The base requirements are the XLONG and XLAT dimensions as well as the Times variable. The height_agl listed below is required for any non-surface variables.
height_agl:
'PH', 'PHB', 'HGT'
air_temperature:
'T', 'P', 'PB', 'T2'
wind:
'U', 'V', 'U10', 'V10'
relative_humidity:
'T', 'P', 'PB', 'QVAPOR', 'T2', 'PSFC', 'Q2'
dew_temperature:
'P', 'PB', 'QVAPOR', 'PSFC', 'Q2'
air_pressure:
'P', 'PRES', 'PSFC'
precipitation:
'RAINNC'
snowfall:
'SNOWNC'
surface_runoff:
'SFROFF'
gw_recharge:
'UDROFF'
downward_shortwave:
'SWDOWN'
downward_longwave:
'GLW'
ground_heat_flux:
'GRDFLX'
soil_temperature:
'TSLB', 'ZS'
soil_water:
'SMOIS', 'ZS'
pblh:
'PBLH'
albedo:
'ALBEDO'
surface_emissivity:
'EMISS'
water_vapor_mixing_ratio:
QVAPOR', 'Q2'