cc: "Myles Allen" , "Knutti Reto" , "Stott, Peter" , "Gabi Hegerl" , "Zwiers,Francis [Ontario]" , "Tim Barnett" , "Hans von Storch" , "Phil Jones" , "David Karoly" , "Toru Nozawa" , "Ben Santer" , "Daithi Stone" , "Nathan Gillett" , "Michael Wehner" , "Xuebin Zhang" , "Tom Knutson" date: Thu, 16 Apr 2009 12:32:03 -0700 (PDT) from: "Tim Barnett" subject: Re: proposal-unrelated curiosity to: "claudia tebaldi" claudia...i was asked to comment on the paper; a tepid comment at best. they just matched a couple of trends. they did not do a heat budget as they should have. so they maybe right, they maybe wrong. will have to wait until the problem is done properly. and as i remember they did no formal D&A. hope this helps, tim > Hi again > > this time a personal inquiry: someone just sent me this paper about > SST variability in the tropical Atlantic, where it is claimed that a > large portion of the variability is related to aerosols (dust from > West Africa and volcanic eruption). I was curious to hear from any of > you that may have seen this and may want to comment. From the > abstract, they claim that 69% of the 'recent upward trend' (from > 1980ish) is explained by aerosols forcing, but then they perform a > sensitivity analysis to parameters in their model and admit to > non-robustness of this particular result, if I understand > correctly...There is no detection/attribution formal methodology at > play, from what I can tell; they are also apportioning the source of > variability between strato- and tropospheric aerosols and it is not > clear to me how they do that...am I too quick and judgmental, or is > this actually a fairly weak result? > > Thanks for any pearl of wisdom you feel like sharing -- I don't know > enough about a lot of the issues involved here, so I'm trying to > understand and I thought I exploit my new position as IDAG > hopefully-honcho-to-be by asking the experts. > > c > > > -- > Claudia Tebaldi > Research Scientist, Climate Central > http://www.climatecentral.org > currently visiting IMAGe/NCAR > PO Box 3000 > Boulder, CO 80305 > tel. 303.497.2487 >