Re: [CF-metadata] Four standard names for the AerChemMIP data request

[Martin Juckes - UKRI STFC]

Dear Alison,


I believe your interpretation of the units of 
integral_wrt_time_of_mole_stomatal_uptake_of_ozone, that they should be "mol 
m-2"  rather than  "mol m-2 s-1" as originally proposed is correct, but I've 
copied Michaela and Michael in so that they can comment. This would mean 
changing the units of pod0 [Phytotoxic ozone dose] to "mol m-2": is that 
consistent with what AerChemMIP want from this variable?


regards,

Martin





From: Pamment, Alison (STFC,RAL,RALSP)
Sent: 02 May 2018 15:20
To: Juckes, Martin (STFC,RAL,RALSP); Jonathan Gregory; cf-metadata@cgd.ucar.edu
Subject: RE: [CF-metadata] Four standard names for the AerChemMIP data request

Dear Martin and Jonathan,

Thank you for the proposal for four names for AerChemMIP and for the discussion.

1. 
tendency_of_atmosphere_mole_concentration_of_nitrous_oxide_due_to_chemical_destruction
 (mol m-3 s-1)
'The phrase "tendency_of_X" means derivative of X with respect to time. Mole 
concentration means number of moles per unit volume, also called "molarity", 
and is used in the construction "mole_concentration_of_X_in_Y", where X is a 
material constituent of Y. A chemical or biological species denoted by X may be 
described by a single term such as "nitrogen" or a phrase such as 
"nox_expressed_as_nitrogen". The chemical formula for nitrous oxide is N2O. The 
specification of a physical process by the phrase "due_to_" process means that 
the quantity named is a single term in a sum of terms which together compose 
the general quantity named by omitting the phrase. "Chemical destruction" means 
the result of all chemical reactions within the medium (here, atmosphere) that 
remove a certain amount of a particular species from the medium.'

As Martin has pointed out, this is very similar to existing names. This name is 
accepted for publication in the standard name table and will be added in the 
May update.

Martin has also drawn my attention to the fact that one of the existing 
tendency_of_atmosphere_mole_concentration names contains a stray 'of':
tendency_of_atmosphere_of_mole_concentration_of_carbon_monoxide_due_to_chemical_destruction.
 Thanks for pointing this out - I will create an alias to correct the typo:
tendency_of_atmosphere_of_mole_concentration_of_carbon_monoxide_due_to_chemical_destruction
 -> 
tendency_of_atmosphere_mole_concentration_of_carbon_monoxide_due_to_chemical_destruction.

This will also be done in the May update.

2. volume_scattering_function_in_air_due_to_ambient_aerosol_particles (m-1 sr-1)
'The volume scattering function is the intensity (flux per unit solid angle) of 
scattered radiation per unit length of scattering medium, normalised by the 
incident radiation flux. The (range of) direction(s) of scattering can be 
specified by a coordinate of scattering_angle. A coordinate variable of 
radiation_wavelength or radiation_frequency can be specified to indicate that 
the scattering applies at specific wavelengths or frequencies.The volume 
scattering function is the fraction of incident radiative flux scattered into 
unit solid angle per unit path length. The (range of) direction(s) of 
scattering can be specified by a coordinate of scattering_angle. The 
specification of a physical process by the phrase "due_to_" process means that 
the quantity named is a single term in a sum of terms which together compose 
the general quantity named by omitting the phrase. "Aerosol" means the system 
of suspended liquid or solid particles in air (except cloud droplets) and their 
carrier gas, the air itself. "Ambient_aerosol" means that the aerosol is 
measured or modelled at the ambient state of pressure, temperature and relative 
humidity that exists in its immediate environment. "Ambient aerosol particles" 
are aerosol particles that have taken up ambient water through hygroscopic 
growth. The extent of hygroscopic growth depends on the relative humidity and 
the composition of the particles. To specify the relative humidity and 
temperature at which the quantity described by the standard name applies, 
provide scalar coordinate variables with standard names of "relative_humidity" 
and "air_temperature".'

We have four existing volume scattering names:
volume_scattering_function_of_radiative_flux_in_sea_water
volume_scattering_coefficient_of_radiative_flux_in_sea_water
volume_scattering_coefficient_in_air_due_to_ambient_aerosol_particles
volume_scattering_coefficient_in_air_due_to_dried_aerosol_particles.
I notice that both the sea_water ones say 'of_radiative_flux' while neither of 
the 'air' names do. I think it does make sense to specify what is being 
scattered so I suggest we modify the current proposal to:
volume_scattering_function_of_radiative_flux_in_air_due_to_ambient_aerosol_particles
and that we also create aliases for the existing in_air names:
volume_scattering_coefficient_in_air_due_to_ambient_aerosol_particles -> 
volume_scattering_coefficient_of_radiative_flux 

Re: [CF-metadata] ISMIP6: final standard name requirement

[Martin Juckes - UKRI STFC]

Dear Alison,


thank you. I agree with the definition you give for "land ice",


regards,

Martin



From: Pamment, Alison (STFC,RAL,RALSP)
Sent: 02 May 2018 18:17
To: Juckes, Martin (STFC,RAL,RALSP); CF Metadata List
Cc: sophie.nowi...@nasa.gov
Subject: RE: ISMIP6: final standard name requirement

Dear Martin,

Thank you for proposing the new standard name land_ice_basal_temperature  
[units: K]. We already have the area_types grounded_ice_sheet and 
floating_ice_shelf, so that is  fine.

The name and units look good and I have added the following definition:
' "Land ice" means glaciers, ice-caps and ice-sheets resting on bedrock and 
also includes ice-shelves. The standard name land_ice_basal_temperature means 
the temperature of the land ice at its lower boundary.'

This name is accepted for publication in the standard name table and will be 
added in the May update.

We also have an existing name land_ice_temperature (K), currently defined only 
as '"Land ice" means glaciers, ice-caps and ice-sheets resting on bedrock and 
also includes ice-shelves.' Am I correct in thinking this is the internal 
temperature of the land ice? If so, I will add another sentence to the 
definition to make it a bit clearer.

Best wishes,
Alison

--
Alison Pamment Tel: +44 1235 778065
NCAS/Centre for Environmental Data ArchivalEmail: alison.pamm...@stfc.ac.uk
STFC Rutherford Appleton Laboratory
R25, 2.22
Harwell Oxford, Didcot, OX11 0QX, U.K.


-Original Message-
From: CF-metadata [mailto:cf-metadata-boun...@cgd.ucar.edu] On Behalf Of Martin 
Juckes - UKRI STFC
Sent: 18 April 2018 11:34
To: CF Metadata List 
Cc: sophie.nowi...@nasa.gov
Subject: [CF-metadata] ISMIP6: final standard name requirement

Hello All,


we need one more standard name for ISMIP6 to refer to the temperature at the 
base of the ice sheet. There are two MIP variables for this, one for the 
grounded section of the ice sheet and a 2nd for the floating portion. The two 
variables can use the same standard name with different area_type masks 
(grounded_ice_sheet and floating_ice_shelf respectively).


The proposed name is:

land_ice_basal_temperature  [units: K]


regards,

Martin
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[CF-metadata] PMIP (including 1 or more that originated in C4MIP) Standard Names: Carbon and Nitrogen terms

[Jonathan Gregory]

Dear Martin

Thanks for the examples. Actually all the other cases seem fine to me, but they
help to clarify why 

gross_primary_productivity_of_biomass_expressed_as_13C

seems odd to me. Every organic aerosol particle, and every molecule of a VOC,
calcite and carbon dioxide, contains carbon; every molecule of NOx and every
zooplankton (I assume) contains nitrogen. However, not every molecule of
biomass contains 13C, or even less 14C. But I appreciate that the ratios of
constituent to total are variable in the other cases as well, although never
zero, so perhaps this isn't so different. I guess it makes sense, although it
surprised me!

Best wishes

Jonathan

- Forwarded message from Martin Juckes - UKRI STFC 
 -

> Date: Wed, 25 Apr 2018 08:59:39 +
> From: Martin Juckes - UKRI STFC 
> To: Jonathan Gregory , "cf-metadata@cgd.ucar.edu"
>   
> Subject: Re: [CF-metadata] PMIP (including 1 or more that originated in
>   C4MIP) Standard Names: Carbon and Nitrogen terms
> 
> Hello Jonathan,
> 
> 
> It is definitely the mass of 13C atoms that we want, not the 13C plus oxygen 
> atoms that it was attached to prior to becoming part of the biomass.
> 
> 
> Some examples of the broader use of "A_expressed_as_B" (in which the amount 
> of A cannot generally be inferred from A):
> 
> mass_fraction_of_particulate_organic_matter_dry_aerosol_particles_expressed_as_carbon_in_air
> 
> mole_concentration_of_mesozooplankton_expressed_as_nitrogen_in_sea_water
> 
> atmosphere_moles_of_anthropogenic_nmvoc_expressed_as_carbon
> 
> mole_fraction_of_nox_expressed_as_nitrogen_in_air
> 
> 
> For comparison (where A is a molecule or ion, and B an atomic component):
> 
> sinking_mole_flux_of_calcite_expressed_as_carbon_in_sea_water
> 
> surface_downward_mass_flux_of_carbon_dioxide_expressed_as_carbon
> 
> 
> There are 270 standard names using "expressed_as", and those using it in the 
> narrow sense are, I think, a small fraction. There are a large number like 
> the nox/nitrogen example in which A refers to a collection of related 
> molecules, and many more in which A is biological organism or organic process.
> 
> 
> regards,
> 
> Martin
> 
> 
> 
> 
> From: CF-metadata  on behalf of Jonathan 
> Gregory 
> Sent: 24 April 2018 17:16
> To: cf-metadata@cgd.ucar.edu
> Subject: [CF-metadata] PMIP (including 1 or more that originated in C4MIP) 
> Standard Names: Carbon and Nitrogen terms
> 
> Dear Martin
> 
> Tricky! I'm not sure that is better. Yes, I think you've correctly described
> why I'm uncomfortable. Could you give other examples of this expanded use of
> expressed_as, for comparison?
> 
> What do we actually want to mean with these new GPP names? Is it just the mass
> of 13C atoms in the GPP? Or is it the mass of all C atoms in molecules which
> contain (at least) one 13C atom? It seems not so clear to me in "biomass" as
> in CO2, where there is only one C atom.
> 
> Best wishes
> 
> Jonathan
> 
> - Forwarded message from Martin Juckes - UKRI STFC 
>  -
> 
> > Date: Tue, 24 Apr 2018 15:21:22 +
> > From: Martin Juckes - UKRI STFC 
> > To: Jonathan Gregory 
> > CC: "cf-metadata@cgd.ucar.edu" 
> > Subject: Re: [CF-metadata] PMIP (including 1 or more that originated in
> >C4MIP) Standard Names: Carbon and Nitrogen terms
> >
> >
> > Hello Jonathan,
> >
> >
> > I think the usage of "expressed_as" has crept into new areas, while 
> > remaining consistent with the definition as given in the standard names. 
> > The current help text says "It means that the quantity indicated by the 
> > standard name is calculated solely with respect to the B contained in A, 
> > neglecting all other chemical constituents of A", what you are implying is 
> > a more restrictive interpretation with some understanding that 
> > "A_expressed_as_B" is an alternative representation of A (as 
> > surface_downward_mass_flux_of_carbon_dioxide_expressed_as_carbon would be, 
> > for most climate modellers, a simple multiple of 
> > surface_downward_mass_flux_of_carbon_dioxide [if the latter existed in the 
> > standard name table]). There are a number of terms in the standard name 
> > table for which this additional implication does not hold.
> >
> >
> > Looking at the existing names I noticed there construction "content_of", 
> > which cannot be used directly here, but might be helpful, as in 
> > "vegetation_mass_content_of_13C". For the gpp terms we can't use "content", 
> > but could perhaps replace it with "flux": 
> > gross_primary_productivity_of_biomass_mass_flux_of_13C.
> >
> >
> > This would require, I think, a change of the existing term 
> > gross_primary_productivity_of_biomass_expressed_as_carbon to 
> > 

Re: [CF-metadata] ISMIP6: final standard name requirement

[Alison Pamment - UKRI STFC]

Dear Martin,

Thank you for proposing the new standard name land_ice_basal_temperature  
[units: K]. We already have the area_types grounded_ice_sheet and 
floating_ice_shelf, so that is  fine.

The name and units look good and I have added the following definition:
' "Land ice" means glaciers, ice-caps and ice-sheets resting on bedrock and 
also includes ice-shelves. The standard name land_ice_basal_temperature means 
the temperature of the land ice at its lower boundary.'

This name is accepted for publication in the standard name table and will be 
added in the May update.

We also have an existing name land_ice_temperature (K), currently defined only 
as '"Land ice" means glaciers, ice-caps and ice-sheets resting on bedrock and 
also includes ice-shelves.' Am I correct in thinking this is the internal 
temperature of the land ice? If so, I will add another sentence to the 
definition to make it a bit clearer.

Best wishes,
Alison

--
Alison Pamment Tel: +44 1235 778065
NCAS/Centre for Environmental Data ArchivalEmail: alison.pamm...@stfc.ac.uk
STFC Rutherford Appleton Laboratory 
R25, 2.22
Harwell Oxford, Didcot, OX11 0QX, U.K.


-Original Message-
From: CF-metadata [mailto:cf-metadata-boun...@cgd.ucar.edu] On Behalf Of Martin 
Juckes - UKRI STFC
Sent: 18 April 2018 11:34
To: CF Metadata List 
Cc: sophie.nowi...@nasa.gov
Subject: [CF-metadata] ISMIP6: final standard name requirement

Hello All,


we need one more standard name for ISMIP6 to refer to the temperature at the 
base of the ice sheet. There are two MIP variables for this, one for the 
grounded section of the ice sheet and a 2nd for the floating portion. The two 
variables can use the same standard name with different area_type masks 
(grounded_ice_sheet and floating_ice_shelf respectively).


The proposed name is:

land_ice_basal_temperature  [units: K]


regards,

Martin
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[CF-metadata] Fwd: PMIP: standard names for the CMIP6 data request: tws, lighning flashes, wetland emissions, etc

[Jonathan Gregory]

Dear Martin

> (1.1) mrtws Terrestrial Water Storage [kg m-2]
> 
> land_based_water_amount
> 
> “This quantity is often known as Terrestrial Water Storage.. It includes 
> surface water (water in rivers, wetlands, lakes, snow, vegetation and 
> reservoirs) and subsurface water (soil moisture, groundwater)”

That's good, but I think that land_water_amount would be better. The phrase
"land water(s)" is sometimes used for terrestrial water storage, and it is
analogous to land_ice. However, that raises the question of whether land_ice
is specifically excluded from this quantity. I think it might be, and if so,
should it be land_liquid_water? Is permafrost also included? - if so, we will
have to be even more precise in order to include frozen water in soil and snow
but exclude glaciers and ice sheets!

> (1.2) Flashrate Lightning flash rate [km-2 s-1]
> 
> frequency_of_lightning_flash_per_unit_area

I suppose that "flashes" might sound more natural.

Best wishes

Jonathan
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[CF-metadata] VolMIP Data Request: CF Standard Names

[Jonathan Gregory]

Dear Martin

Regarding

> 2. lwsffluxaero: Longwave flux  due to volcanic aerosols at the surface [W 
> m-2]
> surface_downwelling_longwave_flux_in_air_due_to_volcanic_ambient_aerosol_particles

and the corresponding swsffluxaero, and

> 5. swtoafluxaerocs: Shortwave flux due to volcanic aerosols at TOA under 
> clear sky [W m-2]
> toa_outgoing_shortwave_flux_due_to_volcanic_ambient_aerosol_particles_assuming_clear_sky

Does these mean the difference in the relevant flux with and without the
aerosol? If so I agree that "due to" is the right phrase.

Best wishes

Jonathan
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Re: [CF-metadata] use of integral_wrt_depth_of_sea_water_practical_salinity

[Jonathan Gregory]

Dear Alison

> The question that Sebastien has raised is concerned specifically with how to 
> state the limits on the integral_wrt_Y_of_X names and I do think we can solve 
> the problem by modifying the definitions along the lines Jonathan suggests. 
> Currently the definitions all say 'The phrase "integral_wrt_X_of_Y" means int 
> Y dX. The data variable should have an axis for X specifying the limits of 
> the integral as bounds.' We could modify this to read 'The phrase 
> "integral_wrt_X_of_Y" means int Y dX. To specify the limits of the integral 
> the data variable should have an axis for X and associated coordinate bounds. 
> If no axis for X is associated with the data variable, or no coordinate 
> bounds are specified, it is assumed that the integral is calculated over the 
> entire vertical extent of the medium, e.g, if the medium is air the integral 
> is assumed to be calculated over the full depth of the atmosphere.'

Yes, I think that's a good approach. Are there really as many of these names as
you say? It's only the vertical integrals we're discussing, not the integrals
wrt time.

I agree with you in not wanting to rename the "content" quantities as
vertical integrals. I advocate only merging the names of type Z_CONTENT with
CONTENT_in_Z_layer, where the distinction is solely that the former is an
integral over the entire vertical extent of Z.

Best wishes

Jonathan

- Forwarded message from Alison Pamment - UKRI STFC 
 -

> Date: Fri, 27 Apr 2018 07:14:04 +
> From: Alison Pamment - UKRI STFC 
> To: "cf-metadata@cgd.ucar.edu" , "Sebastien
>   Villaume (sebastien.villa...@ecmwf.int)"
>   
> Subject: Re: [CF-metadata] use of
>   integral_wrt_depth_of_sea_water_practical_salinity
> 
> Dear Sebastien, All,
> 
> I have just been reading through this thread and it raises some interesting 
> points. 
> 
> When I made my original comments back in 2016 (that 
> ocean_integral_wrt_depth_of_sea_water_practical_salinity (i.e. integral over 
> the whole depth from sea floor to surface) is a special case of 
> integral_wrt_depth_of_sea_water_practical_salinity) I don't think I had fully 
> thought through how one would go about specifying the limits for the full 
> depth case.  I see now that we don't really have an agreed mechanism for 
> doing this, although a number of ideas have been put forward. I agree with 
> Martin's comment that one would expect to look at the coordinates and 
> coordinate bounds for the limits of an integral - certainly that's what we do 
> for cases where the limits define a layer and I think it's preferable  to 
> treat the full depth case similarly.
> 
> Jonathan suggested making the existing in_atmosphere_layer/in_ocean_layer 
> names aliases of the full depth atmosphere/ocean names and stating in the 
> definition that if coordinate bounds are not specified it means the entire 
> vertical extent of the atmosphere/ocean. The question that Sebastien has 
> raised is concerned specifically with how to state the limits on the 
> integral_wrt_Y_of_X names and I do think we can solve the problem by 
> modifying the definitions along the lines Jonathan suggests. Currently the 
> definitions all say 'The phrase "integral_wrt_X_of_Y" means int Y dX. The 
> data variable should have an axis for X specifying the limits of the integral 
> as bounds.' We could modify this to read 'The phrase "integral_wrt_X_of_Y" 
> means int Y dX. To specify the limits of the integral the data variable 
> should have an axis for X and associated coordinate bounds. If no axis for X 
> is associated with the data variable, or no coordinate bounds are specified, 
> it is assumed that the integral is calculated over the entire vertical extent 
> of the medium, e.g, if the medium is air the integral is assumed to be 
> calculated over the full depth of the atmosphere.'
> 
> If we take this approach then Sebastien could use the existing 
> integral_wrt_depth_of_sea_water_practical_salinity name and it would cover 
> all use cases. Do others agree? If so, then I will modify the definitions of 
> all 387 existing integral names in the next update. This will create some 
> housekeeping work for the standard name table, but it avoids the need to 
> modify the conventions which would be necessary for some of the other ideas 
> that have been discussed in this thread.
> 
> As to whether we should make layer names into aliases, e.g. 
> mass_content_of_cloud_ice_in_atmosphere_layer becoming an alias of 
> atmosphere_mass_content_of_cloud_ice, we could certainly do this by taking a 
> similar approach regarding  bounds in the definitions, but strictly speaking, 
> it's not necessary to do this to address Sebastien's question. Also, if we 
> are trying to be completely consistent about integrals and layers, it raises 
> the question of whether atmosphere_mass_content, 

[CF-metadata] Four standard names for the AerChemMIP data request

[Jonathan Gregory]

Dear Alison

> We have four existing volume scattering names:
> volume_scattering_function_of_radiative_flux_in_sea_water
> volume_scattering_coefficient_of_radiative_flux_in_sea_water
> volume_scattering_coefficient_in_air_due_to_ambient_aerosol_particles
> volume_scattering_coefficient_in_air_due_to_dried_aerosol_particles.
> I notice that both the sea_water ones say 'of_radiative_flux' while neither 
> of the 'air' names do. I think it does make sense to specify what is being 
> scattered so I suggest we modify the current proposal to:
> volume_scattering_function_of_radiative_flux_in_air_due_to_ambient_aerosol_particles
> and that we also create aliases for the existing in_air names.

Yes, I agree. Good idea.

> 3. integral_wrt_time_of_mole_stomatal_uptake_of_ozone (mol m-2 s-1)

That's good too. I agree that if it's a time-integral it should be mol m-2.
Well-spotted. I hope it's right in the CMIP6 tables.

Best wishes

Jonathan
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Re: [CF-metadata] Herbaceous vegetation area type and a new LULCC carbon flux standard name for LUMIP

[Alison Pamment - UKRI STFC]

Dear Martin,

Thank you for the proposals for one new standard name and one new area type for 
LUMIP.

1. Proposed area_type:  herbaceous_vegetation
'Herbaceous plants are plants with very flexible stems. Their leaves and stems 
die down to soil level at the end of every growing season. Herbaceous plants 
can be annual, biennial or perennial.'

This proposal has not received any comments on the list, however I think it 
looks fine so it is accepted. I will update the area_type table at the same 
time as the standard name table on 14th May.

2. Proposed standard name: 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_anthropogenic_land_use_or_land_cover_change_excluding_forestry_and_agricultural_products
 (kg m-2 s-1)
'The surface called "surface" means the lower boundary of the atmosphere. 
"Upward" indicates a vector component which is positive when directed upward 
(negative downward). In accordance with common usage in geophysical 
disciplines, "flux" implies per unit area, called "flux density" in physics. 
The phrase "expressed_as" is used in the construction A_expressed_as_B, where B 
is a chemical constituent of A. It means that the quantity indicated by the 
standard name is calculated solely with respect to the B contained in A, 
neglecting all other chemical constituents of A. The chemical formula for 
carbon dioxide is CO2. The specification of a physical process by the phrase 
"due_to_" process means that the quantity named is a single term in a sum of 
terms which together compose the general quantity named by omitting the phrase. 
"Anthropogenic" means influenced, caused, or created by human activity. 
"Anthropogenic land use change" means human changes to land, excluding forest 
regrowth. It in
 cludes fires ignited by humans for the purpose of land use change. The 
quantity with standard name 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_anthropogenic_land_use_or_land_cover_change_excluding_forestry_and_agricultural_products
 excludes the carbon dioxide flux into the atmosphere due to the processes of 
eventual disposal and decomposition of wood products such as paper, cardboard, 
furniture and timber for construction. The standard name for the quantity that 
includes product decomposition is 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_anthropogenic_land_use_or_land_cover_change.'

This proposal has not received any comments on the list. As you pointed out in 
the proposal, this one is simply an extension of the existing name 
surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_anthropogenic_land_use_or_land_cover_change
 that includes product decomposition. I have constructed the definition so as 
to explain the difference between the two.

The name, units and definition are fine so this one is accepted and will be 
included in the May standard name table update.

Best wishes,
Alison

--
Alison Pamment Tel: +44 1235 778065
NCAS/Centre for Environmental Data ArchivalEmail: alison.pamm...@stfc.ac.uk
STFC Rutherford Appleton Laboratory 
R25, 2.22
Harwell Oxford, Didcot, OX11 0QX, U.K.

-Original Message-
From: CF-metadata [mailto:cf-metadata-boun...@cgd.ucar.edu] On Behalf Of Martin 
Juckes - UKRI STFC
Sent: 18 April 2018 07:48
To: CF Metadata List 
Subject: [CF-metadata] Herbaceous vegetation area type and a new LULCC carbon 
flux standard name for LUMIP

Hello All,


We have two outstanding CF metadata requirements for the LUMIP CMIP6 data 
request.


(1) An area type is needed for non-woody, or herbaceous, vegetation.

LUMIP variable: nwdFracLut Percentage of land use tile that is non-woody 
vegetation ( e.g. herbaceous crops)


Plants can be divided into "woody" and "herbaceous" categories. The "woody" 
plants have stems which are adapted to survive harsh winters without any leaf 
cover.


Proposed area_type:  herbaceous_vegetation

Herbaceous plants are plants with very flexible stems. Their leaves and stems 
die down to soil level at the end of every growing season. Herbaceous plants 
can be annual, biennial or perennial.

(2) fLulccAtmLut carbon transferred directly to atmosphere due to any land-use 
or land-cover change activities including deforestation or agricultural fire 
[kg m-2 s-1]


The new requirement here is the identification of "direct" transfer into the 
atmosphere, which means direct from the soil and vegetation to the atmosphere, 
excluding fluxes that enter the atmosphere through a pathway which involves 
intermediary stages as forestry and agricultural products (e.g. wood harvested 
for energy generation).


There is an existing name for a flux which includes the fluxes via forestry and 
agricultural products:

"surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_anthropogenic_land_use_or_land_cover_change".

I propose extending this name to express the exclusion of the "products":

Re: [CF-metadata] Four standard names for the AerChemMIP data request

[Alison Pamment - UKRI STFC]

Dear Martin and Jonathan,

Thank you for the proposal for four names for AerChemMIP and for the discussion.

1. 
tendency_of_atmosphere_mole_concentration_of_nitrous_oxide_due_to_chemical_destruction
 (mol m-3 s-1)
'The phrase "tendency_of_X" means derivative of X with respect to time. Mole 
concentration means number of moles per unit volume, also called "molarity", 
and is used in the construction "mole_concentration_of_X_in_Y", where X is a 
material constituent of Y. A chemical or biological species denoted by X may be 
described by a single term such as "nitrogen" or a phrase such as 
"nox_expressed_as_nitrogen". The chemical formula for nitrous oxide is N2O. The 
specification of a physical process by the phrase "due_to_" process means that 
the quantity named is a single term in a sum of terms which together compose 
the general quantity named by omitting the phrase. "Chemical destruction" means 
the result of all chemical reactions within the medium (here, atmosphere) that 
remove a certain amount of a particular species from the medium.'

As Martin has pointed out, this is very similar to existing names. This name is 
accepted for publication in the standard name table and will be added in the 
May update.

Martin has also drawn my attention to the fact that one of the existing 
tendency_of_atmosphere_mole_concentration names contains a stray 'of':
tendency_of_atmosphere_of_mole_concentration_of_carbon_monoxide_due_to_chemical_destruction.
 Thanks for pointing this out - I will create an alias to correct the typo:
tendency_of_atmosphere_of_mole_concentration_of_carbon_monoxide_due_to_chemical_destruction
 -> 
tendency_of_atmosphere_mole_concentration_of_carbon_monoxide_due_to_chemical_destruction.

This will also be done in the May update.

2. volume_scattering_function_in_air_due_to_ambient_aerosol_particles (m-1 sr-1)
'The volume scattering function is the intensity (flux per unit solid angle) of 
scattered radiation per unit length of scattering medium, normalised by the 
incident radiation flux. The (range of) direction(s) of scattering can be 
specified by a coordinate of scattering_angle. A coordinate variable of 
radiation_wavelength or radiation_frequency can be specified to indicate that 
the scattering applies at specific wavelengths or frequencies.The volume 
scattering function is the fraction of incident radiative flux scattered into 
unit solid angle per unit path length. The (range of) direction(s) of 
scattering can be specified by a coordinate of scattering_angle. The 
specification of a physical process by the phrase "due_to_" process means that 
the quantity named is a single term in a sum of terms which together compose 
the general quantity named by omitting the phrase. "Aerosol" means the system 
of suspended liquid or solid particles in air (except cloud droplets) and their 
carrier gas, the air itself. "Ambient_aerosol" means that the aerosol is 
measured or modelled at the ambient state of pressure, temperature and relative 
humidity that exists in its immediate environment. "Ambient aerosol particles" 
are aerosol particles that have taken up ambient water through hygroscopic 
growth. The extent of hygroscopic growth depends on the relative humidity and 
the composition of the particles. To specify the relative humidity and 
temperature at which the quantity described by the standard name applies, 
provide scalar coordinate variables with standard names of "relative_humidity" 
and "air_temperature".'

We have four existing volume scattering names:
volume_scattering_function_of_radiative_flux_in_sea_water
volume_scattering_coefficient_of_radiative_flux_in_sea_water
volume_scattering_coefficient_in_air_due_to_ambient_aerosol_particles
volume_scattering_coefficient_in_air_due_to_dried_aerosol_particles.
I notice that both the sea_water ones say 'of_radiative_flux' while neither of 
the 'air' names do. I think it does make sense to specify what is being 
scattered so I suggest we modify the current proposal to:
volume_scattering_function_of_radiative_flux_in_air_due_to_ambient_aerosol_particles
and that we also create aliases for the existing in_air names:
volume_scattering_coefficient_in_air_due_to_ambient_aerosol_particles -> 
volume_scattering_coefficient_of_radiative_flux 
_in_air_due_to_ambient_aerosol_particles
volume_scattering_coefficient_in_air_due_to_dried_aerosol_particles -> 
volume_scattering_coefficient_of_radiative_flux_in_air_due_to_dried_aerosol_particles.
 Do you agree?

We have just one existing volume_scattering_function name, defined as 'The 
volume scattering function is the fraction of incident radiative flux scattered 
into unit solid angle per unit path length.'. Martin has suggested a different 
wording: 'The volume scattering function is the intensity (flux per unit solid 
angle) of scattered radiation per unit length of scattering medium, normalised 
by the incident radiation flux' which gives a clearer description of how the 
quantity is 

[CF-metadata] proposed new standard name for storm surge residual

[Jonathan Gregory]

Dear Andy

Thanks for your email. This is surprisingly mind-bending. Although MSL could
mean time-means on various periods, I believe that when we refer to it as a
surface in CF standard names we mean a very long-term mean, to get rid of all
variations. Of course, that's still not well-defined, because on very long
timescales other things change like climate and ocean basin bathymetry.

I don't think this is the point at issue. What I'm struggling with is whether
the elevation of the sea surface due to tide has a datum (MSL, reference
ellipsoid, geoid, etc.) or not. If, like "due to surge", it has no datum, it
means the difference between SSH with tide and without tide. What does "without
tide" mean, then? It could mean "with permanent tide but no time-varying tide",
for instance. If you include a datum you get something like "elevation of
sea surface above reference elliposid due to tide", but I'm not sure what the
attribution to tide means in that case. What's the difference between this
quantity and sea_surface_height_above_reference_ellipsoid, which is already a
standard name? The difference would seem to be the part "due to tide". But that
returns us to the question of what "without the tide" means.

Best wishes

Jonathan



- Forwarded message from "Saulter, Andrew" 
 -

> Date: Wed, 25 Apr 2018 07:08:01 +
> From: "Saulter, Andrew" 
> To: "cf-metadata@cgd.ucar.edu" 
> Subject: Re: [CF-metadata] proposed new standard name for storm surge
>   residual
> 
> Thanks Jonathon,
> 
> From the below:
> 
> We use the term "sea" - agreed. "due_to_surge" has no need for a datum 
> reference - agreed.
> 
> MSL implies no tide and no surge. I'd disagree with this; sea level at high 
> frequency will comprise contributions from lots of different components and 
> mean sea level is therefore a quantity where we have chosen to average these 
> effects out as best as possible but they haven't gone away - for example a 
> monthly mean sea level from a coastal tide gauge may still comprise some 
> tidal signal (for example an asymmetry where the equinoxes occur in different 
> months) and will certainly include variation due to a seasonal changes in the 
> surge contribution.
> 
> So from my perspective, the only difference between tide and surge is that we 
> would expect tide to always reference some form of fixed datum (which is 
> preferably more flexible than just MSL) in order to allow us to construct a 
> sea level series that is vertically referenced, whereas  surge and other 
> contributions will be relative quantities.
> 
> Cheers
> Andy
> 
> 
> 
> -Original Message-
> From: CF-metadata [mailto:cf-metadata-boun...@cgd.ucar.edu] On Behalf Of 
> Jonathan Gregory
> Sent: 24 April 2018 18:30
> To: cf-metadata@cgd.ucar.edu
> Subject: Re: [CF-metadata] proposed new standard name for storm surge residual
> 
> Dear Andy
> 
> > - I'm only going to do this for sea water levels, so from my point of 
> > view using the term "sea" is fine; I'm just aware that what comes 
> > below could be applied in other water bodies
> 
> Yes. However, we make our job simpler (as a principle in CF) by doing only 
> what we need to for the current use-cases.
> 
> > - "due_to_surge" will either a) be derived as a residual value 
> > calculated after taking a measured sea level value (referenced to some 
> > fixed datum) and subtracting a predicted tide height (referenced to 
> > same datum), or b) be a quantity that we would expect to add to a 
> > predicted tide height in order to create a total water level (again 
> > referenced to some fixed datum)
> 
> In both cases the datum is not relevant to the elevation due to surge.
> 
> > - "due_to_tide" will be the tide values mentioned above which will have to 
> > be referenced against a datum or common benchmark, e.g. chart datum, mean 
> > sea level, Ordnance Datum Newlyn, in order to make sense. 
> 
> ... whereas here the datum *is* required.
> 
> So these cases seem different after all, and may need different sorts of name 
> - at least, that's my first reaction. It's because there isn't a situation of 
> "no tide", but there is a situation of "no surge". On second thoughts, I'm 
> not sure about this distinction. No tide, I suppose, means MSL. On the other 
> hand, no surge isn't uniquely defined - something must be assumed about the 
> MSLP and the wind when there *isn't* a surge. What is that?
> 
> > So far these are variables that give us what we might term 'still water 
> > level', i.e. neglecting wave effects. However, thinking about future 
> > requirements you could easily see an extension to higher frequency 
> > parameters such as "due_to_wave_induced_setup" (minutes to hours), 
> > "due_to_run_up" (seconds to minutes), "due_to_waves" (seconds) if you were 
> > looking at a detailed approach to evaluating total water levels. All these 
> > would work like surge, 

[CF-metadata] proposed additional names for sea_surface_wave parameters

[Jonathan Gregory]

Dear Andy

Your new proposals of sections 1-3 following existing patterns, as you say,
and look fine to me.

For those of section 4, can you say precisely what "one-sided directional
width" means? The way you describe it, I wonder whether it could be described
as a processed version of the wave_direction theta. For example, if it was the
standard deviation of theta, cell_methods could describe it.

Best wishes

Jonathan

- Forwarded message from "Saulter, Andrew" 
 -

> Date: Wed, 2 May 2018 07:28:05 +
> From: "Saulter, Andrew" 
> To: "cf-metadata@cgd.ucar.edu" 
> Subject: Re: [CF-metadata] proposed additional names for sea_surface_wave
>   parameters
> 
> Adding a minor amendment to the units for the 
> 'wave_energy_at_variance_spectral_density_maximum' parameters. These should 
> be 'm2 s' rather than 'm2s' in order to be parsed by UDUNITS.
> 
> Andy
> 
> From: CF-metadata [mailto:cf-metadata-boun...@cgd.ucar.edu] On Behalf Of 
> Saulter, Andrew
> Sent: 01 May 2018 09:27
> To: cf-metadata@cgd.ucar.edu
> Subject: [CF-metadata] proposed additional names for sea_surface_wave 
> parameters
> 
> Hi all,
> 
> Please find proposals for some additional sea_surface_wave parameters, which 
> will be provided as part of Met Office operational forecast products in the 
> near future. Hopefully nothing too contentious as mostly an extension of some 
> existing CF names.
> 
> 
> 1.   Addition of 'tertiary_swell' names for existing wave parameters 
> defined under 'wind_wave', 'primary_swell' and 'secondary_swell' categories. 
> So would add:
> 
> sea_surface_tertiary_swell_wave_from_direction
> units: degree
> The quantity with standard name 
> sea_surface_tertiary_swell_wave_from_direction is the direction from which 
> the third most energetic swell waves are coming. Swell waves are waves on the 
> ocean surface and are the low frequency portion of a bimodal wave frequency 
> spectrum. The tertiary swell wave is the third most energetic swell wave. The 
> phrase "from_direction" is used in the construction X_from_direction and 
> indicates the direction from which the velocity vector of X is coming. The 
> direction is a bearing in the usual geographical sense, measured positive 
> clockwise from due north.
> 
> sea_surface_tertiary_swell_wave_mean_period
> units: s
> The quantity with standard name sea_surface_tertiary_swell_wave_mean_period 
> is the mean period of the third most energetic swell waves. Swell waves are 
> waves on the ocean surface and are the low frequency portion of a bimodal 
> wave frequency spectrum. The tertiary swell wave is the third most energetic 
> wave in the low frequency portion of a bimodal wave frequency spectrum. A 
> period is an interval of time, or the time-period of an oscillation. Wave 
> period is the interval of time between repeated features on the waveform such 
> as crests, troughs or upward passes through the mean level. Wave mean period 
> is the mean period measured over the observation duration.
> 
> sea_surface_tertiary_swell_wave_significant_height
> Swell waves are waves on the ocean surface and are the low frequency portion 
> of a bimodal wave frequency spectrum. The tertiary swell wave is the third 
> most energetic wave in the low frequency portion of a bimodal wave frequency 
> spectrum. Significant wave height is a statistic computed from wave 
> measurements and corresponds to the average height of the highest one third 
> of the waves, where the height is defined as the vertical distance from a 
> wave trough to the following wave crest.
> 
> 
> 
> 2.   Addition of peak wave period parameter to 'wind_wave', 
> 'primary_swell', 'secondary_swell' and 'tertiary_swell' categories. This 
> follows the existing standard for 
> 'sea_surface_wave_period_at_variance_spectral_density_maximum' and adds:
> 
> sea_surface_wind_wave_period_at_variance_spectral_density_maximum
> units: s
> The quantity with standard name 
> sea_surface_wind_wave_period_at_variance_spectral_density_maximum is the 
> period of the most energetic waves within the wind wave component of a sea. 
> Wind waves are waves on the ocean surface and are the high frequency portion 
> of a bimodal wave frequency spectrum. A period is an interval of time, or the 
> time-period of an oscillation. The phrase 
> "wave_period_at_variance_spectral_density_maximum", sometimes called peak 
> wave period, describes the period of the most energetic waves within a given 
> sub-domain of the wave spectrum.
> 
> sea_surface_primary_swell_wave_period_at_variance_spectral_density_maximum
> units: s
> The quantity with standard name 
> sea_surface_primary_swell_wave_period_at_variance_spectral_density_maximum is 
> the period of the most energetic waves within the primary swell wave 
> component of a sea. Swell waves are waves on the ocean surface and are the 
> low frequency portion of a bimodal wave 

Re: [CF-metadata] Standard Names to support Trac ticket 99

[Martin Juckes - UKRI STFC]

Dear Roy, Jonathan,


I understand the cause of Jonathan's concern: wikipedia suggests a broader 
interpretation of "taxon" which would be consistent with using the word to 
refer to the organisms from a biological taxon, but the Encyclopedia Britannica 
has a narrower and perhaps more scientifically precise definition in which 
"taxon" refers to the name, not the organisms matching the name 
(https://www.britannica.com/science/taxon ). The article uses the phrase 
"taxonomic category" which could be used as an alternative to Jonathan's 
suggestion:

mass_concentration_of_taxonomic_category_expressed_as_carbon_in_sea_water


regards,

Martin



From: CF-metadata  on behalf of Jonathan 
Gregory 
Sent: 01 May 2018 17:08
To: cf-metadata@cgd.ucar.edu
Subject: Re: [CF-metadata] Standard Names to support Trac ticket 99

Dear Roy

I agree that the confusion is unlikely. Maybe I shouldn't have given that
example, because it's distracting. My discomfort is just that "taxon" doesn't
mean "organisms" but "name of type of organisms" e.g. in
  mass_concentration_of_biological_taxon_expressed_as_carbon_in_sea_water
you can substitute your proposed definition of taxon, to get
  
mass_concentration_of_name_identifying_an_organism_as_belonging_to_a_unit_of_classification_expressed_as_carbon_in_sea_water
I think you mean
  
mass_concentration_of_organisms_from_biological_taxon_expressed_as_carbon_in_sea_water
That's a bit longer, but feels more comfortable to me.

Best wishes

Jonathan


- Forwarded message from "Lowry, Roy K."  -

> Date: Fri, 27 Apr 2018 11:55:26 +
> From: "Lowry, Roy K." 
> To: "cf-metadata@cgd.ucar.edu" ,
>"j.m.greg...@reading.ac.uk" 
> Subject: Re: [CF-metadata]  Standard Names to support Trac ticket 99
>
> Dear Jonathon,
>
>
> I realised that I hadn't replied to this. Think we're all agreed on 
> biological_taxon_lsid.
>
>
> I can't think of an alternative to cover your second comment, but feel that 
> 'number_concentration_of_biological_taxon' with 'concentration' and taxon in 
> the singular is clearly different from 'number_of_biological_taxa', or more 
> likely 'count_of_biological_taxa' and so feel that there is not a significant 
> risk of confusion.
>
>
> Cheers, Roy.
>
>
> Please note that I partially retired on 01/11/2015. I am now only working 7.5 
> hours a week and can only guarantee e-mail response on Wednesdays, my day in 
> the office. All vocabulary queries should be sent to enquir...@bodc.ac.uk. 
> Please also use this e-mail if your requirement is urgent.
>
>
> 
> From: CF-metadata  on behalf of Jonathan 
> Gregory 
> Sent: 16 April 2018 19:19
> To: cf-metadata@cgd.ucar.edu
> Subject: [CF-metadata] Standard Names to support Trac ticket 99
>
> Dear Roy
>
> Thanks for this. It looks sensible and well-constructed to me. I have two
> comments.
>
> * In response to your question, I think biological_taxon_lsid is better, since
> you propose that's what we use. The more generic version would be suitable if
> we offered a choice about which sort of ID to use, but it would present a
> difficulty if you wanted to provide more than one kind of ID; this would need
> more than one coord var, and it would be helpful to give them different
> standard names.
>
> * In the concentration names, I think "biological taxon" means "organisms
> of biological taxon", doesn't it? I suggest it would be better to spell this
> out in some way in the standard name. For example,
>   number_concentration_of_biological_taxon_in_sea_water
> might (surprisingly) be interpreted as meaning how many species there are
> per unit volume.
>
> Best wishes
>
> Jonathan
>
>
> - Forwarded message from "Lowry, Roy K."  -
>
> > Date: Fri, 13 Apr 2018 14:02:59 +
> > From: "Lowry, Roy K." 
> > To: "cf-metadata@cgd.ucar.edu" 
> > Subject: [CF-metadata] Standard Names to support Trac ticket 99
> >
> > Dear All,
> >
> >
> > Here is an initial batch of 8 Standard Names to support the CF taxon 
> > dimension. Two are dimension labels whilst the other six are measurements 
> > to which the taxon is a co-ordinate. Five of these are to cover Daniel's 
> > proposal that prompted the resurrection of Ticket 99.
> >
> >
> > I've presented a summary list followed by a full list with units and 
> > definitions.  I have one uncertainty in my mind (biological_taxon_label 
> > versus biological_taxon_lsid) where I would really appreciate input.
> >
> >
> > Cheers, Roy.
> >
> > biological_taxon_name
> > biological_taxon_identifier or biological_taxon_lsid – any preferences
> > number_concentration_of_biological_taxon_in_sea_water
> > 

Re: [CF-metadata] proposed additional names for sea_surface_wave parameters

[Saulter, Andrew]

Adding a minor amendment to the units for the 
'wave_energy_at_variance_spectral_density_maximum' parameters. These should be 
'm2 s' rather than 'm2s' in order to be parsed by UDUNITS.

Andy

From: CF-metadata [mailto:cf-metadata-boun...@cgd.ucar.edu] On Behalf Of 
Saulter, Andrew
Sent: 01 May 2018 09:27
To: cf-metadata@cgd.ucar.edu
Subject: [CF-metadata] proposed additional names for sea_surface_wave parameters

Hi all,

Please find proposals for some additional sea_surface_wave parameters, which 
will be provided as part of Met Office operational forecast products in the 
near future. Hopefully nothing too contentious as mostly an extension of some 
existing CF names.


1.   Addition of 'tertiary_swell' names for existing wave parameters 
defined under 'wind_wave', 'primary_swell' and 'secondary_swell' categories. So 
would add:

sea_surface_tertiary_swell_wave_from_direction
units: degree
The quantity with standard name sea_surface_tertiary_swell_wave_from_direction 
is the direction from which the third most energetic swell waves are coming. 
Swell waves are waves on the ocean surface and are the low frequency portion of 
a bimodal wave frequency spectrum. The tertiary swell wave is the third most 
energetic swell wave. The phrase "from_direction" is used in the construction 
X_from_direction and indicates the direction from which the velocity vector of 
X is coming. The direction is a bearing in the usual geographical sense, 
measured positive clockwise from due north.

sea_surface_tertiary_swell_wave_mean_period
units: s
The quantity with standard name sea_surface_tertiary_swell_wave_mean_period is 
the mean period of the third most energetic swell waves. Swell waves are waves 
on the ocean surface and are the low frequency portion of a bimodal wave 
frequency spectrum. The tertiary swell wave is the third most energetic wave in 
the low frequency portion of a bimodal wave frequency spectrum. A period is an 
interval of time, or the time-period of an oscillation. Wave period is the 
interval of time between repeated features on the waveform such as crests, 
troughs or upward passes through the mean level. Wave mean period is the mean 
period measured over the observation duration.

sea_surface_tertiary_swell_wave_significant_height
Swell waves are waves on the ocean surface and are the low frequency portion of 
a bimodal wave frequency spectrum. The tertiary swell wave is the third most 
energetic wave in the low frequency portion of a bimodal wave frequency 
spectrum. Significant wave height is a statistic computed from wave 
measurements and corresponds to the average height of the highest one third of 
the waves, where the height is defined as the vertical distance from a wave 
trough to the following wave crest.



2.   Addition of peak wave period parameter to 'wind_wave', 
'primary_swell', 'secondary_swell' and 'tertiary_swell' categories. This 
follows the existing standard for 
'sea_surface_wave_period_at_variance_spectral_density_maximum' and adds:

sea_surface_wind_wave_period_at_variance_spectral_density_maximum
units: s
The quantity with standard name 
sea_surface_wind_wave_period_at_variance_spectral_density_maximum is the period 
of the most energetic waves within the wind wave component of a sea. Wind waves 
are waves on the ocean surface and are the high frequency portion of a bimodal 
wave frequency spectrum. A period is an interval of time, or the time-period of 
an oscillation. The phrase "wave_period_at_variance_spectral_density_maximum", 
sometimes called peak wave period, describes the period of the most energetic 
waves within a given sub-domain of the wave spectrum.

sea_surface_primary_swell_wave_period_at_variance_spectral_density_maximum
units: s
The quantity with standard name 
sea_surface_primary_swell_wave_period_at_variance_spectral_density_maximum is 
the period of the most energetic waves within the primary swell wave component 
of a sea. Swell waves are waves on the ocean surface and are the low frequency 
portion of a bimodal wave frequency spectrum. The primary swell wave is the 
most energetic wave component in the low frequency portion of a bimodal wave 
frequency spectrum. A period is an interval of time, or the time-period of an 
oscillation. The phrase "wave_period_at_variance_spectral_density_maximum", 
sometimes called peak wave period, describes the period of the most energetic 
waves within a given sub-domain of the wave spectrum.

sea_surface_secondary_swell_wave_period_at_variance_spectral_density_maximum
units: s
The quantity with standard name 
sea_surface_secondary_swell_wave_period_at_variance_spectral_density_maximum is 
the period of the most energetic waves within the secondary swell wave 
component of a sea. Swell waves are waves on the ocean surface and are the low 
frequency portion of a bimodal wave frequency spectrum. The secondary swell 
wave is the most energetic wave component in the low frequency portion of a 
bimodal wave