cc: Keith Briffa date: Tue, 19 Jul 2005 09:33:55 +0200 from: Eystein Jansen subject: Ad: Re: thoughts and Figure for MWP box to: Tom Crowley , Jonathan Overpeck Hi, I think both Keith's and Tom's emails highlight some of the problems when going from hemispheric scale reconstructions to plots of individual records or regional groupings of them. First I agree with Keith concerning the reality of a warmer MWP on average, we cannot leave the impression that there was no warmth when making the argument that it had lots of geographical and temporal diversity. We should make it clear the distinction between reconstructions and individual series. Concerning Tom's point about which series to include, I see the point of avoiding oversampling one region, but there is a problem as soon as we start bringinging indivifual series together to make a regional composite. We will undoubtedly be attacked for not showing all available data, but can come around this by stating yhat the purpose is not that of a reconstruction, rather to drive home the point of geograhy/temporal diversity through typical series. I would also concur that we should omit the Chesapeak series, if the data is Cronin's Mg/Ca data. There are too many uncertainties on salinity influences on this proxy, plus it is radiocarbon based. Both here and in the text the lack of low lat series needs to be pointed out. I think we should stick to the agreement from our conf.call and only show the 800-1300 AD interval. This will avoid confusion wrt the reconstruction fig. in the main chapter. Cheers Eystein