Update for CF Version:38

The surface called "surface" means the lower boundary of the atmosphere. "Upward" indicates a vector component which is positive when directed upward (negative downward). In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. The phrase "expressed_as" is used in the construction A_expressed_as_B, where B is a chemical constituent of A. It means that the quantity indicated by the standard name is calculated solely with respect to the B contained in A, neglecting all other chemical constituents of A. The chemical formula for carbon dioxide is CO2. The specification of a physical process by the phrase "due_to_" process means that the quantity named is a single term in a sum of terms which together compose the general quantity named by omitting the phrase. "Anthropogenic" means influenced, caused, or created by human activity. "Anthropogenic land use change" means human changes to land, excluding forest regrowth. It 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.

The surface called "surface" means the lower boundary of the atmosphere. "Upward" indicates a vector component which is positive when directed upward (negative downward). The vertical heat flux in air is the sum of all heat fluxes i.e. radiative, latent and sensible. 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. "Anthropogenic" means influenced, caused, or created by human activity. The heat flux due to anthropogenic energy consumption results from non-renewable human primary energy consumption, including energy use by vehicles, commercial and residential buildings, industry, and power plants. Primary energy refers to energy in natural resources, fossil and non-fossil, before conversion into other forms, such as electricity.

"Water" means water in all phases. "Content" indicates a quantity per unit area. The mass content of water in soil 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.

"tendency_of_X" means derivative of X with respect to time. 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. "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 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. 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.

"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.

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. 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.

The "gross rate of decrease in area fraction" is the fraction of a grid cell that transitions from a given area type per unit time, for example, as a result of land use changes. The quantity described by this standard name is a gross decrease because it includes only land where the use transitions away from the given area type and excludes land that transitions to that area type during the same period. The area type should be specified using a coordinate of scalar coordinate variable with standard name area_type. There is also a standard name for gross_rate_of_increase_in_area_fraction.

"Downward" indicates a vector component which is positive when directed downward (negative upward). The surface called "surface" means the lower boundary of the atmosphere. 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. "Irrigation" includes water used to sustain crops, trees, pastures and urban lawns.

The "rate of increase in area fraction" is the fraction of a grid cell that transitions to a given area type per unit time, for example, as a result of land use changes. The quantity described by this standard name is a gross increase because it includes only land where the use transitions to the given area type and excludes land that transitions away from that area type during the same period. The area type should be specified using a coordinate or scalar coordinate variable with standard name area_type. There is also a standard name for gross_rate_of_decrease_in_area_fraction.

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. "Anthropogenic" means influenced, caused, or created by human activity. 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. "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.

"Content" indicates a quantity per unit area. "Water" means water in all phases. "Layer" means any layer with upper and lower boundaries that have constant values in some vertical coordinate. There must be a vertical coordinate variable indicating the extent of the layer(s). If the layers are model layers, the vertical coordinate can be "model_level_number", but it is recommended to specify a physical coordinate (in a scalar or auxiliary coordinate variable) as well. Quantities defined for a soil layer must have a vertical coordinate variable with boundaries indicating the extent of the layer(s).

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 phosphorus" means phosphate ions in solution.