Folks: The current definition for "atmosphere_optical_thickness_due_to_cloud" in the current standard name table is:
The optical thickness is the integral along the path of radiation of a volume scattering/absorption/attenuation coefficient. The radiative flux is reduced by a factor exp(-optical_thickness) on traversing the path. A coordinate variable of radiation_wavelength or radiation_frequency can be specified to indicate that the optical thickness applies at specific wavelengths or frequencies. The atmosphere optical thickness applies to radiation passing through the entire atmosphere. The specification of a physical process by the phrase due_to_process means that the quantity named is a single term in a sum of terms which together compose the general quantity named by omitting the phrase. There are other "atmospheric_optical_thickness_due_to_<process>" standard names in the table, and they all have a clarifying sentence about the "<process>" part. The definition for "atmosphere_optical_thickness_due_to_cloud" does not have a clarifying sentence for what a cloud means. Is this a mistake ? If so, maybe the following changes should be made to the standard name table: (1) Add a standard_name "atmosphere_optical_thickness" and use the current definition for "atmosphere_optical_thickness_due_to_cloud" as identified above. (2) Change the definition of "atmosphere_optical_thickness_due_to_cloud" to be: The optical thickness is the integral along the path of radiation of a volume scattering/absorption/attenuation coefficient. The radiative flux is reduced by a factor exp(-optical_thickness) on traversing the path. A coordinate variable of radiation_wavelength or radiation_frequency can be specified to indicate that the optical thickness applies at specific wavelengths or frequencies. The atmosphere optical thickness applies to radiation passing through the entire atmosphere. "Cloud" means the component of extinction owing to the presence of liquid or ice water particles. The specification of a physical process by the phrase due_to_process means that the quantity named is a single term in a sum of terms which together compose the general quantity named by omitting the phrase. very respectfully, randy
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