Dear Christiane
Thanks for your comments.
> > By analogy with humidity_mixing_ratio, noting that a mass mixing
> ratio > is not quite the same thing as a mass concentration:
> > mass_mixing_ratio_of_ozone_in_air (1)
>
> Yes, but "mass_fraction_of_ozone_in_air" exists and this is the same as
> mass_mixing_ratio
It's not the same for water. Specific humidity is the ratio of mass of water to
mass of moist air, while humidity mixing ratio is the ratio of mass of water to
mass of dry air. I have been told in the past that the same distinction was
being made for other atmospheric constituents in our radiation scheme, but
looking at web definitions I agree with you that for other consituents MMR is
identical with mass fraction. Now I am puzzled which we actually use (of course
there is hardly any difference numerically) so I will check.
> > mass_fraction_of_convective_cloud_condensed_water_in_air
> Does this include ice?
Yes. condensed_water is one of the "special phrases" in the standard name
guidelines
http://cf-pcmdi.llnl.gov/documents/cf-standard-names/guidelines
and it means liquid water and ice.
Best wishes
Jonathan
Received on Thu Dec 27 2007 - 11:13:52 GMT
