Hi, Many thanks for the prompt replies. I comment in text below.
> > Since the UV index is a standard quantity, it seems fine to me to give it > > a standard name of uv_index, or ultraviolet_index - which would be better? > > I don't think "surface" is needed unless it is sometimes reported at other > > levels - is it? As far as I know this is only reported at the surface. At least that is the original intention of it following WMO and WHO. In WMO context I have so far not seen anyone reporting this elsewhere than at the surface. Concerning whether to use uv_index or ultraviolet_index, both are fine to me. In my community is usually denoted UV index, but I do see the point made by Seth to avoid potential confusion between various communities. Thus, although I use the short form below, I would be happy with ultraviolet_index. > > I would assume that without qualification it would refer to the actual or > > forecast cloud cover. If you would like to provide it as dependent on > > cloud cover, this could be done by giving it a coordinate variable or > > scalar coordinate variable with a standard_name of cloud_area_fraction. If > > you prefer to indicate the cloudiness in the standard name, I think this > > could be done for clear-sky on the pattern of existing standard names as > > uv_index_assuming_clear_sky This sounds good to me. For complete cloud cover I would suggest to use uv_index_assuming_overcast to comply with WMO terminology. > > There aren't any existing standard names for complete or partial cloud > > cover. Complete cloud cover is well-defined and an "assuming" phrase > > could be agreed for that, I imagine. Does partial cloud cover have a > > precise definition? No, there is no good definition of this. It is usually used for any fractional cloud cover (1/8-7/8 in WMO terminology). In this context it refers to 4/8 (50%) cloud cover. Broken and scattered cloud cover is used in METAR reports and are better defined, but are not useful in this context as they are in a regime that divides the cloud cover in 5 classes - clear, scattered, broken, overcast and obscured. How about using something like uv_index_assuming_half_fractional_cloud_cover. If allowed in standard names, one could use either 50% or 4/8 instead of half. Essentially, I would then suggest the following names: ultraviolet_index ultraviolet_index_assuming_clear_sky ultraviolet_index_assuming_overcast ultraviolet_index_assuming_half_cloud_cover All the best Øystein -- Dr. Oystein Godoy Norwegian Meteorological Institute P.O.BOX 43, Blindern, N-0313 OSLO, Norway Ph: (+47) 2296 3000 (switchb) 2296 3334 (direct line) Fax:(+47) 2296 3050 Institute home page: http://met.no/ _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
