date: Mon Mar 25 13:58:37 2002 from: Tim Osborn subject: Fwd: Re: recommendations for Tim to: "Gabriele C. Hegerl" Gabi - Phil has asked me to send the error bars for our reconstruction (as published in JGR in 2001, though also shown in the Jones et al. Science 2001 paper). Sorry, but I won't have time to do this before Easter - will try next week. Regards, Tim X-Sender: f028@pop.uea.ac.uk X-Mailer: QUALCOMM Windows Eudora Version 5.1 Date: Wed, 20 Mar 2002 16:56:22 +0000 To: t.osborn@uea.ac.uk From: Phil Jones Subject: Fwd: Re: recommendations for Tim Tim, Here's a reminder about sending Gabi the Briffa et al (2001) error bars. Cheers Phil Date: Wed, 20 Mar 2002 09:41:58 -0500 (EST) From: "Gabriele C. Hegerl" Sender: hegerl@duke.edu To: Phil Jones Subject: Re: recommendations for Tim X-Virus-Scanned: by amavisd-milter, Duke University ([1]http://amavis.org/) HI Phil, I'll talk with Tom through the paleo indices once more, and find out if we can also try to make a growing season or summer halfyear one (probably we'd have to leave a few out). I agree with you that it is good to reconstruct the thing the data reconstruct best, particularly after seing the different trends in summer vs winter in the instrumental data (some figure you showed). For Mike Mann, it would be particularly easy and SO MUCH more useful to do summer vs winterhalfyear! On another issue: I forgot what exactly you said how I can get the errorbars for the Briffa et al 2000 data - should I ask Keith, or is there a website to collect it from? Thanks in advance!! Greetings to England, did you hear about the Larson B shelf? I am sure the AAO people will have some airtime again soon ;) Gabi On Fri, 15 Mar 2002, Phil Jones wrote: > > Tom and Gabi, > On the paleo front, the issue I see as important is seasonality as > you know. The fact that > you get such good agreement may be due to the high correlation between > summer and > annual temperatures at hemispheric and global scales. In a paper with > Keith in The Holocene > in 1992 we showed the correlations between each month and the annual > average and values > were all above 0.85 if I remember correctly. Some of this is due to > common forcing but much > is due to common trends. Locally though (where the individual paleo > series come from) the > correlations are much lower. > I guess would like to stress with Ray that Mike Mann should show > his reconstructions > separately for winter and summer half years (say NDJFM and MJJAS). No > need to do all > four seasons, just extended winter and summer. Need to do these with > temperature > series that have the long term trends removed. Mike's work (summer vs > winter and with > trees and without trees) needs to be a whole lot more convincing that > annual is really > being reconstructed. Tim Osborn here will be doing some of this as part > of an EU project > (SOAP) we hope to hear about soon. > The point I'm trying to make is that the scaling you and I do to get > the long reconstruction > will always work because of the strong correlation between the growing > season and annual > temperatures at the largest of space scales. > Don't forget to send the long forcing time series when you get a chance. > > Cheers > Phil > > > > At 10:58 12/03/02 -0500, you wrote: > >Phil, > > > >thanks very much - I share your recommendation. > > > >On another matter Chris Miller has asked me to sit in on or join an ad hoc > >paleo working group, chaired I think by Ray Bradley, to help try focus > >some paleo aspects of his program. We meet next week at NCDC. If you > >have any recommendations for action I would be more than happy to hear > >them. My basic inclination is to focus on well-targeted sites that fill > >in crucial holes in coverage for the time span of the last millennium (I > >think the data analysis and syntheses side is progressing fairly well). > > > >Lastly, I think it would be really interesting to compare your long > >instrumental record with the tree ring density data to see whether they > >have similar trends in summer temperature. There may also be some data > >from eastern North America that could be helpful in that > >respect. Although your concerns about using mean annual calibrations are > >certainly valid I cannot understand how we can get such a good agreement > >between our linear model and the mean annual reconstruction if the latter > >is not to be believed. Our forcing time series have been independently > >developed and are I believe moderately robust, and there is certainly no > >ambiguity in why the model produces what it does. It is hard to believe > >that the very high correlations we obtain could result from chance alone. > > > >Please keep me posted on this and other aspects of your work. It was nice > >seeing you again, Tom > > > > > > > >>Dear Tom, > >> The principal recommendation I would have is to sort out the MSU > >> datasets between > >> Frank Wentz and John Christy. > >> > >> If this cannot be resolved then the recommendation would be for all > >> doing > >> detection to use both datasets to give an idea of the possible error. > >> > >> I think this is the HIGHEST category, so high that I won't give any > >> more. > >> > >> Cheers > >> Phil > >> > >>PS Mike Mann's paper to Science on reconciling boreholes didn't make it. > >>Just agreed to > >> review it for GRL. > >> > >> > >>At 10:39 07/03/02 -0500, you wrote: > >>>Hi All, > >>> > >>>It was good to see you all again and thanks again to Ben for organizing > >>>the meeting and Tim for all he has done. > >>> > >>>I suggest we need to think harder about what we recommend - this may be > >>>a rare opportunity for an independent group to put some thoughts down on > >>>the matter - not just as it applies to us or the U.S. - but with respect > >>>to the entire issue as it could possibly be addressed by international > >>>coordination (heaven forbid!) of funding agencies. > >>> > >>>I therefore volunteer to assist Tim in putting together any email > >>>recommendations you may make WITHIN THE NEXT TWO WEEKS. Your comments > >>>must be CONCISE an. Comments on priority should be included using, > >>>tentatively, the following categories -- VERY HIGH, HIGH, NEEDED > >>> > >>>Regards, Tom > >>> > >>>ps please check the mailing list to see whether anyone else should be > >>>included - I don't have Bill Pennell's email, for example. > >>>-- > >>>Thomas J. Crowley > >>>Nicholas Professor of Earth Systems Science > >>>Dept. of Earth and Ocean Sciences > >>>Nicholas School of the Environment and Earth Sciences > >>>103 Old Chem Building > >>>Duke University > >>>Durham, NC 27708 > >>> > >>>tcrowley@duke.edu > >>>919-681-8228 > >>>919-684-5833 fax > >> > >>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 > >>---------------------------------------------------------------------- ------ > > > > > >-- > >Thomas J. Crowley > >Nicholas Professor of Earth Systems Science > >Dept. of Earth and Ocean Sciences > >Nicholas School of the Environment and Earth Sciences > >Box 90227 > >103 Old Chem Building Duke University > >Durham, NC 27708 > > > >tcrowley@duke.edu > >919-681-8228 > >919-684-5833 fax > > 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 > ---------------------------------------------------------------------------- > > > -------------------------------------------------------------------- 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 [2]http://www.eos.duke.edu/Faculty/hegerl.html --------------------------------------------------------------------- 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 ----------------------------------------------------------------------------