NCAR / ccpp-physics

GFS physics for CCPP
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Add option to use a new prognostic closure in saSAS and GFS shallow convection. #890

Closed lisa-bengtsson closed 2 years ago

lisa-bengtsson commented 2 years ago

Description

This update introduces a new prognostic closure based on a moisture budget for the convective updraft area fraction (replacing constant value 0.03). It also has the option to use a stochastic cellular automaton for enhanced organization and replaces the code under the ca_closure flag.

Solution

The prognostic updraft area fraction source and sink terms are computed in a new routine which is called from both deep and shallow convection. The area fraction is carried as a tracer, similar to tke, and is advected but not diffused in the vertical.