Dear Martin > (1) Grid cells have a temporally varying sea-ice fraction, and a mean is > wanted over the sea-ice area. > > Is this a correct cell_methods formulation: > "time: mean where sea_ice area: mean where sea_ice"?
The where construction is only provided in CF1.6 for area fractions, not time fractions (section CF 7.3.3). I think the method is first to average at each time over the sea ice area, and then make a time mean. The second operation does not have to know about the sea ice, so the cell_methods is area: mean where sea_ice time: mean > (2) Grid cells which sometimes have convective cloud, and a mean is wanted > over the times when there is a cloud in the cell. The variable to be averaged > is, in this case, the minimum over the cell of the convective cloud base. > > Is this the correct cell_methods: > "time: mean where convective_cloud area: minimum"? > > In the first case the first case "mean where sea_ice" refers to the portion > of grid cells have sea_ice, in the 2nd "mean where convective_cloud" would > refer to whole cells ... is this OK? Again, where is not for times. Also convective_cloud is not in the area-type table, though it could be added I expect. I think I'd put area: minimum time: mean (when convective cloud present) where the parenthesis indicates an optional unstandardised comment. Best wishes Jonathan _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
