[CF-metadata] approval of standard_names for aerosols and chemistry for HTAP

[Jonathan Gregory]

Dear Christiane

> but the sheer magnitude of 
> names proposed, and the possilibity that the names chosen might not be 
> the best ones, seem to frighten me a little bit...

The thought you have invested in this has resulted in a very good result, I
would say. It is good to be careful!

> If CAS numbers are neccessary, they could probably be added later in the 
> long-name attribute.

I agree.

I still have one comment on these almost-accepted names, I'm sorry to say. It's
an issue I asked about last time but I don't think we discussed:

> > The updated names are  atmosphere_emission_mass_flux_of_X, there is no
> > surface.
> 
> It sounds a bit strange to me to call it a flux when it isn't passing through
> a surface.

I wonder whether you would consider calling these tendency_of_atmosphere_
content_of_X_due_to_emission? I understand "emission" to include both emission
through the surface, and into the volume of the atmosphere.

Best wishes

Jonathan