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Forcing surface winds

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yhwong

New member
Hi,

I am trying to figure out how I can force surface winds in WRF SCM. However, I can't find a variable that represent surface winds in WRF. There are the variables U10 and V10 (winds at 10m), but they seem to be diagnosed, so forcing them doesn't seem right. I am new to this so please correct me if I am wrong, but I think the surface winds are needed for surface flux calculations in the surface schemes? I looked into the code for surface schemes, but it seems like they simply take u_phy and v_phy (U and V at mass point) as inputs, and use u_phy at first model level as the wind input. Is that what WRF is doing? It seems odd that there are no variables for surface winds, could someone enlighten me?

Thank you very much for any thoughts or ideas you can provide!
 
U10 and V10 are diagnostic variables computed in sfclay scheme. Surface friction stress is calculated in sfclay scheme, while sensible and later heat flux are calculated in land surface model. Please take a look at the file below, which describes in detail how the model works:
http://www2.mmm.ucar.edu/wrf/users/tutorial/201907/dudhia_physics.pdf
 
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