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Missing FRC_URB2D values over Cyprus using cglc-modis-lcz_100m dataset

GiVu

New member
Dear WRF Expert,
I'm running the model over Cyprus using three one-way nested domains at 12, 3, and 1 km, respectively. I'm considering the sf_urban_physics = 2 and the hybrid 100-m global land cover dataset with Local Climate Zones. To use this dataset, I followed the instructions provided here, which include changing the geog_data_res in namelist.wps as follows:

geog_data_res = 'cglc_modis_lcz+default', 'cglc_modis_lcz+default', 'cglc_modis_lcz+default'

I changed the GEOGRID.TBL.ARW_LCZ accordingly.
Also, I downloaded the dataset from the WPS V4 Geographical Static Data Downloads Page. Geogrid.exe, ungrib.exe, and metgrid.exe work fine. Nevertheless, when I check any of the three geo_em.d0*.nc files generated from geogrid.exe, I can't find the FRC_URB2D variable. Moreover, I tried to run some simulations, and in the wrfinput_d0*, the FRC_URB2D is there, but the values for the innermost domain are all equal to 0.
In the namelist.input, I also added:

iofields_filename = "myoutfields.txt", "myoutfields.txt", "myoutfields.txt"

In the text file, I included the following variables to be shown in the wrfout: build_height, frac_urb2d, sw_urb2d, and bw_urb2d. But, in the wrfout, I got values only for sw_urb2d and bw_urb2d. However, the LU_INDEX recognizes the correct classes from 1 to 61 of the dataset.

I've uploaded on NextCloud a folder named Hybrid_dataset containing geo_em files, the GEOGRID table, namelist.wps, namelist.input, and a screenshot of the ncview of wrfout of bw_urb2d.

Can you help me figure out what is going on?
Thanks in advance for your time and any help you could provide.
 
Hi,
Thank you for the explanation and for providing the files. Can you let me know which version of WRF you are using, and whether the version is standard "out-of-the-box" code, or if it's been modified in any way? I'm asking this because there are a few variables you either mention, or are listed in your namelist.input file that are not standard to the WRF code - for e.g., sw_urb2d, bw_urb2d, and namelist variable use_lcz_interpolation.

when I check any of the three geo_em.d0*.nc files generated from geogrid.exe, I can't find the FRC_URB2D variable
Unless you are using NLCD data (which is only available over the continental U.S.), the FRC_URB2D variable will be 0 after geogrid.


iofields_filename = "myoutfields.txt", "myoutfields.txt", "myoutfields.txt"

In the text file, I included the following variables to be shown in the wrfout: build_height, frac_urb2d, sw_urb2d, and bw_urb2d. But, in the wrfout, I got values only for sw_urb2d and bw_urb2d
In the list you gave above, "frac_urb2d" should not have an "a" in it. It should be listed as "frc_urb2d." It's possible you just misspelled it in the post, and not in the actual files, but just in case, I wanted to point that out.
 
Hi, @kwerner and @Ming Chen, thanks for your reply.
Yes, I'm using the 4.5.1 out-of-the-box version. I just realized I uploaded the wrong namelist, and apologies for the mistake. Attached you can find the correct one.
Also, I checked the myoutfields.txt file, and the misspelled name variable is only in the post. In the file, the line is the following:

+:h:0: FRC_URB2D, BUILD_HEIGHT,sw_urb2d, bw_urb2d

I'm looking for these variables to check whether the model correctly characterizes the urban areas based on the LCZ classification.

Yes, I deleted the NCLD data from the WPS_GEOG folder so that geogrid would not consider them.
 

Attachments

  • namelist.input
    6.9 KB · Views: 3
Note that the three variables in your list, i.e., BUILD_HEIGHT, sw_urb2d, bw_urb2d, are not state variables and thus they cannot be output without code modification.

I am suspicious that the WRF codes you used is not an officially released version.

Please double check.
 
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