cc: t.osborn@uea.ac.uk date: Wed, 9 Apr 2008 15:07:04 +0200 from: Thomas Kleinen subject: Re: EGU presentations to: Keith Briffa Hi Tim and Keith, I've slept over it - yesterday I was too tired to actually finish them - and yes, that's basically what I am going to try to do. Not quite sure yet, how exactly, but probably along those line: 1) MOC slowdown high lat warming seems model dependent, doesn't appear in Palaeodata (since we have plenty in summer in Northern Scandinavia, we can definitely say we don't see that warming). If we ignore that warming, mid-latitude Atlantic would cool more than other areas if that was the case. 2) radiative forcing changes definitely are required to obtain right magnitude of cooling 3) negative NAO implies less cooling DJF Greenland / eastern Canada, we have indications that that is the case for that 1680-1710 (one qualitative point Canada, one quantitative Greenland), it therefore "appears likely" that that was the case 4) 1800-1830 can be explained by radiative forcing changes alone. generally desirable: More proxy data, especially winter and lower latitudes. That sounds a lot better to me, what do you think? Cheers, Thomas On Wednesday 09 April 2008, you wrote: > Hi Thomas > sorry was away in London yesterday - I agree - and also that this has > a rather disappointing negativity - s perhaps dress up with more > positive indication or emphasis on what would be required in ideal > situation ? cheers > Keith > > At 16:22 08/04/2008, you wrote: > >Hi Tim and Keith, > > > >I'm nearly done with my presentations, but I thought I should do a > >quick check > >with you... > > > >My basic message will be that we don't have enough data to prove or > > disprove any of the hypotheses, and that especially winter proxy data > > would be required to be able to do that. > > > >Is that all right with you? > > > >In Phil's session I'll give an overview over what we've done in the > > project, show the results obtained in the different experiments and then > > show (palaeo) data coverage for the timeframe in question. > > > >In the other session (that's the open session on Climatology and > >Palaeoclimatology, I had submitted it to past atmospheric circulation, but > >that session was apparently cancelled and my presentation moved over to > > the open session, I realised that only just now when I looked up the > > session title again) I'm going to focus on the nudging experiments. > > > >Still, the take home message will be the same in both sessions - we need > > more data to actually pin down a mechanism. > > > >So do you have any comments, should I change that slightly, any other > > ideas? > > > >Cheers, > >Thomas > > > >PS: I guess that's a more prominent session for the nudging presentation. > > Ah well, some extra publicity... Still it would be nice to be able to > > present slightly more positive findings. > > -- > Professor Keith Briffa, > Climatic Research Unit > University of East Anglia > Norwich, NR4 7TJ, U.K. > > Phone: +44-1603-593909 > Fax: +44-1603-507784 > > http://www.cru.uea.ac.uk/cru/people/briffa/