Dear Lars When you compute the third operation (the range over climatological months) you collapse the time axis to size 1, so it no longer indicates that it was months. It might previously have been days, 5-day periods, or anything else. I think this case could be dealt with by the proposed (but not agreed) con- vention for multiple processing of axes in cf-trac.llnl.gov/trac/ticket/82. Something like
time: mean within years (period: 1 month) time: mean over years time: range might work. Best wishes Jonathan ----- Forwarded message from Bärring Lars <lars.barr...@smhi.se> ----- > Date: Fri, 13 May 2016 14:09:25 +0000 > From: Bärring Lars <lars.barr...@smhi.se> > To: Jonathan Gregory <j.m.greg...@reading.ac.uk>, "cf-metadata@cgd.ucar.edu" > <cf-metadata@cgd.ucar.edu> > Subject: RE: [CF-metadata] climatological statistics --- climate indices > > Dear Jonathan, > > > > But how about common continentality indices based on the annual range of > > > monthly mean temperatures? > > > Is there a "within months" such that the cell method for the basic > > > element of the continentality index would be "time: mean within months > > > time: range within years" ? Or is there another solution? > > > Climatological stats can be described for the annual cycle. The > > climatological monthly mean temperature would be "time: mean within years > > time: mean over years", and you would use the climatological time bounds to > > indicate the start and end of months (or other portions of the annual > > cycle). > > This would produce twelve climatological monthly values (for each location). > > Do you mean you then apply a third operation to compute the range of these > > twelve values? > > Yes, exactly. > > And, just to complete the picture, possibly even a to apply fourth operation > to calculate a climatological average over e.g. 30 years. In practice, this > is of course much simplified if one uses monthly mean temperature data as > input because the operations that is actually performed would be described > by the cell method "time: range within years time: mean over years". But this > would be an incomplete description of the data. > > Kind regards, > > Lars > > > ----- End forwarded message ----- _______________________________________________ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
