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what else input data for sf_urban_physics

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Dear Colleagues,

I would like to know whether there is a need to interpolate external data for the physics options of sf_urban_physics?

Urban Surface (sf_urban_physics – replacing old switch ucmcall):
a. Urban canopy model (1): 3-category UCM option with surface effects for roofs, walls, and streets. In V3.7, a green roof option is added.
b. BEP (2). Building Environment Parameterization: Multi-layer urban canopy model that allows for buildings higher than the lowest model levels. Only works with Noah LSM and Boulac and MYJ PBL options. New in Version 3.1.
c. BEM (3). Building Energy Model. Adds to BEP, building energy budget with heating and cooling systems. Works with same options as BEP. New in Version 3.2.

Looking forward to hearing from you soon. Many thanks.

Best wishes,
I don't think you need to interpolate any data for use in urban physics. All the required data are provided by WRF.
Hi Chen,

Thanks for your prompt reply. But for the internal files, in addition to namelist.input and namelist.wps, for example, I think maybe I need to change some parameters in URBPARM.TBL?

I attached the file for your check.

Best wishes,


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I am confused here. What is your question? URBPARM.TBL is available in WRF (WRF/run).Surely you can modify some parameters in this file for your specific case, but these modifications must be reasonable.
Dear Ming,

Sorry for the confusion. Please allow me to explain my question:

I ran urban canopy model (option1) and building environment parameterization (option2), but I am not sure whether there is a need to modify the other WRF internal configuration files in addition to namelist files. By only changing the options of sf_urban_physics, my simulation results with nonurban (option0), urban canopy model (option1) and building environment parameterization (option2) have no obvious difference. I hereby suppose that I may make mistakes during the setting process.

Hope you could help with this. Many thanks.

Best wishes,
Hi Stella,
There is no need to provide extra data when you turn on urban physics module in WRF. But I guess you should pay attention to geo_em files and make sure you have detailed information of urban landuse type. If not many grids are specified to be urban type in your domain, then the results with and without urban physics should be similar. Another possibility is that, those parameters specified in URBPARM.TBL are empirical and one should make necessary adjustments based on one's specific case.
Please take a look at the website and hope you can find some helpful information here: