Hello,
I am trying to use CESM2 data to initialise the WRF model. I was planning to use CMIP6 output, but was advised in this post to use the CESM2 data directly from the model.
To initialise WRF I need to interpolate to pressure levels. I was using pyngl vinth2p, which gives strange values when interpolated below surface pressure. I didn't think this would matter as these values shouldn't be used by WRF, however I am using nudging in WRF and getting very high nudging values for geopotential even high up in the atmosphere, along with very high values for 'mu' ("PERT COLUMN DRY MASS FOR FDDA GRID NUDGING").
I am not sure why the vertical interpolation below the surface is causing a problem, but I assume this is the issue. I am now trying to use geocat "interp_hybrid_to_pressure", but am unsure what the values for 'geopotential/temperature at the lowest model level' should be. Are these taken from the 3D geopotential/temperature?
Any help you can give would be much appreciated as I cannot work out what's going wrong here. I have also tried using the cmip6 output (already interpolated to pressure levels), but I get the same issue, although to a smaller degree. The result is impossibly high precipitation.
Can anyone help with this?
Many thanks,
Emily
I am trying to use CESM2 data to initialise the WRF model. I was planning to use CMIP6 output, but was advised in this post to use the CESM2 data directly from the model.
To initialise WRF I need to interpolate to pressure levels. I was using pyngl vinth2p, which gives strange values when interpolated below surface pressure. I didn't think this would matter as these values shouldn't be used by WRF, however I am using nudging in WRF and getting very high nudging values for geopotential even high up in the atmosphere, along with very high values for 'mu' ("PERT COLUMN DRY MASS FOR FDDA GRID NUDGING").
I am not sure why the vertical interpolation below the surface is causing a problem, but I assume this is the issue. I am now trying to use geocat "interp_hybrid_to_pressure", but am unsure what the values for 'geopotential/temperature at the lowest model level' should be. Are these taken from the 3D geopotential/temperature?
Any help you can give would be much appreciated as I cannot work out what's going wrong here. I have also tried using the cmip6 output (already interpolated to pressure levels), but I get the same issue, although to a smaller degree. The result is impossibly high precipitation.
Can anyone help with this?
Many thanks,
Emily