Hi Heiko,
I support your proposal to add "low_cloud_area_fraction",
"low_cloud_area_fraction", and "high_cloud_area_fraction".
Just for information for all:
(1) There is something called "high cloud" etc as Heiko says.
(2) It's misunderstanding that whatever "cloud" located in high layer
becomes high cloud.
(3) By that misunderstanding parameters like "low cloud cover" are once
noted deprecated in GRIB edition 2.
But WMO expert team now understood proper meaning of parameter, so it will
be corrected this November.
http://www.wmo.int/pages/prog/www/ISS/Meetings/IPET-DRC_Melbourne2011/Documents/IPETDRC-III_Doc2-2_3_AccumulationUnits.docBest Regards,--Eizi TOYODA----- Original Message -----From: "Heiko Klein" <Heiko.Klein at met.no>To: <cf-metadata at cgd.ucar.edu>Sent: Wednesday, April 25, 2012 6:49 PMSubject: [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 bycloud_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 sat
isfying: Either Iadd some dummy sigma-values, which will look like I have a model with justthree 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 beexpressed 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 thestandard_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> CF-metadata at cgd.ucar.edu>
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Received on Wed Apr 25 2012 - 04:55:12 BST
