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cloud fraction

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New member

I was wondering if MPAS has a variable to represent the presence of clouds, like fractional cloud coverage. Can I use the variable cloud water mixing ratio, qc > 0 as the presence of cloud?

Thank you.

Hi Kemal:

The variable that you are looking for is "cldfrac" which is the horizontal cloud fraction used in the long-wave and short-wave radiation codes. They are two options to calculate cldfrac "cld_incidence" or "cld_fraction" which are set using the namelist parameter "config_radt_cld_scheme" (also, see Users' Guide). The default option used in the "mesoscale_reference" and "convection_permitting" suite is "cld_fraction" that computes the cloud fraction as a function of the cloud condensates and relative humidity following Xu and Randall (1996).
Hope this helps,