Vertical diffusion matrix is already built in the OperatorDiagnosis and RegionalExtraction Programs
Routines are in place in the TracerStorage_Class to give the action of the vertical diffusion operator; this can be used to construct forward or backward difference schemes
CPP Flags are in place to enable/disable this feature.
What would be needed
Determine a valid range of diffusion coefficients and vertical grid spacing to estimate diffusive CFL criteria
If implicit vertical diffusion is desired, an efficient matrix inversion scheme is needed - may be able to exploit water column independence for vertical diffusion operator. Such a scheme would permit the inversion of decoupled water column matrix-vector systems for parallelism.
In this discovery project, it was found that
TracerStorage_Classto give the action of the vertical diffusion operator; this can be used to construct forward or backward difference schemesWhat would be needed
Follow up issues will be needed.