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Land cover LU_INDEX changed after wrf.exe run --WRF V3.9.1.1

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C

Chang_Shu

New member
Hello,

We are doing a 1 km resolution 3 domain nested simulation for the Ottawa area.
However, we found the LU_INDEX in the WRF output file came to be large pixels, which is different from that in the geo_em.d03.nc and met_em.d03.*.nc files.
Please find the plots for LU_INDEX in geo_em, met_em and wrfout files below.

LU_INDEX in geo_em.d03.nc
LU_INDEX_geo_em.PNG

LU_INDEX in met_em.d03.*.nc
LU_INDEX_met_em.PNG

It seems reasonable with fine land cover resolution in the above two figures.
So I suppose the preprocessing programs (geogrid.exe and metgrid.exe) are running well.

But after wrf.exe run, the LU_INDEX changed to large pixels:
LU_INDEX in wrfout.d03.*.nc
LU_INDEX_wrfout.PNG

The static geographical data we are using is the MODIS default configuration.
As specified in the namelist.wps file:

Code: 
&geogrid
 parent_id         =   1,   1,    2,  
 parent_grid_ratio =   1,   3,    3,   
 i_parent_start    =   1,   99,   57,  
 j_parent_start    =   1,  106,   73,   
 e_we              = 276, 250,  391,  
 e_sn              = 296, 283,  364, 
 geog_data_res     = 'modis_30s+2m','modis_30s+30s','modis_30s+30s',

The version of the WRF we are using is WRF V3.9.1.1.


Could anyone please let me know if it is normal that the LU_INDEX distribution changes in the WRF output file?
And how can we avoid this problem in WRF V3.9.1.1?

Thanks!
 
Hi,
Can you also attach your namelist.input file and let me know which type of input data you are using? Thanks!
 
Hello, kwerner
Thanks for your reply!
Please find the namelist.input in the attachment.
We are using NCEP North American Regional Reanalysis (NARR) ds608.0 as inputs.
 

Attachments

  • namelist_copy.input
    4.9 KB · Views: 67
Thanks. Can you change "surface_input_source" to 3 and re-run real.exe and then wrf.exe, and let me know if that makes a difference?
 
Hello,
I have tried to change surface_input_source = 3. But it did not work.

I changed the line
input_from_file = .true.,.false.,.false.,
to
input_from_file = .true.,.true.,.true.,

Then the result seems good!
Thanks for the help!

Chang
 
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