SMTGYH2X tendency_of_specific_humidity_due_to_stratiform_cloud_and_precipitation The phrase "tendency_of_X" means derivative of X with respect to time. "Specific" means per unit mass. Specific humidity is the mass fraction of water vapor in (moist) air. 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. A variable with the standard name of tendency_of_specific_humidity_due_to_stratiform_cloud_and_precipitation should contain the effects of all processes which convert stratiform clouds and precipitation to or from water vapor. In an atmosphere model, stratiform cloud is that produced by large-scale convergence (not the convection schemes). I 3OOI1V0U sea_water_added_potential_temperature The quantity with standard name sea_water_added_potential_temperature is a passive tracer in an ocean model whose surface flux does not come from the atmosphere but is imposed externally upon the simulated climate system. The surface flux is expressed as a heat flux and converted to a passive tracer increment as if it were a heat flux being added to potential temperature. The passive tracer is transported within the ocean as if it were potential temperature. The passive tracer is zero in the control climate of the model. The passive tracer records added heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas. Potential temperature is the temperature a parcel of air or sea water would have if moved adiabatically to sea level pressure. I TNBLPUM0 tendency_of_air_temperature_due_to_stratiform_cloud_and_precipitation The phrase "tendency_of_X" means derivative of X with respect to time. Air temperature is the bulk temperature of the air, not the surface (skin) temperature. 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. A variable with the standard name tendency_of_air_temperature_due_to_stratiform_cloud_and_precipitation should contain net latent heating effects of all processes which convert stratiform clouds and precipitation between water vapour, liquid or ice phases. In an atmosphere model, stratiform cloud is that produced by large-scale convergence (not the convection schemes). I EOU697N7 tendency_of_air_temperature_due_to_boundary_layer_mixing The phrase "tendency_of_X" means derivative of X with respect to time. Air temperature is the bulk temperature of the air, not the surface (skin) temperature. 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. I 9SAN6SZV effective_radius_of_stratiform_cloud_liquid_water_particle_at_stratiform_liquid_water_cloud_top The effective radius of a size distribution of particles, such as aerosols, cloud droplets or ice crystals, is the area weighted mean radius of particle size. It is calculated as the ratio of the third to the second moment of the particle size distribution. The phrase "stratiform_liquid_water_cloud_top" refers to the top of the highest stratiform liquid water cloud. In an atmosphere model, stratiform cloud is that produced by large-scale convergence (not the convection schemes). I BONZCG5H tendency_of_specific_humidity_due_to_boundary_layer_mixing The phrase "tendency_of_X" means derivative of X with respect to time. "Specific" means per unit mass. Specific humidity is the mass fraction of water vapor in (moist) air. 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. I 1TOUSBQ7 land_ice_mass_not_displacing_sea_water "Land ice not displacing sea water" means land ice that would not alter sea level if the ice were converted to water and added to the ocean. It excludes ice shelves (and any other sort of floating ice) and it excludes a fraction of grounded ice-sheet mass equivalent to the mass of any sea water it displaces. It includes glaciers and a portion of grounded ice-sheet mass exceeding the mass of any sea water displaced. The quantity with standard name land_ice_mass_not_displacing_sea_water is the total mass integrated over an area of land ice. The geographical extent of the ice over which the mass was calculated should be described by providing bounds on the horizontal coordinate variable or scalar with the standard name of "region" supplied according to section 6.1.1 of the CF convention. I IDWENXCE number_concentration_of_stratiform_cloud_liquid_water_particle_at_stratiform_liquid_water_cloud_top "Number concentration" means the number of particles or other specified objects per unit volume. The phrase "stratiform_liquid_water_cloud_top" refers to the top of the highest stratiform liquid water cloud. In an atmosphere model, stratiform cloud is that produced by large-scale convergence (not the convection schemes). I VZQCHS2G land_ice_mass "Land ice" means glaciers, ice-caps and ice-sheets resting on bedrock and also includes ice-shelves. The horizontal domain over which the quantity is calculated is described by the associated coordinate variables and coordinate bounds or by a coordinate variable or scalar coordinate variable with the standard name of "region" supplied according to section 6.1.1 of the CF conventions. I H398WTKV surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_miscellaneous_living_matter 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 chemical formula for carbon dioxide is CO2. 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. Plant respiration is the sum of respiration by parts of plants both above and below the soil. It is assumed that all the respired carbon dioxide is emitted to the atmosphere. The term "plants" refers to the kingdom of plants in the modern classification which excludes fungi. Plants are autotrophs i.e. "producers" of biomass using carbon obtained from carbon dioxide. "Miscellaneous living matter" means all those parts of plants that are not leaf, stem, root or other separately named components. I 3707OQB4 sea_water_redistributed_conservative_temperature The quantity with standard name sea_water_redistributed_conservative_temperature is a passive tracer in an ocean model which is subject to an externally imposed perturbative surface heat flux. The passive tracer is initialised to the conservative temperature in the control climate before the perturbation is imposed. Its surface flux is the heat flux from the atmosphere, not including the imposed perturbation, and is converted to a passive tracer increment as if it were being added to conservative temperature. The passive tracer is transported within the ocean as if it were conservative temperature. The passive tracer records redistributed heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas. Conservative Temperature is defined as part of the Thermodynamic Equation of Seawater 2010 (TEOS-10) which was adopted in 2010 by the International Oceanographic Commission (IOC). Conservative Temperature is specific potential enthalpy (which has the standard name sea_water_specific_potential_enthalpy) divided by a fixed value of the specific heat capacity of sea water, namely cp_0 = 3991.86795711963 J kg-1 K-1. Conservative Temperature is a more accurate measure of the "heat content" of sea water, by a factor of one hundred, than is potential temperature. Because of this, it can be regarded as being proportional to the heat content of sea water per unit mass. Reference: www.teos-10.org; McDougall, 2003 doi: 10.1175/1520-0485(2003)033<0945:PEACOV>2.0.CO;2. I 3V2STZEX sea_water_redistributed_potential_temperature The quantity with standard name sea_water_redistributed_potential_temperature is a passive tracer in an ocean model which is subject to an externally imposed perturbative surface heat flux. The passive tracer is initialised to the potential temperature in the control climate before the perturbation is imposed. Its surface flux is the heat flux from the atmosphere, not including the imposed perturbation, and is converted to a passive tracer increment as if it were being added to potential temperature. The passive tracer is transported within the ocean as if it were potential temperature. The passive tracer records redistributed heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas. Potential temperature is the temperature a parcel of air or sea water would have if moved adiabatically to sea level pressure. I CFSN0641 heterotrophic_respiration_carbon_flux "Respiration carbon" refers to the rate at which biomass is respired expressed as the mass of carbon which it contains. 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. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. D PPMSXAF8 surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_heterotrophic_respiration 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 chemical formula for carbon dioxide is CO2. 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. 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. I WF3PJDFK surface_litter_mass_content_of_nitrogen "Content" indicates a quantity per unit area. "Litter" is dead plant material in or above the soil. It is distinct from coarse wood debris. The precise distinction between "fine" and "coarse" is model dependent. "Surface litter" means the part of the litter resting above the soil surface. The sum of the quantities with standard names wood_debris_mass_content_of_nitrogen, surface_litter_mass_content_of_nitrogen and subsurface_litter_mass_content_of_nitrogen is the total nitrogen mass content of dead plant material. I GI95T1NL surface_upward_mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_due_to_emission_from_fires 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. 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. I CFV16A50 surface_upward_carbon_mass_flux_due_to_plant_respiration_for_biomass_growth "Upward" indicates a vector component which is positive when directed upward (negative downward). 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. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. The surface called "surface" means the lower boundary of the atmosphere. 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. D 65PHTU2D surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_for_biomass_growth 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 chemical formula for carbon dioxide is CO2. 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. Plant respiration is the sum of respiration by parts of plants both above and below the soil. It is assumed that all the respired carbon dioxide is emitted to the atmosphere. The term "plants" refers to the kingdom of plants in the modern classification which excludes fungi. Plants are autotrophs i.e. "producers" of biomass using carbon obtained from carbon dioxide. I N1DP5O1H nitrogen_mass_flux_into_forestry_and_agricultural_products_due_to_anthropogenic_land_use_or_land_cover_change 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. I PB6R50XR stem_mass_content_of_nitrogen "Content" indicates a quantity per unit area. The stem of a plant is the axis that bears buds and shoots with leaves and, at its basal end, roots. Its function is to carry water and nutrients. Examples include the stalk of a plant or the main trunk of a tree. I 16ZV88FT surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_roots 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 chemical formula for carbon dioxide is CO2. 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. 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. I 76LWI9UK surface_upward_mass_flux_of_methane_due_to_emission_from_wetland_biological_production 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 chemical formula for methane is CH4. The mass is the total mass of the molecules. The phrase "tendency_of_X" means derivative of X with respect to time. 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. Wetlands are areas where water covers the soil, or is present either at or near the surface of the soil all year or for varying periods of time during the year, including during the growing season. The precise conditions under which wetlands produce and consume methane can vary between models. I D32N6YZZ surface_upward_mass_flux_of_nox_expressed_as_nitrogen_out_of_vegetation_and_litter_and_soil 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. "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. I CFV16A46 surface_litter_carbon_content "Content" indicates a quantity per unit area. "Litter carbon" is dead plant material in or above the soil quantified as the mass of carbon which it contains. The surface called "surface" means the lower boundary of the atmosphere. D 2MY21HA6 surface_litter_mass_content_of_carbon "Litter" is dead plant material in or above the soil. It is distinct from coarse wood debris. The precise distinction between "fine" and "coarse" is model dependent. "Surface litter" means the part of the litter resting above the soil surface. "Content" indicates a quantity per unit area. The sum of the quantities with standard names surface_litter_mass_content_of_carbon and subsurface_litter_mass_content_of_carbon has the standard name litter_mass_content_of_carbon. I CFSN0604 litter_carbon_content "Content" indicates a quantity per unit area. "Litter carbon" is dead inorganic material in or above the soil quantified as the mass of carbon which it contains. D Z8MNYOFO litter_mass_content_of_carbon "Litter" is dead plant material in or above the soil. It is distinct from coarse wood debris. The precise distinction between "fine" and "coarse" is model dependent. "Content" indicates a quantity per unit area. The sum of the quantities with standard names surface_litter_mass_content_of_carbon and subsurface_litter_mass_content_of_carbon has the standard name litter_mass_content_of_carbon. I H0JTDQKT surface_upward_mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_out_of_vegetation_and_litter_and_soil 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. 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. I 2KZV2XTK nitrogen_mass_flux_into_soil_from_vegetation_excluding_litter 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. I U7YYXJ2T subsurface_litter_mass_content_of_nitrogen "Content" indicates a quantity per unit area. "Litter" is dead plant material in or above the soil. It is distinct from coarse wood debris. The precise distinction between "fine" and "coarse" is model dependent. "Subsurface litter" means the part of the litter mixed within the soil below the surface. The sum of the quantities with standard names wood_debris_mass_content_of_nitrogen, surface_litter_mass_content_of_nitrogen and subsurface_litter_mass_content_of_nitrogen is the total nitrogen mass content of dead plant material. I 7231AYLJ surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_stems 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 chemical formula for carbon dioxide is CO2. 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. 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. The stem of a plant is the axis that bears buds and shoots with leaves and, at its basal end, roots. Its function is to carry water and nutrients. Examples include the stalk of a plant or the main trunk of a tree. I Q0PYW5XC root_mass_content_of_nitrogen "Content" indicates a quantity per unit area. I HBLPLTWJ mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_into_sea_from_rivers 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. I J3GXAOH3 mass_fraction_of_carbon_dioxide_tracer_in_air The chemical formula for carbon dioxide is CO2. Mass fraction is used in the construction "mass_fraction_of_X_in_Y", where X is a material constituent of Y. It means the ratio of the mass of X to the mass of Y (including X). A chemical species denoted by X may be described by a single term such as "nitrogen" or a phrase such as "nox_expressed_as_nitrogen". A "tracer" is a quantity advected by a model to facilitate analysis of flow patterns. I EV1FU5HF surface_downward_mass_flux_of_carbon14_dioxide_abiotic_analogue_expressed_as_carbon The surface called "surface" means the lower boundary of the atmosphere. "Downward" indicates a vector component which is positive when directed downward (negative upward). In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. In ocean biogeochemistry models, an "abiotic analogue" is used to simulate the effect on a modelled variable when biological effects on ocean carbon concentration and alkalinity are ignored. 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. Carbon14 is a radioactive isotope of carbon having six protons and eight neutrons, used in radiocarbon dating. D KXO1F55H surface_downward_mass_flux_of_14C_dioxide_abiotic_analogue_expressed_as_carbon The surface called "surface" means the lower boundary of the atmosphere. "Downward" indicates a vector component which is positive when directed downward (negative upward). In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. In ocean biogeochemistry models, an "abiotic analogue" is used to simulate the effect on a modelled variable when biological effects on ocean carbon concentration and alkalinity are ignored. 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. "C" means the element carbon and "14C" is the radioactive isotope "carbon-14", having six protons and eight neutrons and used in radiocarbon dating. I FROZ28YJ tendency_of_soil_mass_content_of_nitrogen_compounds_expressed_as_nitrogen_due_to_fertilization 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. "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. "Fertilization" means the addition of artificial fertilizers and animal manure to soil for the purpose of increasing plant nutrient concentrations. I QGOOLVIF surface_upward_mass_flux_of_carbon_due_to_heterotrophic_respiration_in_soil "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 within both the soil and litter pools. I Z66PQSKM sea_water_added_conservative_temperature The quantity with standard name sea_water_added_conservative_temperature is a passive tracer in an ocean model whose surface flux does not come from the atmosphere but is imposed externally upon the simulated climate system. The surface flux is expressed as a heat flux and converted to a passive tracer increment as if it were a heat flux being added to conservative temperature. The passive tracer is transported within the ocean as if it were conservative temperature. The passive tracer is zero in the control climate of the model. The passive tracer records added heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas. Conservative Temperature is defined as part of the Thermodynamic Equation of Seawater 2010 (TEOS-10) which was adopted in 2010 by the International Oceanographic Commission (IOC). Conservative Temperature is specific potential enthalpy (which has the standard name sea_water_specific_potential_enthalpy) divided by a fixed value of the specific heat capacity of sea water, namely cp_0 = 3991.86795711963 J kg-1 K-1. Conservative Temperature is a more accurate measure of the "heat content" of sea water, by a factor of one hundred, than is potential temperature. Because of this, it can be regarded as being proportional to the heat content of sea water per unit mass. Reference: www.teos-10.org; McDougall, 2003 doi: 10.1175/1520-0485(2003)033<0945:PEACOV>2.0.CO;2. I MKWOPHDH miscellaneous_living_matter_mass_content_of_nitrogen "Content" indicates a quantity per unit area. "Miscellaneous living matter" means all those parts of plants that are not leaf, stem, root or other separately named components. The term "plants" refers to the kingdom of plants in the modern classification which excludes fungi. Plants are autotrophs i.e. "producers" of biomass using carbon obtained from carbon dioxide. I 99NA57YY net_primary_productivity_of_biomass_expressed_as_carbon_accumulated_in_miscellaneous_living_matter "Miscellaneous living matter" means all those parts of plants that are not leaf, stem, root or other separately named components. The term "plants" refers to the kingdom of plants in the modern classification which excludes fungi. Plants are autotrophs i.e. "producers" of biomass using carbon obtained from carbon dioxide. 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. I 0BQS2R11 number_concentration_of_convective_cloud_liquid_water_particle_at_convective_liquid_water_cloud_top "Number concentration" means the number of particles or other specified objects per unit volume.The phrase "convective_liquid_water_cloud_top" refers to the top of the highest convective liquid water cloud. Convective cloud is that produced by the convection schemes in an atmosphere model. I CFV16A43 subsurface_litter_carbon_content "Content" indicates a quantity per unit area. "Litter carbon" is dead plant material in or above the soil quantified as the mass of carbon which it contains. The surface called "surface" means the lower boundary of the atmosphere. D WBEUZ46B subsurface_litter_mass_content_of_carbon "Litter" is dead plant material in or above the soil. It is distinct from coarse wood debris. The precise distinction between "fine" and "coarse" is model dependent. "Subsurface litter" means the part of the litter mixed within the soil below the surface. "Content" indicates a quantity per unit area. The sum of the quantities with standard names surface_litter_mass_content_of_carbon and subsurface_litter_mass_content_of_carbon has the standard name litter_mass_content_of_carbon. I 85AKQID1 surface_upward_mass_flux_of_nitrogen_compounds_expressed_as_nitrogen_due_to_all_land_processes_excluding_fires "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. 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. I CBL1J5J8 surface_upward_mass_flux_of_carbon_due_to_heterotrophic_respiration_in_litter "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 within both the soil and litter pools. I BAKDTIT0 tendency_of_atmosphere_mass_content_of_nitrogen_compounds_expressed_as_nitrogen_due_to_anthropogenic_land_use_or_land_cover_change 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. 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. I NK7W2T5M sea_binary_mask X"_binary_mask" has 1 where condition X is met, 0 elsewhere. 1 = sea, 0 = land. I 7UFCTGRK nitrogen_mass_flux_into_soil_from_litter 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. I UROY29L6 tendency_of_soil_and_vegetation_mass_content_of_nitrogen_compounds_expressed_as_nitrogen_due_to_fixation The phrase "tendency_of_X" means derivative of X with respect to time. "Content" indicates a quantity per unit area. On land, "nitrogen fixation" means the uptake of nitrogen gas directly from the atmosphere. The representation of fixed nitrogen is model dependent, with the nitrogen entering either vegetation, soil or both. "Vegetation" means any living plants e.g. trees, shrubs, grass. 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. 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. I CFSN0480 plant_respiration_carbon_flux "Respiration carbon" refers to the rate at which biomass is respired expressed as the mass of carbon which it contains. 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. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. D 067HJZRA surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration 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 chemical formula for carbon dioxide is CO2. 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. Plant respiration is the sum of respiration by parts of plants both above and below the soil. It is assumed that all the respired carbon dioxide is emitted to the atmosphere. The term "plants" refers to the kingdom of plants in the modern classification which excludes fungi. Plants are autotrophs i.e. "producers" of biomass using carbon obtained from carbon dioxide. I SX7WWXXE soil_pool_carbon_decay_rate "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. Each modelled soil carbon pool has a characteristic turnover time, which is modified by environmental conditions such as temperature and moisture so that the turnover time varies in space and time. The quantity with standard name soil_pool_carbon_decay_rate is defined as 1/(turnover time). The data variable should be accompanied by a string valued coordinate variable or scalar coordinate variable with standard name soil_pool. I 3B2JG9UV mole_concentration_of_dissolved_inorganic_carbon13_in_sea_water 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". "Dissolved inorganic carbon" describes a family of chemical species in solution, including carbon dioxide, carbonic acid and the carbonate and bicarbonate anions. "Dissolved inorganic carbon" is the term used in standard names for all species belonging to the family that are represented within a given model. The list of individual species that are included in a quantity having a group chemical standard name 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. Carbon13 is a stable isotope of carbon having six protons and seven neutrons. D DORXA6DP mole_concentration_of_dissolved_inorganic_13C_in_sea_water 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". "Dissolved inorganic carbon" describes a family of chemical species in solution, including carbon dioxide, carbonic acid and the carbonate and bicarbonate anions. "Dissolved inorganic carbon" is the term used in standard names for all species belonging to the family that are represented within a given model. The list of individual species that are included in a quantity having a group chemical standard name 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. "C" means the element carbon and "13C" is the stable isotope "carbon-13", having six protons and seven neutrons. I GA6K2IBR wood_debris_mass_content_of_nitrogen "Content" indicates a quantity per unit area. "Wood debris" means dead organic matter composed of coarse wood. It is distinct from fine litter. The precise distinction between "fine" and "coarse" is model dependent. The sum of the quantities with standard names wood_debris_mass_content_of_nitrogen, surface_litter_mass_content_of_nitrogen and subsurface_litter_mass_content_of_nitrogen is the total nitrogen mass content of dead plant material. I SUJ756R0 tendency_of_land_ice_mass_due_to_basal_mass_balance "Land ice" means glaciers, ice-caps and ice-sheets resting on bedrock and also includes ice-shelves. "tendency_of_X" means derivative of X with respect to time. 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. Mass balance means the net rate at which ice is accumulated. A negative value means loss of ice. The tendency in ice mass due to the basal mass balance is the spatial integral of the quantity with standard name land_ice_basal_specific_mass_balance_flux. The geographical extent of the ice over which the mass is calculated is defined by the horizontal coordinates and any associated coordinate bounds or by a string valued auxiliary coordinate variable with a standard name of "region". M Q208CGIT nitrogen_mass_flux_into_litter_from_vegetation 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. I UMZS988Y mole_concentration_of_dissolved_inorganic_carbon14_in_sea_water 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". "Dissolved inorganic carbon" describes a family of chemical species in solution, including carbon dioxide, carbonic acid and the carbonate and bicarbonate anions. "Dissolved inorganic carbon" is the term used in standard names for all species belonging to the family that are represented within a given model. The list of individual species that are included in a quantity having a group chemical standard name 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. Carbon14 is a radioactive isotope of carbon having six protons and eight neutrons, used in radiocarbon dating. D 9HADKG3D mole_concentration_of_dissolved_inorganic_14C_in_sea_water 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". "Dissolved inorganic carbon" describes a family of chemical species in solution, including carbon dioxide, carbonic acid and the carbonate and bicarbonate anions. "Dissolved inorganic carbon" is the term used in standard names for all species belonging to the family that are represented within a given model. The list of individual species that are included in a quantity having a group chemical standard name 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. "C" means the element carbon and "14C" is the radioactive isotope "carbon-14", having six protons and eight neutrons and used in radiocarbon dating. I CFSN0352 soil_respiration_carbon_flux "Respiration carbon" refers to the rate at which biomass is respired expressed as the mass of carbon which it contains. Soil respiration is the sum of respiration in the soil by animals and decomposers of litter (heterotrophs or "consumers"), which have not produced the biomass they respire, and respiration by the roots of plants (autotrophs or "producers"), which have themselves produced the biomass they respire. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. D RTIXFQZ3 surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_respiration_in_soil 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 chemical formula for carbon dioxide is CO2. 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. Soil respiration is the sum of respiration in the soil by animals and decomposers of litter (heterotrophs or "consumers"), which have not produced the biomass they respire, and respiration by the roots of plants (autotrophs or "producers"), which have themselves produced the biomass they respire. I 5O10JWUW tendency_of_land_ice_mass_due_to_surface_mass_balance "Land ice" means glaciers, ice-caps and ice-sheets resting on bedrock and also includes ice-shelves. The phrase "tendency_of_X" means derivative of X with respect to time. The surface called "surface" means the lower boundary of the atmosphere. 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. "Mass balance" means the net rate at which ice is added. A negative value means loss of ice. The tendency in ice mass due to the surface mass balance is the spatial integral of the quantity with standard name land_ice_surface_specific_mass_balance_flux. The horizontal domain over which the quantity is described by the associated coordinate variables and coordinate bounds or by a string valued coordinate variable or scalar coordinate variable with a standard name of "region". I FHMB0C0Z surface_downward_mass_flux_of_carbon13_dioxide_abiotic_analogue_expressed_as_carbon13 The surface called "surface" means the lower boundary of the atmosphere. "Downward" indicates a vector component which is positive when directed downward (negative upward). In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. In ocean biogeochemistry models, an "abiotic analogue" is used to simulate the effect on a modelled variable when biological effects on ocean carbon concentration and alkalinity are ignored. 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. Carbon13 is a stable isotope of carbon having six protons and seven neutrons. D 19EPEI15 surface_downward_mass_flux_of_13C_dioxide_abiotic_analogue_expressed_as_13C The surface called "surface" means the lower boundary of the atmosphere. "Downward" indicates a vector component which is positive when directed downward (negative upward). In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. In ocean biogeochemistry models, an "abiotic analogue" is used to simulate the effect on a modelled variable when biological effects on ocean carbon concentration and alkalinity are ignored. 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. "C" means the element carbon and "13C" is the stable isotope "carbon-13", having six protons and seven neutrons. I CFV16A68 wood_debris_carbon_content "Content" indicates a quantity per unit area. "Wood debris" means dead organic matter composed of coarse wood. It is distinct from litter. D QDSSNHQK wood_debris_mass_content_of_carbon "Content" indicates a quantity per unit area. "Wood debris" means dead organic matter composed of coarse wood. It is distinct from fine litter. The precise distinction between "fine" and "coarse" is model dependent. The sum of the quantities with standard names wood_debris_mass_content_of_nitrogen, surface_litter_mass_content_of_nitrogen and subsurface_litter_mass_content_of_nitrogen is the total nitrogen mass content of dead plant material. I MELTCMTU soil_pool A variable with the standard name of soil_pool contains strings which indicate the character of the soil pool classified according to the decay rate of the organic carbon material it contains. These strings are have not yet been standardised. I VANF5FEN leaf_mass_content_of_nitrogen "Content" indicates a quantity per unit area. I JBIEE1L0 tendency_of_land_ice_mass_due_to_calving "Land ice" means glaciers, ice-caps and ice-sheets resting on bedrock and also includes ice-shelves. "tendency_of_X" means derivative of X with respect to time. 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. The tendency in ice mass due to calving is the spatial integral of the quantity named land_ice_specific_mass_flux_due_to_calving. The geographical extent over which the quantity is calculated is defined by the horizontal coordinates and any associated coordinate bounds or by a string valued auxiliary coordinate variable with a standard name of "region". M CFV16A51 surface_upward_carbon_mass_flux_due_to_plant_respiration_for_biomass_maintenance "Upward" indicates a vector component which is positive when directed upward (negative downward). 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. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. The surface called "surface" means the lower boundary of the atmosphere. 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. D FBG5PV67 surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_for_biomass_maintenance 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 chemical formula for carbon dioxide is CO2. 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. Plant respiration is the sum of respiration by parts of plants both above and below the soil. It is assumed that all the respired carbon dioxide is emitted to the atmosphere. The term "plants" refers to the kingdom of plants in the modern classification which excludes fungi. Plants are autotrophs i.e. "producers" of biomass using carbon obtained from carbon dioxide. I CFV16A67 wood_carbon_content "Content" indicates a quantity per unit area. D QHQLM3BE stem_mass_content_of_carbon "Content" indicates a quantity per unit area. The stem of a plant is the axis that bears buds and shoots with leaves and, at its basal end, roots. Its function is to carry water and nutrients. Examples include the stalk of a plant or the main trunk of a tree. I CFV13N26 surface_ratio_of_upwelling_radiance_emerging_from_sea_water_to_downwelling_radiative_flux_in_air The surface called "surface" means the lower boundary of the atmosphere. The phrase "ratio_of_X_to_Y" means X/Y. Upwelling radiation is radiation from below. It does not mean "net upward". Downwelling radiation is radiation from above. It does not mean "net downward". Radiance is the radiative flux in a particular direction, per unit of solid angle. The direction towards which it is going must be specified, for instance with a coordinate of angle_of_emergence. Radiative flux is the sum of shortwave and longwave radiative fluxes. When thought of as being incident on a surface, a radiative flux is sometimes called "irradiance". In relation to satellite ocean color products the quantity named surface_ratio_of_upwelling_radiance_emerging_from_sea_water_to_downwelling_radiative_flux_in_air is sometimes called "remote sensing reflectance" and has a bidirectional dependence. The direction of the downwelling flux can be specified using a coordinate with the standard name angle_of_incidence. M JY28LLT8 mass_flux_of_carbon_into_forestry_and_agricultural_products_due_to_crop_harvesting 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 carbon that represent these products in order to conserve carbon and allow its eventual release into the atmosphere, for example, when the products decompose in landfill sites. 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. The definition of "crop" is model dependent, for example, some models may include fruit trees, trees grown for timber or other types of agricultural and forestry planting as crops. Crop harvesting means the human activity of collecting plant materials for the purpose of turning them into forestry or agricultural products. I CFV16A34 root_carbon_content "Content" indicates a quantity per unit area. D UKJ8WY6A root_mass_content_of_carbon "Content" indicates a quantity per unit area. I CFV16A20 miscellaneous_living_matter_carbon_content "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. D WFN37VJ8 miscellaneous_living_matter_mass_content_of_carbon "Content" indicates a quantity per unit area. "Miscellaneous living matter" means all those parts of plants that are not leaf, stem, root or other separately named components. The term "plants" refers to the kingdom of plants in the modern classification which excludes fungi. Plants are autotrophs i.e. "producers" of biomass using carbon obtained from carbon dioxide. I CFSN0091 vegetation_carbon_content "Content" indicates a quantity per unit area. "Vegetation" means any plants e.g. trees, shrubs, grass. M EVKFM0BL carbon_content_of_forestry_and_agricultural_products "Content" indicates a quantity per unit area. 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 carbon that represent these products in order to conserve carbon and allow its eventual release into the atmosphere, for example, when the products decompose in landfill sites. D 8PSGY4EL carbon_mass_content_of_forestry_and_agricultural_products "Content" indicates a quantity per unit area. 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 carbon that represent these products in order to conserve carbon and allow its eventual release into the atmosphere, for example, when the products decompose in landfill sites. I CFV16A42 slow_soil_pool_carbon_content "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. "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. "Slow soil pool" refers to the decay of organic matter in soil with a characteristic period of more than a hundred years under reference climate conditions of a temperature of 20 degrees Celsius and no water limitations. D I5DGQM0D slow_soil_pool_mass_content_of_carbon "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. 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. "Slow soil pool" refers to the decay of organic matter in soil with a characteristic period of more than a hundred years under reference climate conditions of a temperature of 20 degrees Celsius and no water limitations. I CFSN0148 tendency_of_northward_wind_due_to_gravity_wave_drag The phrase "tendency_of_X" means derivative of X with respect to time. "Northward" indicates a vector component which is positive when directed northward (negative southward). Wind is defined as a two-dimensional (horizontal) air velocity vector, with no vertical component. (Vertical motion in the atmosphere has the standard name upward_air_velocity). 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. The quantity with standard name tendency_of_northward_wind_due_to_gravity_wave_drag is the total tendency of the northward wind due to gravity waves. It is the sum of the tendencies due to orographic and nonorographic gravity waves which have the standard names tendency_of_northward_wind_due_to_orographic_gravity_wave_drag and tendency_of_northward_wind_due_to_nonorographic_gravity_wave_drag, respectively. M CFV9S4 northward_transformed_eulerian_mean_air_velocity "Northward" indicates a vector component which is positive when directed northward (negative southward). The "Transformed Eulerian Mean" refers to a formulation of the mean equations which incorporates some eddy terms into the definition of the mean, described in Andrews et al (1987): Middle Atmospheric Dynamics. Academic Press. M CFSN0346 soil_carbon_content "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. D QKPDOSQJ soil_mass_content_of_carbon "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. I CFV16A16 leaf_carbon_content "Content" indicates a quantity per unit area. D IBL3SXY3 leaf_mass_content_of_carbon "Content" indicates a quantity per unit area. I 9Z75YM9M land_ice_basal_drag "Land ice" means glaciers, ice-caps and ice-sheets resting on bedrock and also includes ice-shelves. Basal drag is a resistive stress opposing ice flow at the ice bedrock boundary. I BKHRL40U square_of_sea_surface_salinity The phrase "square_of_X" means X*X. Sea surface salinity is the salt concentration of sea water close to the sea surface, often on the Practical Salinity Scale of 1978. However, the unqualified term 'salinity' is generic and does not necessarily imply any particular method of calculation. The units of salinity are dimensionless and the units attribute should normally be given as 1e-3 or 0.001 i.e. parts per thousand. Sea surface salinity is often abbreviated as "SSS". For the salinity of sea water at a particular depth or layer, a data variable of "sea_water_salinity" or one of the more precisely defined salinities should be used with a vertical coordinate axis. There are standard names for the precisely defined salinity quantities: sea_water_knudsen_salinity, S_K (used for salinity observations between 1901 and 1966), sea_water_cox_salinity, S_C (used for salinity observations between 1967 and 1977), sea_water_practical_salinity, S_P (used for salinity observations from 1978 to the present day), sea_water_absolute_salinity, S_A, sea_water_preformed_salinity, S_*, and sea_water_reference_salinity. Practical Salinity is reported on the Practical Salinity Scale of 1978 (PSS-78), and is usually based on the electrical conductivity of sea water in observations since the 1960s. Conversion of data between the observed scales follows: S_P = (S_K - 0.03) * (1.80655 / 1.805) and S_P = S_C, however the accuracy of the latter is dependent on whether chlorinity or conductivity was used to determine the S_C value, with this inconsistency driving the development of PSS-78. The more precise standard names should be used where appropriate for both modelled and observed salinities. In particular, the use of sea_water_salinity to describe salinity observations made from 1978 onwards is now deprecated in favor of the term sea_water_practical_salinity which is the salinity quantity stored by national data centers for post-1978 observations. The only exception to this is where the observed salinities are definitely known not to be recorded on the Practical Salinity Scale. The unit "parts per thousand" was used for sea_water_knudsen_salinity and sea_water_cox_salinity. I CFSN0553 litter_carbon_flux "Litter carbon" is dead inorganic material in or above the soil quantified as the mass of carbon which it contains. The litter carbon flux is the rate of production of litter. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. D MGOP5BFS mass_flux_of_carbon_into_litter_from_vegetation 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. It is distinct from coarse wood debris. The precise distinction between "fine" and "coarse" is model dependent. The sum of the quantities with standard names mass_flux_of_carbon_into_litter_from_vegetation_due_to_mortality and mass_flux_of_carbon_into_litter_from_vegetation_due_to_senescence is mass_flux_of_carbon_into_litter_from_vegetation. I CFV9S1 eastward_transformed_eulerian_mean_air_velocity "Eastward" indicates a vector component which is positive when directed eastward (negative westward). The "Transformed Eulerian Mean" refers to a formulation of the mean equations which incorporates some eddy terms into the definition of the mean, described in Andrews et al (1987): Middle Atmospheric Dynamics. Academic Press. M 391VFPF4 atmosphere_mass_content_of_convective_cloud_ice "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. Convective cloud is that produced by the convection schemes in an atmosphere model. I S1CHM4XM effective_radius_of_convective_cloud_liquid_water_particle_at_convective_liquid_water_cloud_top The effective radius of a size distribution of particles, such as aerosols, cloud droplets or ice crystals, is the area weighted mean radius of particle size. It is calculated as the ratio of the third to the second moment of the particle size distribution. The phrase "convective_liquid_water_cloud_top" refers to the top of the highest convective liquid water cloud. Convective cloud is that produced by the convection schemes in an atmosphere model. I CFV16A13 fast_soil_pool_carbon_content "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. "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. "Fast soil pool" refers to the decay of organic matter in soil with a characteristic period of less than ten years under reference climate conditions of a temperature of 20 degrees Celsius and no water limitations. D AT7HOKCE fast_soil_pool_mass_content_of_carbon "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. 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. "Fast soil pool" refers to the decay of organic matter in soil with a characteristic period of less than ten years under reference climate conditions of a temperature of 20 degrees Celsius and no water limitations. I CFV16A52 surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_emission_from_crop_harvesting 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. "Emission" means emission from a primary source located anywhere within the atmosphere, including at the lower boundary (i.e. earth's surface). "Emission" is a process entirely distinct from "re-emission" which is used in some standard names. The definition of "crop" is model dependent, for example, some models may include fruit trees, trees grown for timber or other types of agricultural and forestry planting as crops. Crop harvesting means the human activity of collecting plant materials for the purpose of turning them into forestry or agricultural products. M CFV16A19 medium_soil_pool_carbon_content "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. "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. "Medium soil pool" refers to the decay of organic matter in soil with a characteristic period of between ten and one hundred years under reference climate conditions of a temperature of 20 degrees Celsius and no water limitations. D LZJ8947A medium_soil_pool_mass_content_of_carbon "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. 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. "Medium soil pool" refers to the decay of organic matter in soil with a characteristic period of between ten and one hundred years under reference climate conditions of a temperature of 20 degrees Celsius and no water limitations. I INRMMT8S surface_upward_mass_flux_of_carbon_dioxide_expressed_as_carbon_due_to_plant_respiration_in_leaves 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 chemical formula for carbon dioxide is CO2. 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. 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. I