Dear Heinke,
Please see below for a summary of the status of all the names you
proposed for ECHAM5/CLM/ERA.
The following names are fine and are accepted without modification.
>
> 'cloud_liquid_water_mixing_ratio'
> Mixing ratio of a parcel of liquid water in air is the ratio of the
> mass of liquid water to the mass of dry air.
>
> 'cloud_ice_mixing_ratio'
> Mixing ratio of a parcel of ice in air is the ratio of the mass of
ice
> to the mass of dry air.
>
> convective_precipitation_rate
>
> toa_net_downward_longwave_flux_assuming_clear_sky
>
> integral_of_surface_downwelling_longwave_flux_in_air_wrt_time Watt
> second metre**-2
>
> integral_of_surface_downwelling_shortwave_flux_in_air_wrt_time Watt
> second metre**-2
The following names are also accepted, noting that the units would
appear in the standard name table as Pa s, which is exactly equivalent
to N s m-2.
>
> integral_of_surface_downward_eastward_stress_wrt_time Newton second
> metre**-2
>
> integral_of_surface_downward_northward_stress_wrt_time Newton second
> metre**-2
> 'water_vapor_mixing_ratio'
> water vapor mixing ratio of a parcel of moist air is the ratio of the
> mass of water
> vapor to the mass of dry air.
I think there is agreement that the existing standard name
humidity_mixing_ratio has the right definition, but that
water_vapor_mixing_ratio would be more self-explanatory. Therefore I
will add the name water_vapor_mixing_ratio and make
humidity_mixing_ratio into an alias.
> 'surface_background_albedo' (This is the albedo assuming no snow but
> the
> albedo of vegetation, glacier and shelf)
Jonathan suggested using surface_albedo_assuming_no_snow and this was
agreed. This name is accepted.
>
> 'toa_outgoing_downward_shortwave_flux'
>
> 'surface_upwelling_downward_shortwave_flux_in_air'
>
> 'surface_upwelling_downward_longwave_flux_in_air'
All these quantities already exist in the standard name table without
the _downward_. Normally, 'outgoing' and 'upwelling' would indicate
that the flux is positive upwards, so I assume that by introducing the
word 'downward' you wish to have the opposite sign convention - is that
correct? We have just introduced a new standard name
minus_one_times_water_flux_into_sea_water_from_rivers to cope with the
situation where a change of sign was needed. We could do the same for
your names so that they would become:
minus_one_times_toa_outgoing_shortwave_flux
minus_one_times_surface_upwelling_shortwave_flux_in_air
minus_one_times_surface_upwelling_longwave_flux_in_air
Is this OK?
>
> In the model three different areas exist:
>
> '-where_sea/lake-ice (except shelf)'
> '-where_open_sea/lake'
> '-where_land/shelf'
>
> I need
> downward_heat_flux_in_sea_ice and lake_ice (except shelf)
>
> My proposal is a new standard name:
> downward_heat_flux_in_ice
>
> downward_heat_flux_in_ice where sea-ice and lake-ice (except shelf)
>
> I need
> ice_thickness where sea/lake-ice (except shelf)
> I think
> sea_ice_thickness where sea/lake-ice (except shelf)
> is not correct.
>
> My proposal is a new standard name:
> ice_thickness
So the actual standard names proposals are:
downward_heat_flux_in_ice; W m-2
ice_thickness; m
Now that ticket 17 has been accepted, area descriptions will appear
within the cell_methods attribute, either in a string-valued coordinate
variable with the standard name area_type, or as a string containing one
of the values permitted in a variable with standard name area_type. The
values of area_type will be standardized and the initial list, arising
from the discussion of ticket 17, is: land, sea, sea_ice, ice_free_sea,
land_ice, snow, cloud, clear_sky, vegetation, bare_ground and
all_area_types. Additions to the list of standardized area_types will
need to be proposed to the mailing list and agreed by discussion.
The discussion of the downward_heat_flux_in_ice and ice_thickness
proposals centred on how areas such as sea/lake/river should be
described and I note that there was some support for Roy's suggestion of
water_body.
For the purpose of these particular proposals we need a description for
"sea-ice and lake-ice (except shelf)". It seems to me that the problem
here is with the "except shelf". If we were talking about all ice
floating on a water body I would suggest that we could use "where
ice_covered_water_body" or "where water_body_ice" (the latter is by
analogy with "sea_ice" although I think it's less clear). So, for
example, we would have: ice_thickness where ice_covered_water_body.
Please correct me if I am wrong but my understanding of shelf ice is
that it forms over land and then flows out to sea due to the action of
gravity. By contrast, sea-ice and lake-ice are formed by freezing at
the surface of the water body and as a result are much thinner than
shelf ice. Looked at in this way, I suggest that what we need is a
description of the type of ice as well as a description of the ice
location. We need something like:
downward_heat_flux_in_ice_formed_by_freezing_of_water_body where
ice_covered_water_body
thickness_of_ice_formed_by_freezing_of_water_body where
ice_covered_water_body
Do you agree? (I'm afraid I can't think of a more concise phrase for
"formed_by_freezing_of_water_body"!)
Best wishes,
Alison
------
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.
--
Scanned by iCritical for STFC.
Received on Wed Oct 22 2008 - 23:20:20 BST
