Dear Randy > The cell method "sum" is applied to the "time" and "y" and "x" coordinate > variables The reason "sum" is used for the "time" coordinate variable is > that the sensing of a region (i.e.cell) occurs over a several minute > period. The sensing associated with a particular observation/pixel in the > region (i.e. cell) happens in less than a second. Statistics associated > this cell in time are really an accumulation over the several minute > sensing period.
OK, I see. The observation is a formed from a sum. Nonetheless, is the geophysical quantity really a sum? Is it extensive in time? For instance, if conditions stayed exactly the same, and the time interval was made twice as long, would the reported value be twice as large? The units of aerosol optical depth do not suggest that it depends on the length of the time interval like, for instance, precipitation amount does. Best wishes Jonathan _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
