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How to plot spatial distribution of roughness length Z0

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Dear WRF-experts,

I cant seem to find any tutorial online on how I can plot the roughness length (Z0).

This is also not located in the geo_em files.

Any ideas on how to plot this?

I'll appreciate any help on this.


Thank you for the fast response.

I want to plot the USGS and MODIS roughness lengths before running WRF.

Is it the one from VEGPARM.TBL?
But Im confused. There are four in this TBL:

USGS (with Z0min and Z0max)
MODIFIED_IGBP_MODIS_NOAH (with Z0min and Z0max)
USGS-RUC (Z0 only)
MODI-RUC (Z0 only)

Which one should I use here?

If I use the first two, is it correct to take the average of Z0min and Z0max to get the Z0?
I apologize for the delay. I wanted to run this by our physics specialist to ensure I was giving the appropriate response.

The roughness length is computed only when WRF starts running because it uses Z0min and Z0max and the seasonally varying VEGFRA, so it varies slowly with time, according to the season. Over water it varies with wind speed. ZNT in the output shows its latest value.