[CF-metadata] Final 17 terms for CMIP6 LS3MIP.

From: Jonathan Gregory <j.m.gregory>
Date: Mon, 11 Jun 2018 14:28:15 +0100

Dear Alison and Martin

Here are comments I sent last week - maybe they've been covered by others
since then.

Best wishes

Jonathan

----- Forwarded message from Jonathan Gregory <j.m.gregory at reading.ac.uk-----

Date: Tue, 5 Jun 2018 18:05:07 +0100
From: Jonathan Gregory <j.m.gregory at reading.ac.uk>
To: cf-metadata at cgd.ucar.edu
Subject: [CF-metadata] Final 17 terms for CMIP6 LS3MIP.

Dear Martin

> 1.2 albsn Snow and Ice Albedo [1]
> Albedo of snow and ice covered surface.
> snow_and_ice_albedo
> Snow and ice albedo.
> -- OR --
> This could be handled with existing name surface_albedo and a new area type "snow_or_ice". [Note that "landice" appears to exclude ice on lakes, which may be a significant component of this albedo]

The latter would seem preferable and more general if it's what is needed. Does
this snow-and-ice area include the canopy, if it's got snow on it?

> water_evaporation_flux_from_canopy_due_to_intersection
                                            interception

> 2.2 eow Open Water Evaporation [kg m-2 s-1]
>
> A new term "water_evaporation_flux_from_open_water" would work here, but it might make more sense to define an area type for open water and use the existing standard name "water_evaporation_flux".

I think that depends on whether it means the evaporation from an area which
happens to be open water, or is it the water evaporation flux assuming open
water? What is open water? Does it mean the area_type ice_free_sea?

> 2.3 et Total Evapotranspiration [kg m-2 s-1]
> ?Evapotranspiration? is a new concept to the CF standard names, but appears to be clearly defined.
> evapotranspiration_flux
> ?Evapotranspiration refers to the flux of water into the atmosphere from a combination of transpiration by plants and evaporation from soil and other land surfaces.?

I think we must be careful about this. I believe that "evaporation" from
vegetated land surface has always been interpreted to mean "evapotranspiration"
since we have never been asked for that word before. We have names
for soil evaporation, canopy evaporation and transpiration, and I think those
three add up to evapotranspiration over land, so we don't need a new name.

> 4. Nudging increments [2]
nudging_increment_in_ for this special sort of change is a good idea. Thanks.

> 5. River in- and out-flow [2]
> river_water_volume_transport_into_cell
> river_water_volume_transport_out_of_cell

Using the word "cell" makes it model-specific, but I suppose these terms could
be more general; you might be monitoring the inflow and outflow of a lake, for
example. Would it be OK to use the words the MIP proposed, from_upstream and
to_downstream?

Your proposals for all the others look good to me.

Best wishes

Jonathan

----- End forwarded message -----
Received on Mon Jun 11 2018 - 07:28:15 BST