IFS Forecast 3D field data

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Joined: Fri Oct 12, 2018 6:38 am
Location: Gdansk University of Technology

IFS Forecast 3D field data

Post by figurski » Thu Apr 22, 2021 10:23 pm


I am starting to work in the WRF model with initial data from the IFS model. I have the following field in the 3D files (model level):
Specific cloud ice water content
Specific cloud liquid water content
Specific snow water content
Specific rain water content

I know that the WRF model reads fields, among other things

Rain Water mixing ratio
Snow Water mixing ratio
Ich Water mixing ratio

Is there any method to replace the fields, e.g. field "Specific rain water content" with field "Rain Water mixing ratio" so that ungrib and metgrib read them correctly. And of course the other fields I have mentioned above.

I will be grateful for any help.

Ming Chen
Posts: 1456
Joined: Mon Apr 23, 2018 9:42 pm

Re: IFS Forecast 3D field data

Post by Ming Chen » Fri Apr 30, 2021 6:00 pm

All variables ungrib extracts from the forcing data are determined by Vtable. If you want to extract other variables from IFS, you need to modify Vtable to provide correct GRIB2 parameters for those variables.
Then you need to modify metgrid.tbl so that mtgrid.exe can read ad process these new variables. For details, please see the document:
https://www2.mmm.ucar.edu/wrf/users/tut ... vanced.pdf
WRF USEr's guide also describes issues related to Vtable and metgrid.tbl.
Hope these information is helpful for you.
WRF Help Desk

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