[CF-metadata] Standard names for cloud radiative properties

From: Pamment, JA <J.A.Pamment>
Date: Fri, 9 Nov 2007 12:28:27 -0000

Dear All,

Three new standard names have been proposed:

shortwave_cloud_radiative_effect; Wm-2
longwave_cloud_radiative_effect; Wm-2
cloud_radiative_effect; Wm-2

There has already been some email discussion of these proposals (see
below). I think the proposed names and definitions are fine. If there
are any further comments on these names please send them to the mailing
list in the usual way.

Best wishes,
Alison

> -----Original Message-----
> From: Karl Taylor [mailto:taylor13 at llnl.gov]
> Sent: 08 November 2007 17:02
> To: Pamment, JA (Alison)
> Cc: Mark Webb; Jonathan Gregory; Robert Pincus
> Subject: Re:
>
> Hi all,
>
> I think it's unanimous (I know from previous conversations that Robert
> prefers "effect").
>
> I therefore propose we define:
>
> "shortwave_cloud_radiative_effect",
> "longwave_cloud_radiative_effect"
> and for the net effect, simply "cloud_radiative_effect"
>
> We should note in the description that the cloud radiative effect is
> often referred to as "cloud radiative forcing". The longwave cloud
> radiative effect is the difference between
> toa_outgoing_longwave_flux_assuming_clear_sky and
> toa_outgoing_longwave_flux. The shortwave cloud radiative effect is
the
> difference between toa_net_downward_shortwave_flux and
> toa_net_downward_shortwave_flux_assuming_clear_sky. The cloud
radiative
> effect is the sum of the shortwave_cloud_radiative_effect and the
> longwave_cloud_radiative_effect.
>
> Alison, could you take it from here or remind me what the next step
is?
>
> thanks,
> Karl
>
>
> Pamment, JA (Alison) wrote:
> > Hi Mark and Karl,
> >
> > I see no problem in calling something cloud radiative effect in a
> > standard name and explaining in the definition that this is also
> > commonly called cloud radiative forcing. This type of thing has
already
> > been done for some names. For example, in the definition of
> > cloud_area_fraction it says 'Cloud area fraction is also called
"cloud
> > amount" and "cloud cover".'
> >
> > Cheers,
> > Alison
> >
> >> -----Original Message-----
> >> From: Mark Webb [mailto:mark.webb at metoffice.gov.uk]
> >> Sent: 08 November 2007 08:13
> >> To: Karl Taylor
> >> Cc: Pamment, JA (Alison); Jonathan Gregory; Robert Pincus; Mark
Webb
> >> Subject: Re: [CF-metadata] Re. chemicals and aerosols
> >>
> >> Hi Karl,
> >>
> >> CRE is a nice term because it is analogous to 'greenhouse effect'.
> >>
> >> However, when you use it people often query it because they are
> >> familiar with the term CRF (and of course CRF is the term used in
the
> >> vast majority of studies.)
> >>
> >> Is it possible to call these things CRE but also to note that they
> >> are often also known as CRF in the documentation?
> >>
> >> Mark
> >>
> >> On Wed, Nov 07, 2007 at 10:15:24AM -0800, Karl Taylor wrote:
> >>> Hi all,
> >>>
> >>> We need to define for the CF-conventions a standard name for
"cloud
> >>> forcing". Before proposing something to the CF discussion group,
I
> >>> would like your input. The following suggestions have been made:
> >>>
> >>> "shortwave_cloud_radiative_forcing",
> > "longwave_cloud_radiative_forcing"
> >>> and for the net forcing, simply "cloud_radiative_forcing"
> >>>
> >>> Alternatively,
> >>> "shortwave_cloud_radiative_effect",
> > "longwave_cloud_radiative_effect"
> >>> and for the net effect, simply "cloud_radiative_effect"
> >>>
> >>> Which do you think is better and why, or are there other
> > suggestions?
> >>> By convention these are (invariably?) defined as positive down and
> >>> assessed at the top of the atmosphere, though I suppose one might
> > want
> >>> to compute a surface cloud radiative effect. The nominal units
> > would be
> >>> W/m**2.
> >>>
> >>> Feel free to ask others to comment.
> >>>
> >>> Cheers,
> >>> Karl
> >>>
> >

------
Alison Pamment Tel: +44 1235 778065
NCAS/British Atmospheric Data Centre Fax: +44 1235 446314
Rutherford Appleton Laboratory Email: J.A.Pamment at rl.ac.uk
Chilton, Didcot, OX11 0QX, U.K.
Received on Fri Nov 09 2007 - 05:28:27 GMT