When working with the TVH and TVL invariant parameters from the ERA5-Land dataset, it appears that the GRIB version of the parameters is missing data below the latitude of 28deg South.
I find all of the values present in the netCDF4 version of the parameter, so this must be a GRIB file problem.
Here’s an image of the TVL data exported from the GRIB file using the tool gdaldem color-relief
And the very same output from the netCDF4 version of the TVL parameter tvl.nc
Obviously it’s translated from Long 0 to 360 instead of -180 to 180, but the data is there below Lat -28
The very same issue exists in the TVH GRIB file as well