *1Cm919-00056N-00*XIzGZ/vmCRE* (The University of Reading) > >X-Virus-Scanned: by amavisd-new at email.arizona.edu > > > > > >Yes, please do send it... > >This is what we have at the moment > >Cheers > > > >Piers > > > > > > -- > 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/ -------------------------------------------------------------------- Gabriele Hegerl Dept. of Earth and Ocean Sciences, Nicholas School of the Environment Duke University, Durham NC 27708 phone 919-684-6167, fax 919-684-5833 email: hegerl@duke.edu http://www.eos.duke.edu/Faculty/hegerl.html ---------------------------------------------------------------------