xarray doesn't like MET output files

[blaylockbk]

I'm working through the MET tutorial and I just wanted to point out that Python's xarray package (used to read NetCDF files) does not liking MET's NetCDF output.

For instance, when loading an output file with xarray in Python

import xarray
x = xarray.open_dataset('MET_Tutorial/output/gen_vx_mask/cirlce_mask.nc')

results in this error...

MissingDimensionsError: 'lat' has more than 1-dimension and the same name as one of its dimensions ('lat', 'lon'). xarray disallows such variables because they conflict with the coordinates used to label dimensions.

The issue arises from lat and lon being both dimension names and variable names.

This is related to pydata/xarray#2233. It sounds like the xarray developers are addressing this.

A simple workaround is to drop the lat and lon variable when loading the data, but that sacrifices the grid data.

mask =  xr.open_dataset('MET_Tutorial/output/gen_vx_mask/cirlce_mask.nc', drop_variables=['lat','lon'])

I'm not sure if this issue has been brought up to the MET developers before, but given xarray's widespread use in the python community, I wanted to suggest MET change the output variable names to be latitude and longitude instead of lat and lon, or change the lat and lon dimension name to x and y.

[blaylockbk]

Resolved in xarray v2023.08.0, fixed by pydata/xarray#7989