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real.exe SIZE MISMATCH num_metgrid_levels

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GDAS data was used to run WRF v3, but the real.exe report this error:

metgrid input_wrf.F first_date_input = 2016-12-21_12:00:00
metgrid input_wrf.F first_date_nml = 2016-12-21_12:00:00
-------------- FATAL CALLED ---------------
input_wrf.F: SIZE MISMATCH: namelist ide,jde,num_metgrid_levels= 191
131 32 ; input data ide,jde,num_metgrid_levels= 191
131 34
In some cases, this would mean that the num_metgrid_levels in the namelist.input and the met_em file are not the same, but, when I use
ncdump -h met_em.d01.2016-12-21_12:00:00| grep BOTTOM-TOP_GRID_DIMENSION, I got
and ncdump -h met_em.d01.2016-12-21_12:00:00| grep num_metgrid_levels, it was 34. In the namelist.input, num_metgrid_levels was set to 32.

In short, real.exe read a 32 level met_em input file and report it has 34 levels as the BOTTOM-TOP_GRID_DIMENSION in the met_file are not the same as num_metgrid_levels.
how to solve this problem?
Would you please check all your met_em files using the command:
ncdump -h met_em.d01.yyyy-mm-dd_hh:00:00| grep num_metgrid_levels

This is just to make sure that all your met_em files have the same num_metgrid_levels

It looks like this number is different in different met_em files.
Note that the value of num_metgrid_levels in your met-em files is the value you should specify in namelistt.input.

It is required that all met_em files have the same value of num_metgrid_levels.
Thanks for your reply!
The problem is for the same met_em file, the num_metgrid_levels and BOTTOM-TOP_GRID_DIMENSION are not the same, num_metgrid_levels is 32 while the BOTTOM-TOP_GRID_DIMENSION is 34. I use the following code to check all the met_em files, please see the attachment for the result.
ncdump -h met_em.d01.yyyy-mm-dd_hh:00:00| grep num_metgrid_levels
ncdump -h met_em.d01.yyyy-mm-dd_hh:00:00| grep BOTTOM-TOP_GRID_DIMENSION
real.exe read the BOTTOM-TOP_GRID_DIMENSION to determine the vertical levels, and the num_metgrid_levels in the namelist.input was set to 32, as it was 32 for GDAS data in those times. Then the error occured.


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  • num_metgrid_levels.txt
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