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RS (stomatal resistance) output variable in wrfrst files over Urban grid cells are non-sensical

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The stomatal resistance is output in wrfrst files (RS) (although it is called surface resistance in the file, which is slightly confusing).

If you have a look at the RS variable, the values range from a few thousand to sometimes 1e12.
I had a good look at this, and the very large values of 1e8 to 1e12 are always over urban grid cells.

It really does not make much sense to have stomatal resistance defined over an urban grid cell (i.e., non vegetated).

I assume this is of no actual consequence, as RS is only used in canopy respiration routines, which should not be called over urban tiles/grid cells.

It would be good however, if RS outputs over urban grid-cells are set to missing? So we do not have these very large 1e12 values. Perhaps the developpers might want to consider this.

Kind regards
The WRF modeling system doesn't allow missing values. You are right that rs over urban grid cells makes no sense. It has no consequences.