Or to compare with precipitation, evaporation, and other variables, how to convert to mm/day?
It is possible?
Thank you!
Conversion from kg/kg to g/kg is as simple as multiplying by 1000.
Or to compare with precipitation, evaporation, and other variables, how to convert to mm/day?
I would say that this conversion is not possible because the units are not "equivalent". Relative humidity is a description of the content of moisture in the air whereas mm/day
is a rate, which has a temporal component.
Consider using the UDUNITS package, which has various implementations in python and R: