That's a really comprehensive first go Alison - thank you so much. Here are my
responses, with yellow highlighting anything I've typed, and strike-through
anything I removed. Email is not the best at track-changes, so I hope these are
clear.
Regards,
Chris
General note: as far as possible all carbon pools and most fluxes have been
given a nitrogen equivalent. So nVeg parallels cVeg for example, and the
sub-components nVeg=nStem+nLeaf+nRoot+nOther parallel the carbon equivalents.
The overriding request if a model doesn't map neatly to these is that all
carbon and nitrogen is reported somewhere so that subsequent analysis tracks
conservation.
1-3 are sub components of nLitter: nLitter = nLitterCwd + nLitterSurf +
nLitterSubSurf
(nLitterCwd)
1. wood_debris_mass_content_of_nitrogen (kg m-2) ' "Content" indicates a
quantity per unit area. "Wood debris" means dead organic matter composed of
coarse wood. It is distinct from fine litter. Definition of "fine" and "coarse"
litter are up to each model group, but as for the parallel carbon pools the sum
should agree with the total nLitter.'
(nLitterSurf)
2. surface_litter_mass_content_of_nitrogen (kg m-2) ' "Content" indicates a
quantity per unit area. "Litter" is dead plant material in or above the soil.
"Surface litter" means the part of fine litter resting above the soil surface.'
(nLitterSubSurf)
3. subsurface_litter_mass_content_of_nitrogen (kg m-2) ' "Content" indicates a
quantity per unit area. "Litter" is dead plant material in or above the soil.
"Subsurface litter" means the part of fine litter mixed within the soil below
the surface.'
4-7 are sub-components of nVeg
(nStem)
4. wood_biomass_content_of_nitrogen (kg m-2) ' "Content" indicates a quantity
per unit area.'
This is by analogy with the existing standard name 'wood_carbon_content'.
Although we don't currently define 'wood' in this context I am sure it means
'living wood' as opposed to wood_debris. The CMIP6 data request talks about
'stem'. I appreciate that 'stem' could refer to more than just trees, whose
stems are living wood', but I think these names are essentially trying to
describe the same thing. For this name we could perhaps even say
living_wood_mass_content_of_nitrogen (and make an alias for the carbon name so
that it follows the same pattern). What do you think?
Yes, we mean living biomass and not dead wood (covered in nLitterCwd above).
Hence we prefer Stem to Wood for this reason (as per carbon pool too).
(nLeaf)
5. leaf_mass_content_of_nitrogen (kg m-2) ' "Content" indicates a quantity per
unit area.'
OK
(nRoot)
6. root_mass_content_of_nitrogen (kg m-2) ' "Content" indicates a quantity per
unit area.'
OK
(nOther)
7. miscellaneous_living_matter_mass_content_of_nitrogen (kg m-2) ' "Content"
indicates a quantity per unit area. "Miscellaneous living matter" means all
those parts of living vegetation that are not leaf, wood or root or other
separately named components.'
This is by analogy with the existing name
miscellaneous_living_matter_carbon_content.
There are no other separately named pools, so nStem+nLeaf+nRoot+nOther should
identically equal the total in nVeg (and parallel for carbon pools and cVeg)
(fNVegSoil)
8. nitrogen_mass_flux_into_soil_from_vegetation_excluding_litter (kg m-2 s-1)
'In accordance with common usage in geophysical disciplines, "flux" implies per
unit area, called "flux density" in physics. "Vegetation" means any living
plants e.g. trees, shrubs, grass. "Litter" is dead plant material in or above
the soil.'
By analogy with the existing name
carbon_mass_flux_into_soil_from_vegetation_excluding_litter.
OK
(fNVegLitter)
9. nitrogen_mass_flux_into_litter_from_vegetation (kg m-2 s-1) 'In accordance
with common usage in geophysical disciplines, "flux" implies per unit area,
called "flux density" in physics. "Litter" is dead plant material in or above
the soil. "Vegetation" means any living plants e.g. trees, shrubs, grass.
OK
(fNLitterSoil)
10. nitrogen_mass_flux_into_soil_from_litter (kg m-2 s-1) 'In accordance with
common usage in geophysical disciplines, "flux" implies per unit area, called
"flux density" in physics. "Litter" is dead plant material in or above the
soil.'
OK
(fBNF)
11.
tendency_of_terrestrial_mass_content_of_inorganic_nitrogen_expressed_as_nitrogen_due_to_fixation
(kg m-2 s-1) 'The phrase "tendency_of_X" means derivative of X with respect to
time. "Content" indicates a quantity per unit area. The "soil content" of a
quantity refers to the vertical integral from the surface down to the bottom of
the soil model. For the content between specified levels in the soil, standard
names including "content_of_soil_layer" are used. 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. "Inorganic nitrogen" describes a family of chemical species
which, in soil, usually consists of nitrate and ammonium compounds which act as
nitrogen nutrients. 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.
"Nitrogen fixation" means the production of ammonia from nitrogen gas.
Organisms that fix nitrogen are termed "diazotrophs".'
Was I right to call this one 'inorganic_nitrogen'? I borrowed the last two
sentences of the definition from an ocean name. Do they accurately describe
land based nitrogen fixation? My understanding is that 'diazotrophs' is a
general term and not confined to ocean organisms but I'd be pleased if someone
could confirm that!
I suggest we:
- Say "terrestrial" instead of "soil" because this term is mainly about
plants fixing nitrogen directly from N2 in the atmosphere. Some models may have
it as a term going into the vegetation, some into the soil. We need to capture
either/both, so it's not just the tendency of the soil nitrogen.
- Don't specify organic/inorganic. If the fixed N goes into the
vegetation it will not be in inorganic form, so again we need to leave this
open to cover any form of uptake.
- Don't mention anything about ammonia or diazotrophs - the terrestrial
uptake doesn't go via ammonia, and I'm not sure the exact name of the organisms
that do it are relevant.
(fNLandToOcean)
12. mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_into_sea_from_rivers
(kg m-2 s-1) '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. "Nitrogen compounds" summarizes all chemical
species containing nitrogen atoms. The list of individual species that are
included in this quantity can vary between models. Where possible, the data
variable should be accompanied by a complete description of the species
represented, for example, by using a comment attribute.'
OK
Are the nitrogen species and its definition the right ones?
We just want to track the amount of nitrogen - so the species don't matter as
long as all nitrogen is reported. I don't think we need to list any
specifically in the variable definition.
(fNOx)
13.
mass_flux_of_nox_expressed_as_nitrogen_out_of_vegetation_and_litter_and_soil
(kg m-2 s-1) '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. "Nox" means a combination of two radical
species containing nitrogen and oxygen NO+NO2. "Vegetation" means any living
plants e.g. trees, shrubs, grass. "Litter" is dead plant material in or above
the soil.'
OK
(fNloss)
14.
mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_out_of_vegetation_and_litter_and_soil
(kg m-2 s-1) '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. "Nitrogen compounds" summarizes all chemical
species containing nitrogen atoms. The list of individual species that are
included in this quantity can vary between models. Where possible, the data
variable should be accompanied by a complete description of the species
represented, for example, by using a comment attribute. "Vegetation" means any
living plants e.g. trees, shrubs, grass. "Litter" is dead plant material in or
above the soil.'
OK - but this should exclude anything to do with land-use/cover change as these
are covered below in fAnthDisturb/fNProduct
Are the nitrogen species and its definition the right ones?
We just want to track the amount of nitrogen - so the species don't matter as
long as all nitrogen is reported. I don't think we need to list any
specifically in the variable definition.
(fNdep)
Is this really a new variable? I'm surprised the chemistry community don't
already have nitrogen deposition?
15.
tendency_of_atmosphere_mass_content_of_reactive_nitrogen_expressed_as_nitrogen_due_to_deposition
(kg m-2 s-1) 'The phrase "tendency_of_X" means derivative of X with respect to
time. "Content" indicates a quantity per unit area. The "atmosphere content" of
a quantity refers to the vertical integral from the surface to the top of the
atmosphere. For the content between specified levels in the atmosphere,
standard names including "content_of_atmosphere_layer" are used. 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 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. "Deposition" is the sum of wet and dry deposition.'
Sounds OK, but our intended sign convention is a positive flux into vegetation,
so this could be tendency of terrestrial nitrogen? Rather than tendency of the
atmosphere
We don't currently have any definition for 'reactive_nitrogen'. Please could
you provide one?
Basically, anything that's not N2 gas
(fNfert)
16.
tendency_of_soil_mass_content_of_inorganic_nitrogen_expressed_as_nitrogen_due_to_fertilization
(kg m-2 s-1) 'The phrase "tendency_of_X" means derivative of X with respect to
time. "Content" indicates a quantity per unit area. The "soil content" of a
quantity refers to the vertical integral from the surface down to the bottom of
the soil model. For the content between specified levels in the soil, standard
names including "content_of_soil_layer" are used. 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. "Inorganic nitrogen" describes a family of chemical species
which, in soil, usually consists of nitrate and ammonium compounds which act as
nitrogen nutrients. "Fertilization" means the addition of artificial
fertilizers and animal manure to soil for the purpose of increasing plant
nutrient concentrations, and could by model choice be either into nSoil or
nMineral pools.'
Is it right to say 'inorganic_nitrogen' for this one? Is the definition of
'fertilization' okay?
Yes - definition of fertilisation is OK.
No - it doesn't have to be inorganic. Again this might differ by model, and we
just want to capture how much N is going into the system. I've suggested we
should also be specific that it includes either organic or inorganic pool in
case the term "tendency of soil mass content of nitrogen" is taken to refer to
nSoil and not nMineral.
(fNgasFire)
17.
surface_upward_mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_due_to_emission_from_fires
(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.
"Nitrogen compounds" summarizes all chemical species containing nitrogen atoms.
Usually, particle bound and gaseous nitrogen compounds, such as atomic nitrogen
(N), nitrogen monoxide (NO), nitrogen dioxide (NO2), dinitrogen pentoxide
(N2O5), nitric acid (HNO3), nitrate (NO3-), peroxynitric acid (HNO4), ammonia
(NH3), ammonium (NH4+), bromine nitrate (BrONO2), chlorine nitrate (ClONO2) and
organic nitrates (most notably p eroxyacetyl nitrate, sometimes referred to as
PAN, (CH3COO2NO2)) are included. The list of individual species that are
included in this quantity can vary between models. Where possible, the data
variable should be accompanied by a complete description of the species
represented, for example, by using a comment attribute. 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. "Emission" means emission from a primary source
located anywhere within the atmosphere, including at the lower boundary (i.e.
the surface of the earth). "Emission" is a process entirely distinct from
"re-emission" which is used in some standard names. The term "fires" means all
biomass fires, whether naturally occurring or ignited by humans.'
Are the nitrogen species and its definition the right ones?
We just want to track the amount of nitrogen - so the species don't matter as
long as all nitrogen is reported. I don't think we need to list any
specifically in the variable definition.
(fNgasNonFire)
18.
surface_upward_mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_due_to_all_land_processes_excluding_fires
(kg m-2 s-1) ' "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.
"Nitrogen compounds" summarizes all chemical species containing nitrogen atoms.
Usually, particle bound and gaseous nitrogen compounds, such as atomic nitrogen
(N), nitrogen monoxide (NO), nitrogen dioxide (NO2), dinitrogen pentoxide
(N2O5), nitric acid (HNO3), nitrate (NO3-), peroxynitric acid (HNO4), ammonia
(NH3), ammonium (NH4+), bromine nitrate (BrONO2), chlorine nitrate (ClONO2) and
organic nitrates (most notably peroxyacetyl nitrate, sometimes referred to as
PAN, (CH3COO2NO2)) are inc luded. The list of individual species that are
included in this quantity can vary between models. Where possible, the data
variable should be accompanied by a complete description of the species
represented, for example, by using a comment attribute. 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. "All land processes" means plant and soil
respiration, photosynthesis, animal grazing, crop harvesting, natural fires and
anthropogenic land use change.'
We just want to track the amount of nitrogen - so the species don't matter as
long as all nitrogen is reported. I don't think we need to list any
specifically in the variable definition.
This one is by analogy with the existing names
surface_net_downward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_all_land_processes
and
surface_net_downward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_all_land_processes_excluding_anthropogenic_land_use_change.
Are the nitrogen species and its definition the right ones?
(fNAnthDisturb)
19.
tendency_of_atmosphere_mass_content_of_nitrogen_compounds_expressed_as_nitrogen_due_to_anthropogenic_land_use_or_land_cover_change
(kg m-2 s-1) 'The phrase "tendency_of_X" means derivative of X with respect to
time. "Content" indicates a quantity per unit area. The "atmosphere content" of
a quantity refers to the vertical integral from the surface to the top of the
atmosphere. For the content between specified levels in the atmosphere,
standard names including "content_of_atmosphere_layer" are used. 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 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. "Nitrogen compounds" summarizes all chemical species containing
nitrogen atoms. Usually, particle bound and gaseous nitrogen compounds, such as
atomic nitrogen (N), nitrogen monoxide (NO), nitrogen dioxide (NO2), dinitrogen
pentoxide (N2O5), nitric acid (HNO3), nitrate (NO3-), peroxynitric acid (HNO4),
ammonia (NH3), ammonium (NH4+), bromine nitrate (BrONO2), chlorine nitrate
(ClONO2) and organic nitrates (most notably peroxyacetyl nitrate, sometimes
referred to as PAN, (CH3COO2NO2)) are included. The list of individual species
that are included in this quantity can vary between models. Where possible, the
data variable should be accompanied by a complete description of the species
represented, for example, by using a comment attribute. 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 includes fires ignited b y humans for
the purpose of land use change and the processes of eventual disposal and
decomposition of wood products such as paper, cardboard, furniture and timber
for construction.'
OK
Are the nitrogen species and its definition the right ones?
We just want to track the amount of nitrogen - so the species don't matter as
long as all nitrogen is reported. I don't think we need to list any
specifically in the variable definition.
(fNProduct)
20.
nitrogen_mass_flux_into_forestry_and_agricultural_products_due_to_anthropogenic_land_use_or_land_cover_change
(kg m-2 s-1) 'In accordance with common usage in geophysical disciplines,
"flux" implies per unit area, called "flux density" in physics. Examples of
"forestry and agricultural products" are paper, cardboard, furniture, timber
for construction, biofuels and food for both humans and livestock. Models that
simulate land use changes have one or more pools of nitrogen that represent
these products in order to conserve nitrogen and allow its eventual release
into the atmosphere, for example, when the products decompose in landfill
sites. "Anthropogenic" means influenced, caused, or created by human activity.
"Anthropogenic land use change" means human changes to land, excluding forest
regrowth. It includes fires ignited by humans for the purpose of land use
change and the processes of eventual disposal and decomposition of wood
products such as paper, cardboard, furniture and timber for construction.'
OK
21-23, combines with raOther to sum to give total autotrophic respiration:
ra = raStem + raLeaf + raRoot + raOther
(raStem)
21. surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_wood (kg m-2
s-1) ' "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 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. Plant respiration is
the sum of respiration by parts of plants both above and below the soil. Plants
which photosynthesise are autotrophs i.e. "producers" of the biomass which they
respire from inorganic precursors using sunlight for energy.'
OK
As for proposal (4), 'wood' means living wood. (We should adopt consistent
terminology for both). There are existing names for plant respiration -
'plants' is currently the term used in standard names for 'autotrophs'.
(raLeaf)
22. surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_leaves (kg
m-2 s-1) ' "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 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. Plant
respiration is the sum of respiration by parts of plants both above and below
the soil. Plants which photosynthesise are autotrophs i.e. "producers" of the
biomass which they respire from inorganic precursors using sunlight for energy.'
OK
(raRoot)
23. surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_roots (kg
m-2 s-1) ' "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 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. Plant
respiration is the sum of respiration by parts of plants both above and below
the soil. Plants which photosynthesise are autotrophs i.e. "producers" of the
biomass which they respire from inorganic precursors using sunlight for energy.'
OK
24, combine with other npp components to sum to give total npp:
npp = nppStem + nppLeaf + nppRoot + nppOther
(nppOther)
24.
net_primary_productivity_of_biomassvegetation_expressed_as_carbon_accumulated_in_miscellaneous_living_matter
(kg m-2 s-1) ' "Miscellaneous living matter" means all those parts of living
vegetation that are not leaf, wood, root or other separately named components.
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. "Production of carbon" means
the production of biomass expressed as the mass of carbon which it contains.
Net primary production is the excess of gross primary production (rate of
synthesis of biomass from inorganic precursors) by autotrophs ("producers"),
for example, photosynthesis in plants or phytoplankton, over the rate at which
the autotrophs themselves respire some of this biomass. "Productivity" means
production per unit area.'
OK - but suggest "of vegetation" rather than "of biomass"
25, 26 are sub-components of rh, and sum to give the total:
rh = rhLitter + rhSoil
(rhLitter)
25.
surface_upward_mass_flux_of_carbon_due_to_heterotrophic_respiration_in_litter
(kg m-2 s-1) ' "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 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. "Litter" is
dead plant material in or above the soil. Heterotrophic respiration is
respiration by heterotrophs ("consumers"), which are organisms (including
animals and decomposers) that consume other organisms or dead organic material,
rather than synthesising organic material from inorganic precursors using
energy from the environment (especially sunlight) as autotrophs ("producers")
do. Heterotrophic respiration goes on both above and within the soil and litter
pools.'
OK
We have one existing name for 'heterotrophic_respiration'.
Yes - these are sub-components of it
(rhSoil)
26. surface_upward_mass_flux_of_carbon_due_to_heterotrophic_respiration_in_soil
(kg m-2 s-1) ' "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 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.
Heterotrophic respiration is respiration by heterotrophs ("consumers"), which
are organisms (including animals and decomposers) that consume other organisms
or dead organic material, rather than synthesising organic material from
inorganic precursors using energy from the environment (especially sunlight) as
autotrophs ("producers") do. Heterotrophic respiration goes on both above and
within the soil and litter pools.'
OK
(tSoilPools)
27. soil_pool_carbon_decay_rate (kg m-2 s-1) ' "Soil carbon" is the organic
matter present in soil quantified by the mass of carbon it contains. Soil
carbon is returned to the atmosphere as the organic matter decays. The decay
process takes varying amounts of time depending on the composition of the
organic matter, the temperature and the availability of moisture. A carbon
"soil pool" means the carbon contained in organic matter which has a
characteristic period over which it decays and releases carbon into the
atmosphere.'
This is a new quantity, although we do have some existing names that refer to
soil_pools. I guessed the unit from the quantity - is it correct?
This quantity is meant to complement the respiration one and give the turnover
rate, hence units simply "per second, s-1". Each modelled soil carbon pool will
have a characteristic turnover time, which is then modified by environmental
conditions such as temperature and moisture so that the turnover time varies in
space and time. Hence it is requested as a new variable. We request here the
turnover RATE rather than TIME, defined as 1/(turnover time). Use the same
pools reported under cSoilPools.
(co23D)
28. mass|mole_concentration_of_carbon_dioxide_passive_tracer_in_air
What are the units of this quantity? Knowing the unit will allow us to decide
if this should be a mass or a mole concentration (or something else). I wasn't
really sure of the purpose of this name - by using carbon dioxide as a tracer I
assume that means it is conserved by being treated as chemically inert. Can you
give me some more details about this one please?
This is requested to be a mass mixing ratio in kg CO2 / kg dry air. Report 3D
field of model simulated atmospheric CO2 mass mixing ration on model levels.
--
Dr Chris Jones
Head, Earth System and Mitigation Science Team
Met Office Hadley Centre, FitzRoy Road, Exeter, EX1 3PB, U.K.
Tel: +44 (0)1392 884514 Fax: +44 (0)1392 885681
E-mail: [email protected] http://www.metoffice.gov.uk
-----Original Message-----
From: [email protected] [mailto:[email protected]]
Sent: 16 March 2018 14:19
To: Jones, Chris D <[email protected]>; [email protected]
Subject: New standard names for C4MIP - part 2
Dear All,
I am proposing some further standard names for the C4MIP project in CMIP6 -
this should complete the list of quantities needed. I'm sure Chris will comment
on these in due course and any other comments and suggestions for improvement
are always welcome.
Quite a lot of these names are for nitrogen contents and fluxes in and out of
the atmosphere and various land surface components. Chris, please could you
check in particular that I have named the nitrogen species correctly in each
case? For some names I think it's fine just to say 'nitrogen' but in others I
have said inorganic_nitrogen or nitrogen_compounds_expressed_as_nitrogen
depending on what seemed most appropriate, but I may not have chosen the best
alternative in every case and I'd appreciate some advice about this.
An additional wrinkle to this is that there are two alternative pieces of text
that I could use to define nitrogen_compounds_expressed_as_nitrogen. One of
them was introduced for OMIP, i.e. ocean, nitrogen quantities:
' "Nitrogen compounds" summarizes all chemical species containing nitrogen
atoms. The list of individual species that are included in this quantity can
vary between models. Where possible, the data variable should be accompanied by
a complete description of the species represented, for example, by using a
comment attribute.'
This is generic so could easily be applied to all the nitrogen_compounds names,
but it doesn't give any hint about what individual species are actually
involved.
There is another, more detailed definition that was introduced last year for
various atmospheric nitrogen terms:
' "Nitrogen compounds" summarizes all chemical species containing nitrogen
atoms. Usually, particle bound and gaseous nitrogen compounds, such as atomic
nitrogen (N), nitrogen monoxide (NO), nitrogen dioxide (NO2), dinitrogen
pentoxide (N2O5), nitric acid (HNO3), nitrate (NO3-), peroxynitric acid (HNO4),
ammonia (NH3), ammonium (NH4+), bromine nitrate (BrONO2), chlorine nitrate
(ClONO2) and organic nitrates (most notably peroxyacetyl nitrate, sometimes
referred to as PAN, (CH3COO2NO2)) are included. The list of individual species
that are included in this quantity can vary between models. Where possible, the
data variable should be accompanied by a complete description of the species
represented, for example, by using a comment attribute.'
I have used the more detailed definition where I thought it might apply (fluxes
into/ out of the atmosphere, atmospheric tendencies) and the generic definition
elsewhere. Again, I'd appreciate advice on whether I've made the correct
choices in each case.
1. wood_debris_mass_content_of_nitrogen (kg m-2) ' "Content" indicates a
quantity per unit area. "Wood debris" means dead organic matter composed of
coarse wood. It is distinct from litter.'
2. surface_litter_mass_content_of_nitrogen (kg m-2) ' "Content" indicates a
quantity per unit area. "Litter" is dead plant material in or above the soil.
"Surface litter" means the part of the litter resting above the soil surface.'
3. subsurface_litter_mass_content_of_nitrogen (kg m-2) ' "Content" indicates a
quantity per unit area. "Litter" is dead plant material in or above the soil.
"Subsurface litter" means the part of the litter mixed within the soil below
the surface.'
4. wood_mass_content_of_nitrogen (kg m-2) ' "Content" indicates a quantity per
unit area.'
This is by analogy with the existing standard name 'wood_carbon_content'.
Although we don't currently define 'wood' in this context I am sure it means
'living wood' as opposed to wood_debris. The CMIP6 data request talks about
'stem'. I appreciate that 'stem' could refer to more than just trees, whose
stems are living wood', but I think these names are essentially trying to
describe the same thing. For this name we could perhaps even say
living_wood_mass_content_of_nitrogen (and make an alias for the carbon name so
that it follows the same pattern). What do you think?
5. leaf_mass_content_of_nitrogen (kg m-2) ' "Content" indicates a quantity per
unit area.'
6. root_mass_content_of_nitrogen (kg m-2) ' "Content" indicates a quantity per
unit area.'
7. miscellaneous_living_matter_mass_content_of_nitrogen (kg m-2) ' "Content"
indicates a quantity per unit area. "Miscellaneous living matter" means all
those parts of living vegetation that are not leaf, wood, root or other
separately named components.'
This is by analogy with the existing name
miscellaneous_living_matter_carbon_content.
8. nitrogen_mass_flux_into_soil_from_vegetation_excluding_litter (kg m-2 s-1)
'In accordance with common usage in geophysical disciplines, "flux" implies per
unit area, called "flux density" in physics. "Vegetation" means any living
plants e.g. trees, shrubs, grass. "Litter" is dead plant material in or above
the soil.'
By analogy with the existing name
carbon_mass_flux_into_soil_from_vegetation_excluding_litter.
9. nitrogen_mass_flux_into_litter_from_vegetation (kg m-2 s-1) 'In accordance
with common usage in geophysical disciplines, "flux" implies per unit area,
called "flux density" in physics. "Litter" is dead plant material in or above
the soil. "Vegetation" means any living plants e.g. trees, shrubs, grass.
10. nitrogen_mass_flux_into_soil_from_litter (kg m-2 s-1) 'In accordance with
common usage in geophysical disciplines, "flux" implies per unit area, called
"flux density" in physics. "Litter" is dead plant material in or above the
soil.'
11.
tendency_of_soil_mass_content_of_inorganic_nitrogen_expressed_as_nitrogen_due_to_fixation
(kg m-2 s-1) 'The phrase "tendency_of_X" means derivative of X with respect to
time. "Content" indicates a quantity per unit area. The "soil content" of a
quantity refers to the vertical integral from the surface down to the bottom of
the soil model. For the content between specified levels in the soil, standard
names including "content_of_soil_layer" are used. 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. "Inorganic nitrogen" describes a family of chemical species
which, in soil, usually consists of nitrate and ammonium compounds which act as
nitrogen nutrients. 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.
"Nitrogen fixation" means the production of ammonia from nitrogen gas.
Organisms that fix nitrogen are termed "diazotrophs".'
Was I right to call this one 'inorganic_nitrogen'? I borrowed the last two
sentences of the definition from an ocean name. Do they accurately describe
land based nitrogen fixation? My understanding is that 'diazotrophs' is a
general term and not confined to ocean organisms but I'd be pleased if someone
could confirm that!
12. mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_into_sea_from_rivers
(kg m-2 s-1) '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. "Nitrogen compounds" summarizes all chemical
species containing nitrogen atoms. The list of individual species that are
included in this quantity can vary between models. Where possible, the data
variable should be accompanied by a complete description of the species
represented, for example, by using a comment attribute.'
Are the nitrogen species and its definition the right ones?
13.
mass_flux_of_nox_expressed_as_nitrogen_out_of_vegetation_and_litter_and_soil
(kg m-2 s-1) '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. "Nox" means a combination of two radical
species containing nitrogen and oxygen NO+NO2. "Vegetation" means any living
plants e.g. trees, shrubs, grass. "Litter" is dead plant material in or above
the soil.'
14.
mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_out_of_vegetation_and_litter_and_soil
(kg m-2 s-1) '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. "Nitrogen compounds" summarizes all chemical
species containing nitrogen atoms. The list of individual species that are
included in this quantity can vary between models. Where possible, the data
variable should be accompanied by a complete description of the species
represented, for example, by using a comment attribute. "Vegetation" means any
living plants e.g. trees, shrubs, grass. "Litter" is dead plant material in or
above the soil.'
Are the nitrogen species and its definition the right ones?
15.
tendency_of_atmosphere_mass_content_of_reactive_nitrogen_expressed_as_nitrogen_due_to_deposition
(kg m-2 s-1) 'The phrase "tendency_of_X" means derivative of X with respect to
time. "Content" indicates a quantity per unit area. The "atmosphere content" of
a quantity refers to the vertical integral from the surface to the top of the
atmosphere. For the content between specified levels in the atmosphere,
standard names including "content_of_atmosphere_layer" are used. 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 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. "Deposition" is the sum of wet and dry deposition.'
We don't currently have any definition for 'reactive_nitrogen'. Please could
you provide one?
16.
tendency_of_soil_mass_content_of_inorganic_nitrogen_expressed_as_nitrogen_due_to_fertilization
(kg m-2 s-1) 'The phrase "tendency_of_X" means derivative of X with respect to
time. "Content" indicates a quantity per unit area. The "soil content" of a
quantity refers to the vertical integral from the surface down to the bottom of
the soil model. For the content between specified levels in the soil, standard
names including "content_of_soil_layer" are used. 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. "Inorganic nitrogen" describes a family of chemical species
which, in soil, usually consists of nitrate and ammonium compounds which act as
nitrogen nutrients. "Fertilization" means the addition of artificial
fertilizers and animal manure to soil for the purpose of increasing plant
nutrient concentrations.'
Is it right to say 'inorganic_nitrogen' for this one? Is the definition of
'fertilization' okay?
17.
surface_upward_mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_due_to_emission_from_fires
(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.
"Nitrogen compounds" summarizes all chemical species containing nitrogen atoms.
Usually, particle bound and gaseous nitrogen compounds, such as atomic nitrogen
(N), nitrogen monoxide (NO), nitrogen dioxide (NO2), dinitrogen pentoxide
(N2O5), nitric acid (HNO3), nitrate (NO3-), peroxynitric acid (HNO4), ammonia
(NH3), ammonium (NH4+), bromine nitrate (BrONO2), chlorine nitrate (ClONO2) and
organic nitrates (most notably peroxyacetyl nitrate, sometimes referred to as
PAN, (CH3COO2NO2)) are included. The list of individual species that are
included in this quantity can vary between models. Where possible, the data
variable should be accompanied by a complete description of the species
represented, for example, by using a comment attribute. 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. "Emission" means emission from a primary source
located anywhere within the atmosphere, including at the lower boundary (i.e.
the surface of the earth). "Emission" is a process entirely distinct from
"re-emission" which is used in some standard names. The term "fires" means all
biomass fires, whether naturally occurring or ignited by humans.'
Are the nitrogen species and its definition the right ones?
18.
surface_upward_mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_due_to_all_land_processes_excluding_fires
(kg m-2 s-1) ' "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.
"Nitrogen compounds" summarizes all chemical species containing nitrogen atoms.
Usually, particle bound and gaseous nitrogen compounds, such as atomic nitrogen
(N), nitrogen monoxide (NO), nitrogen dioxide (NO2), dinitrogen pentoxide
(N2O5), nitric acid (HNO3), nitrate (NO3-), peroxynitric acid (HNO4), ammonia
(NH3), ammonium (NH4+), bromine nitrate (BrONO2), chlorine nitrate (ClONO2) and
organic nitrates (most notably peroxyacetyl nitrate, sometimes referred to as
PAN, (CH3COO2NO2)) are included. The list of individual species that are
included in this quantity can vary between models. Where possible, the data
variable should be accompanied by a complete description of the species
represented, for example, by using a comment attribute. 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. "All land processes" means plant and soil
respiration, photosynthesis, animal grazing, crop harvesting, natural fires and
anthropogenic land use change.'
This one is by analogy with the existing names
surface_net_downward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_all_land_processes
and
surface_net_downward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_all_land_processes_excluding_anthropogenic_land_use_change.
Are the nitrogen species and its definition the right ones?
19.
tendency_of_atmosphere_mass_content_of_nitrogen_compounds_expressed_as_nitrogen_due_to_anthropogenic_land_use_or_land_cover_change
(kg m-2 s-1) 'The phrase "tendency_of_X" means derivative of X with respect to
time. "Content" indicates a quantity per unit area. The "atmosphere content" of
a quantity refers to the vertical integral from the surface to the top of the
atmosphere. For the content between specified levels in the atmosphere,
standard names including "content_of_atmosphere_layer" are used. 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 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. "Nitrogen compounds" summarizes all chemical species containing
nitrogen atoms. Usually, particle bound and gaseous nitrogen compounds, such as
atomic nitrogen (N), nitrogen monoxide (NO), nitrogen dioxide (NO2), dinitrogen
pentoxide (N2O5), nitric acid (HNO3), nitrate (NO3-), peroxynitric acid (HNO4),
ammonia (NH3), ammonium (NH4+), bromine nitrate (BrONO2), chlorine nitrate
(ClONO2) and organic nitrates (most notably peroxyacetyl nitrate, sometimes
referred to as PAN, (CH3COO2NO2)) are included. The list of individual species
that are included in this quantity can vary between models. Where possible, the
data variable should be accompanied by a complete description of the species
represented, for example, by using a comment attribute. 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 includes fires ignited by humans for the
purpose of land use change and the processes of eventual disposal and
decomposition of wood products such as paper, cardboard, furniture and timber
for construction.'
Are the nitrogen species and its definition the right ones?
20.
nitrogen_mass_flux_into_forestry_and_agricultural_products_due_to_anthropogenic_land_use_or_land_cover_change
(kg m-2 s-1) 'In accordance with common usage in geophysical disciplines,
"flux" implies per unit area, called "flux density" in physics. Examples of
"forestry and agricultural products" are paper, cardboard, furniture, timber
for construction, biofuels and food for both humans and livestock. Models that
simulate land use changes have one or more pools of nitrogen that represent
these products in order to conserve nitrogen and allow its eventual release
into the atmosphere, for example, when the products decompose in landfill
sites. "Anthropogenic" means influenced, caused, or created by human activity.
"Anthropogenic land use change" means human changes to land, excluding forest
regrowth. It includes fires ignited by humans for the purpose of land use
change and the processes of eventual disposal and decomposition of wood
products such as paper, cardboard, furniture and timber for construction.'
21. surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_wood (kg m-2
s-1) ' "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 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. Plant respiration is
the sum of respiration by parts of plants both above and below the soil. Plants
which photosynthesise are autotrophs i.e. "producers" of the biomass which they
respire from inorganic precursors using sunlight for energy.'
As for proposal (4), 'wood' means living wood. (We should adopt consistent
terminology for both). There are existing names for plant respiration -
'plants' is currently the term used in standard names for 'autotrophs'.
22. surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_leaves (kg
m-2 s-1) ' "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 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. Plant
respiration is the sum of respiration by parts of plants both above and below
the soil. Plants which photosynthesise are autotrophs i.e. "producers" of the
biomass which they respire from inorganic precursors using sunlight for energy.'
23. surface_upward_mass_flux_of_carbon_due_to_plant_respiration_in_roots (kg
m-2 s-1) ' "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 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. Plant
respiration is the sum of respiration by parts of plants both above and below
the soil. Plants which photosynthesise are autotrophs i.e. "producers" of the
biomass which they respire from inorganic precursors using sunlight for energy.'
24.
net_primary_productivity_of_biomass_expressed_as_carbon_accumulated_in_miscellaneous_living_matter
(kg m-2 s-1) ' "Miscellaneous living matter" means all those parts of living
vegetation that are not leaf, wood, root or other separately named components.
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. "Production of carbon" means
the production of biomass expressed as the mass of carbon which it contains.
Net primary production is the excess of gross primary production (rate of
synthesis of biomass from inorganic precursors) by autotrophs ("producers"),
for example, photosynthesis in plants or phytoplankton, over the rate at which
the autotrophs themselves respire some of this biomass. "Productivity" means
production per unit area.'
25.
surface_upward_mass_flux_of_carbon_due_to_heterotrophic_respiration_in_litter
(kg m-2 s-1) ' "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 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. "Litter" is
dead plant material in or above the soil. Heterotrophic respiration is
respiration by heterotrophs ("consumers"), which are organisms (including
animals and decomposers) that consume other organisms or dead organic material,
rather than synthesising organic material from inorganic precursors using
energy from the environment (especially sunlight) as autotrophs ("producers")
do. Heterotrophic respiration goes on both above and within the soil.'
We have one existing name for 'heterotrophic_respiration'.
26. surface_upward_mass_flux_of_carbon_due_to_heterotrophic_respiration_in_soil
(kg m-2 s-1) ' "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 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.
Heterotrophic respiration is respiration by heterotrophs ("consumers"), which
are organisms (including animals and decomposers) that consume other organisms
or dead organic material, rather than synthesising organic material from
inorganic precursors using energy from the environment (especially sunlight) as
autotrophs ("producers") do. Heterotrophic respiration goes on both above and
within the soil.'
27. soil_pool_carbon_decay_rate (kg m-2 s-1) ' "Soil carbon" is the organic
matter present in soil quantified by the mass of carbon it contains. Soil
carbon is returned to the atmosphere as the organic matter decays. The decay
process takes varying amounts of time depending on the composition of the
organic matter, the temperature and the availability of moisture. A carbon
"soil pool" means the carbon contained in organic matter which has a
characteristic period over which it decays and releases carbon into the
atmosphere.'
This is a new quantity, although we do have some existing names that refer to
soil_pools. I guessed the unit from the quantity - is it correct?
28. mass|mole_concentration_of_carbon_dioxide_passive_tracer_in_air
What are the units of this quantity? Knowing the unit will allow us to decide
if this should be a mass or a mole concentration (or something else). I wasn't
really sure of the purpose of this name - by using carbon dioxide as a tracer I
assume that means it is conserved by being treated as chemically inert. Can you
give me some more details about this one please?
Best wishes,
Alison
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