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UCM MODIS landuse

PostPosted: Thu Jun 15, 2017 11:10 am
by samuelfung50
Hello all,

I am using MODIS data for simulation and running with UCM, I have tried to alters the AH in URBPARM.TBL and compare the difference. I found that there were no difference in rainfall and even 2m Temperature.

I suspect that the UCM cannot find the urban area. Is it a must to change the MODIS 21 categories data to 33 categories? If yes how can I do so?
I have look up some of the forum posts but there is not given a solution, like:
(the link provided in the solution is dead)

Thank you so much for all of your time and energy!!


Re: UCM MODIS landuse

PostPosted: Fri Jun 16, 2017 12:29 pm
by samuelfung50
I executed geogrid.exe by using the MODIS data to generate "" first

Then I have modified "".

I have changed the land use (LU_INDEX) from 13 to 31, to assign all of the urban land use to be low-residential,
and I have also change the land use fraction (LANDUSEF) by moving the fraction in column 13 to column 31.

Finally, I have also modify the global attribute of (NUM_LAND_CAT) from 24 to 33.

However, when I execute metgrid.exe, it gives out an error:
"ERROR: Couldn't open file ./ for input."

I have already tried for a week and got stuck by the land use data. Hope there is anyone can solve the problem, thank you very much!!


Re: UCM MODIS landuse

PostPosted: Sun Jul 30, 2017 2:30 am
by wrf_alvin
Normally, it should work by simply changing the num_land_cat (number of land use category for MODIS) in the namelist.input as stated here: ... tween_USGS

The modules automatically adjusts the LU_INDEX corresponding to MODIS based on the num_land_cat parameter. I guess this will also depend on the WRF version you are using.