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Can I use land use data which contains only 1 category in WRF-UCM?

ZHAO

New member
Good morning WRF Community!

I want to run a WRF model with urban canopy model on. To do this, I set the sf_urban_physics=1 in namelist.input. However, I can only offer traditional land use data to the WRF model, which means I have only 1 urban category. Now I am wondering that does it work to research on urbanization? I am afraid that sf_urban_physics=1 and sf_urban_physics=0 will get the same for the simulation results (wrfout).

Thanks a lot for your time.
 
In both USGS and MODIS landuse datasets, urban is specified by a single number (1 in USGS and 13 in MODIS). If urban landuse does exist in your model domain and can be well resolved based on the resolution of your case, then sf_urban_physics=1 will activate urban canopy module and describe physics over urban area. In this case, sf_urban_physics=1 and sf_urban_physics=0 should yield different results.
 
Thank you a lot for your quick reply! It does solve my question. I also want to ask in this case (we use wrf-ucm using only 1 category) how should I set urban parameters such as building height & anthropogenic heat? Are there any reference values or how should I determine the parameters?
 
These values are given in URBPARM.TBL.
I suppose you can change the values based on your case. Note that these default values given in WRF are highly experimental, i.e., they are determined from data collected at a few sites and may not well represent the situation in your case.
 
These values are given in URBPARM.TBL.
I suppose you can change the values based on your case. Note that these default values given in WRF are highly experimental, i.e., they are determined from data collected at a few sites and may not well represent the situation in your case.
Thanks for your explanation.

There are three urban categories in URBPARM.TBL, i.e., Low density residential, 2) High density residential, and 3) Commercial. However, I only have one urban-type when using USGS. I wonder how did WRF-Chem deal with the proportion of these three urban categories? Because I want to modify the anthropogenic heat flux factors in this table based on the database I collected for my case. That database is for the whole city, without specific information on different urban categories. How should I modify the URBPARM.TBL?

 
Ying,
Please start up a new thread and make it clear the question is related to wrf-chem. Otherwise the chem people may not be aware you have this question since it is "buried" in an old thread unrelated to wrf-chem.
 
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