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Unrealistic TSK in WRF version 3.7 with UCM (LU_INDEX=33)


New member
Dear all

I am trying to do WRF simulations using V3.7.1 with UCM (LU_INDEX=33).
I found unrealistic TSK in the smallest domain, although it occurs one or several meshes.
Then, I checked the boundary conditions associated with heat balance equation related to the mesh with unrealistic TSK.
However, the boundary conditions seem no problem.
I am here to attach the distributions of TSK in the smallest domain, and the problem is one location which have significantly low surface temperature.
The simulation period is winter season (January in 2019) and even in winter, it is very unreasonable that the surface temperature can reach -20 ℃ in the Kantō region in Japan,
because there are only several days with the air temperatures under zero in winter season.
How can I solve the problem?
Should I take more greater domain or run with shorter time intervals (54 seconds now. there are 4 domains)?


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This is an issue in physics. Debugging problems in old WRF versions is no longer supported. Would you please switch to newer version of WRF and see whether the problem still exists? thanks.
Hi Chen

is it possible to use low version WPS (V3.7.1) when running newer version of WRF (V4.3)? Because we modified the program of WPS (V3.7.1) to read the local land use data.
No, I don't think so. This is because the vertical corordinate of WRF is changed since version 4.
I would suggest that you incorporate the changes you made in WRFV3.7.1 to WRFV4.3.