date: Fri, 14 Dec 2007 17:22:29 +1100 from: David Thompson subject: the paper.... to: Phil Jones , John Kennedy Dear Phil and John, Thanks much for the quick and helpful comments... In the next version I'll include more details on the analysis procedure... hopefully that will clarify how the volcano results were calculated. As for the negative anomalies ~8-10 years before the eruption dates: they reflect the impact of the trends in temperature on the composite, not just the impact of El Chichon prior to Pinatubo. (You don't see the negative blips if you only go +/- 5 years). In the text I used the spurious negative chunks to motivate the detrending. I agree with Phil that the volcano text is still a little rough. And I like the idea of showing the results for each volcano separately. I've recently shown the results to a few folks heavily involved in the last IPCC, and they've suggested we consider a pair of companion papers: a longer JCL paper which focuses on the volcanos and provides the details of the filtering methodology; and a short, punchy Nature paper which focuses on the step in 45. I suppose it's possible the step in 45 could get lost in a longer volcano paper, and apparently the results clarify why the IPCC models are unable to capture SST variability in the middle of the 20th century... if you have strong thoughts on this, please let me know. And if you have any additional comments that come to mind over the next couple weeks, please send them along. I'll get a next draft to you soon after the New Year... it will incorporate all your ideas, will provide the analysis details, etc ... Thanks again, Dave -------------------------------------------------------------------- -------------------------------------------------------------------- David W. J. Thompson www.atmos.colostate.edu/~davet Dept of Atmospheric Science Colorado State University Fort Collins, CO 80523 USA Phone: 970-491-3338 Fax: 970-491-8449