date: Tue Jan 4 15:57:23 2005 from: Phil Jones subject: Re: odds of keep getting record warm years to: "Stott, Peter" Peter, The only person who's tried to do something like this is Tom Karl - some years ago. I recall Tom Wigley not thinking much of it. Tom had a paper in GRL in 2000. Wigley, T.M.L., 2000: ENSO, volcanoes and record-breaking temperatures. Geophys. Res. Letts. 27, 4101-4104. This was more to do with record breaking months though - in sequence. This is what Tom Karl's was about too. Tom W's problem was El Nino effects on the monthly timescale. I don't think it is as quite as straightforward as you say, but that is where I'd start. I think you also need to assume a trend as well as an AR process. Maybe they are the same. It would be worth sorting out as the statistic won't be that good next year. The year that messes it up is 1996. 1990 is in instead. To get rid of 1990 requires other years to drop out as it is about 6th or 7th warmest, and 1996 will still be in next 10 at end of 2005. So it won't be so good in Dec 2005 ! Cheers Phil At 14:11 04/01/2005, you wrote: Hi Phil, Have you ever calculated the odds of keep getting years in the warmest 10 on record, eg 9 of the 10 warmest on record being in the last 10 ? Henry Derwent is asking about this - I'm aware of what Tom Karl has done but not sure what else - presumably it's a relatively easy job to fit an AR model to the data and then calculate probabilities. Peter -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Dr. Peter Stott Climate Scientist Met Office Hadley Centre for Climate Prediction and Research (Reading Unit) Meteorology Building, University of Reading, Reading RG6 6BB Tel: +44 (0)118 378 5613 Fax: +44 (0)118 378 5615 Mobile: 07753880683 E-mail:peter.stott@metoffice.gov.uk [1]http://www.metoffice.gov.uk NOTE WILL ALSO BE AT EXETER PART OF EACH WEEK ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Prof. Phil Jones Climatic Research Unit Telephone +44 (0) 1603 592090 School of Environmental Sciences Fax +44 (0) 1603 507784 University of East Anglia Norwich Email p.jones@uea.ac.uk NR4 7TJ UK ----------------------------------------------------------------------------