e3afa375_on_and_or_cloud_microphysics____What
[When] 2004/09/30/00 [Who] Ferrier [What] 
Set RHsat in RADTN to RHgrd (0.967 for 32-km runs). This change is intended to increase the amount of grid-scale cloudiness based on the latest comparisons against the AFWA total product. Set STSD in RADTN to .02 rather than .01, which assumes a standard deviation of total grid-scale relative humidity of 2% Multiply the cloud optical depths by a factor of 0.5+max(0., min(0.5, cosz(i) ) ), which reduces the cloud optical depths by at most a factor of two starting at zenith angles larger than 60 deg. This change is intended to cut down on the large reduction in solar radiation passing through clouds at low sun angles.
Mesoscale Parallel Experiment Change Log for " Eta-32 with winter 2005 Eta change package, experimental changes to GFS radiation and/or cloud microphysics "
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