cc: m.hulme@uea date: Tue, 31 Oct 2000 14:14:08 +0000 from: Tim Mitchell subject: Re: quick questions to: Sari Kovats >Is that the mean of from 0100 to midnight or do we do something else fancy? Sari, You can define a day in whatever way you want! Usually that means 24h (!), but the start and finish moments may be done according to Greenwich Mean Time, local time, or whatever. The best way would be to match the data that you have for other variables. The everyday definition of a "day" starts the moment the clock strikes midnight, in which case, 00:00 would be your first measurement, and 23:00 your last. I am assuming that the data that you averaging is already a mean itself. An obvious example is that you cannot average the max wind speed in an hour over a 24h period to obtain the max wind speed in a day. Tim /// \\\ ( 0 0 ) ____oOO (_) OOo_________________________ Tim Mitchell post: CRU, UEA, Norwich, NR4 7TJ, UK email: t.mitchell@uea.ac.uk web: http://www.uea.ac.uk/~f709762 phone: +44 (0)1603 593161 (direct) fax: +44 (0)1603 507784 (office) __________________________________________