Hello Heiko, I don't have a strong opinion, but am just testing the water ...
I wonder how one would define these standard names so that they were correct for all uses, for example from a three layer model to the ISCCP datasets. In your example, would a model_level_number coordinate of [1, 2, 3] fit your needs, possibly with an auxiliary coordinate of ['low', 'medium', 'high']? Would we need a standard name for the auxiliary coordinate, or would a long name suffice? All the best, David ---- Original message from Heiko Klein (11AM 25 Apr 12) > Date: Wed, 25 Apr 2012 11:49:06 +0200 > From: Heiko Klein <[email protected]> > User-Agent: Mozilla/5.0 (X11; Linux i686; rv:11.0) Gecko/20120327 > Thunderbird/11.0.1 > To: "[email protected]" <[email protected]> > Subject: [CF-metadata] Standard_name for cloud-cover by phenomenon > > Hei, > > in grib, clouds are described as low, medium and high clouds, e.g. > 73,74,75. Those are described by phenomenon, e.g. > > high cloud type: Clouds of genera Cirrus, Cirrocumulus and Cirrostratus. > > low cloud type: Clouds of genera Stratocumulus, Stratus, Cumulus, etc. > > medium cloud type: Clouds of the genera Altocumulus, Altostratus, etc. > > (see > > In CF, this can currently only be expressed by > cloud_area_fraction_in_atmosphere_layer and a not very well defined > 'vertical' parameter, e.g. by sigma: > http://www.ecmwf.int/products/data/archive/data_faq.html#clouddefinitions > > > When translating from grib to CF, this is not very satisfying: > Either I add some dummy sigma-values, which will look like I have a > model with just three levels, or I use 3 variables, all with the > same 'standard_name="cloud_area_fraction"' which looses some useful > information. In both cases, the data-user will need to know > something which cannot be expressed by CF. > > > Looking at the page > http://cf-pcmdi.llnl.gov/documents/cf-standard-names/ecmwf-grib-mapping > there are mentioned 3 'standard_names' which are not in the > standard_name-table yet, and I propose to do so: > > low_cloud_area_fraction > medium_cloud_area_fraction > high_cloud_area_fraction > > in additon (though this is not in grib), I would like to add > fog_area_fraction (or surface_cloud_area_fraction). > > > Best regards, > > Heiko > > _______________________________________________ > CF-metadata mailing list > [email protected] > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata -- David Hassell National Centre for Atmospheric Science (NCAS) Department of Meteorology, University of Reading, Earley Gate, PO Box 243, Reading RG6 6BB, U.K. Tel : 0118 3785613 Fax : 0118 3788316 E-mail: [email protected] _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
