Issue with Limited Area Single Precision

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weathertom

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I've been able to get a limited area mesh to work successfully with the default (double precision) configuration. However, when I recompiled in single precision and ran the double_to_float_grid program to convert the SCVT grid to a single precision grid it no longer worked. The log file indicated that the bdyMaskCell was zero and therefore would not work with the lbc function enabled. I did an ncdump on the grid.nc file, and it did not contain a bdyMaskCell variable (I did an ncdump on the original double precision grid.nc file and it included bdyMaskCell). I'm guessing (perhaps) double_to_float_grid may need to be updated to account for the limted area functionality?
 
It's actually not necessary to run the double_to_float_grid conversion tool anymore -- MPAS can now natively read double-precision input files. I've been slowly trying to remove references to the double_to_float_grid tool.

Could you give the model a try using the double-precision regional mesh file created by MPAS-Limited-Area? That should work, but in case it doesn't, I'll be glad to assist!
 
I apologize if my post was confusing. I am able to successfully run a limited area simulation with double precision. I want to run single precision, but received the error mentioned above when I tried to do so. I will retry with the original double precision grid file while running in single precision mode.

mgduda said:
It's actually not necessary to run the double_to_float_grid conversion tool anymore -- MPAS can now natively read double-precision input files. I've been slowly trying to remove references to the double_to_float_grid tool.

Could you give the model a try using the double-precision regional mesh file created by MPAS-Limited-Area? That should work, but in case it doesn't, I'll be glad to assist!
Click to expand...
 
It may be necessary to add
Code: 
precision="double"
to the definition of the "input" stream in the streams.init_atmosphere or streams.atmosphere files. For more details, you can consult section 5.2 of the User's Guide.
 
Thank you, this worked and allowed me to execute a limited area run in single precision with the GFS IC/BC.

mgduda said:
It may be necessary to add
Code: 
precision="double"
to the definition of the "input" stream in the streams.init_atmosphere or streams.atmosphere files. For more details, you can consult section 5.2 of the User's Guide.
Click to expand...
 
Thanks for the update -- it's good to know that you're able to run in single-precision with GFS ICs/LBCs. I'll modify the users guide to remove references to the "double_to_float_grid" utility since it's no longer needed, and since using the "grid_rotate" utility on high-resolution, variable-resolution meshes is known to be problematic (there are no issues with double-precision meshes).
 
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