cc: rabetts@meto.gov.uk date: Fri, 02 Feb 2001 14:40:35 +0000 (GMT) from: Simon Tett to: Eduardo.Zorita@gkss.de (CC'd to all and sundry for their thoughts!) Hi Eduardo, sorry about the delay in responding. I've just moved jobs within the Hadley centre so have been a little snowed under. In a way your delay is good news! It means that it is still possible for us to do parallel experiments. Do you think that worth while? Tom Crowley is (I hope) merging together his volcanic forcing timeseries with that of Sato et al (I sent him some numbers..) to produce I hope a timeseries from at least 1500. When we last talked he thought he could use some Antarctic data to give "global" estimates. Ricahrd Betts, one of my colleagues, is sugesting that we use land surface changes for which he has got hold of a dataset. Is this something you wish to contemplate doing? I am also contemplating taking account of (the relatively small) orbital changes in the experiments. Is this something you wish to contemplate doing as well? Simon >>>>> "Eduardo" == Eduardo Zorita writes: Eduardo> Dear Simon, Eduardo> sorry for my late answer, I have been out of town. Eduardo> Actually we have not started that integration yet. We have had unexpected problems Eduardo> to "adapt" the ECHAM4 fortran 77 version to the f90 compiler. This work is done Eduardo> at the DKRZ in Cubasch group and Eduardo> proved to be more complicated than previously thought. So, it was been decided to Eduardo> develop a truly fortran 90 version of ECHAM4. This work is under way and Eduardo> the DKRZ schedule would be something like mid february. Eduardo> For the forcing factors since year 1000 BP, we were planning to use the Eduardo> data contained in Crowly (Science, 270), especially what the estimates Eduardo> of volcanic forcing are concerned. They are biased towards Northern Hemisphere Eduardo> eruptions, but perhaps this is the best we can get at this moment. Eduardo> Concerning solar variability, we had several options for the period 1000-1500, Eduardo> in which the estimations deviate somewhat stronger. I would tend to take Eduardo> the Be10 measurements from Bard et al Tellus B 52, 985 (2000). Eduardo> But we are open to new suggestions, since your group has more experience Eduardo> than ours. -- Dr Simon Tett Climate Research Scientist Met Office Hadley Centre Climate Prediction and Research London Road Bracknell Berkshire RG12 2SY United Kingdom Tel: +44 (0)1344 856886 Fax: +44 (0)1344 854898 E-mail: sfbtett@meto.gov.uk http://www.metoffice.gov.uk