An inquiry about the grid assignment for the physical state in the model code

[Li1108]

Hi,

I am trying to figure out how does the CESM assign grids for specific humidity. I read the model code and find these lines in physics_types.F90:

can anyone tell me what is the ulat, ulon here? How do they differ from lat, lon?

Best,
Li

 

[eaton]

The ulat and ulon arrays contain a subset of the values in the lat and lon arrays, i.e., just the unique values. For example if the columns in a chunk all have the same latitude, then ulat would just contain that one value while lat would have that value duplicated for each column.

The ulat/ulon arrays are only used in the boundarydata module which interpolates from input datasets to the model grid. They are just for efficiency in the calculations.

The grids used by CAM are determined by the dycore. They may be different for the dynamics and the physics, but all grids are set by the dycore.

 

[Li1108]

The ulat and ulon arrays contain a subset of the values in the lat and lon arrays, i.e., just the unique values. For example if the columns in a chunk all have the same latitude, then ulat would just contain that one value while lat would have that value duplicated for each column.

The ulat/ulon arrays are only used in the boundarydata module which interpolates from input datasets to the model grid. They are just for efficiency in the calculations.

The grids used by CAM are determined by the dycore. They may be different for the dynamics and the physics, but all grids are set by the dycore.

Thank you eaton!