[CF-metadata] one new standard name

From: Jonathan Gregory <j.m.gregory>
Date: Fri, 24 Feb 2006 13:34:12 +0000

Dear Burkhardt

> we need this parameter for atmospheric water budget studies where it
> balances amongst others with the precipitation amount (given in kg m-2).
> Therefore I am not sure if (kg m-2 s-1) is appropriate??

I see. This is related to Elke's request for change_in_X, I think; I might
have been wrong to disagree with that proposal. You could do it with rates,
couldn't you i.e. tendency_of_atmosphere_water_content and precipitation_flux
are both in kg m-2 s-1 and could appear in the same budget ("tendency" means
d/dt). But you want to use quantities which are extensive in time rather
than intensive i.e. a change over a certain interval, rather than the average
rate over that interval. In that case you want precipitation_amount and
change in atmosphere water content, both in kg m-2, defining "change" to mean
the difference in a quantity going from one time to another. I was concerned
that we might have to add "change_in" to many quantities, potentially, in which
case it might be better handled in another way. But perhaps it is not any more
of a problem than tendency_in - so far there are not many of those. If it was
seen as the time-integral of a tendency, this is quite a restrictive idea. We
would not, for example, use "change in" to mean the difference of a quantity
between two climates.

Any comments?

Best wishes

Jonathan
Received on Fri Feb 24 2006 - 06:34:12 GMT