Update for CF Version:77
change_over_time_in_surface_snow_amount
Unit: kg m-2
Unit ref: KMP2
The phrase "change_over_time_in_X" means change in a quantity X over a time-interval, which should be defined by the bounds of the time coordinate. "Amount" means mass per unit area. Surface snow amount refers to the amount on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
surface_snow_melt_heat_flux
Unit: W m-2
Unit ref: UFAA
Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. The snow melt heat flux is the supply of latent heat which is melting snow at freezing point. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics.
surface_snow_area_fraction
Unit: 1
Unit ref: UUUU
AMIP: snc
"Area fraction" is the fraction of a grid cell's horizontal area that has some characteristic of interest. It is evaluated as the area of interest divided by the grid cell area. It may be expressed as a fraction, a percentage, or any other dimensionless representation of a fraction. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
surface_snow_and_ice_melt_heat_flux
Unit: W m-2
Unit ref: UFAA
The snow and ice melt heat flux is the supply of latent heat which is melting snow and ice at freezing point. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics.
tendency_of_surface_snow_amount
Unit: kg m-2 s-1
Unit ref: KSP2
The phrase "tendency_of_X" means derivative of X with respect to time. "Amount" means mass per unit area. Surface snow amount refers to the amount on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
surface_roughness_length_for_heat_in_air
Unit: m
Unit ref: ULAA
The height above the surface where the mean value of heat assumes its surface value when extrapolated along a logarithmic profile downward towards the surface. The surface called "surface" means the lower boundary of the atmosphere.
integral_wrt_time_of_surface_downward_eastward_stress
Unit: Pa s
Unit ref: PASS
The phrase "integral_wrt_X_of_Y" means int Y dX. The data variable should have an axis for X specifying the limits of the integral as bounds. The abbreviation "wrt" means "with respect to". The surface called "surface" means the lower boundary of the atmosphere. "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents. "Downward" indicates a vector component which is positive when directed downward (negative upward). "Eastward" indicates a vector component which is positive when directed eastward (negative westward). "Downward eastward" indicates the ZX component of a tensor. A downward eastward stress is a downward flux of eastward momentum, which accelerates the lower medium eastward and the upper medium westward.
surface_snow_density
Unit: kg m-3
Unit ref: UKMC
Snow density is the density of the snow cover. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. The density of a substance is its mass per unit volume.
shallow_convective_cloud_base_altitude
Unit: m
Unit ref: ULAA
The phrase "cloud_base" refers to the base of the lowest cloud. Altitude is the (geometric) height above the geoid, which is the reference geopotential surface. The geoid is similar to mean sea level. Shallow convective cloud is nonprecipitating cumulus cloud with a cloud top below 3000m above the surface produced by the convection schemes in an atmosphere model. Some atmosphere models differentiate between shallow and deep convection.
surface_roughness_length_for_humidity_in_air
Unit: m
Unit ref: ULAA
The height above the surface where the mean value of humidity assumes its surface value when extrapolated along a logarithmic profile downward towards the surface. The surface called "surface" means the lower boundary of the atmosphere.
surface_snow_amount
Unit: kg m-2
Unit ref: KMP2
AMIP: snw
GRIB: 65
"Amount" means mass per unit area. Surface snow amount refers to the amount on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
surface_snow_and_ice_refreezing_flux
Unit: kg m-2 s-1
Unit ref: KSP2
"Surface snow and ice refreezing flux" means the mass flux of surface meltwater which refreezes within the snow or firn. The surface called "surface" means the lower boundary of the atmosphere. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics.
mass_fraction_of_solid_precipitation_falling_onto_surface_snow
Unit: 1
Unit ref: UUUU
The quantity with standard name mass_fraction_of_solid_precipitation_falling_onto_surface_snow is the mass of solid precipitation falling onto snow as a fraction of the mass of solid precipitation falling within the area of interest. Solid precipitation refers to the precipitation of water in the solid phase. Water in the atmosphere exists in one of three phases: solid, liquid or vapor. The solid phase can exist as snow, hail, graupel, cloud ice, or as a component of aerosol. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. Unless indicated in the cell_methods attribute, a quantity is assumed to apply to the whole area of each horizontal grid box.
surface_downward_eastward_stress_due_to_boundary_layer_mixing
Unit: Pa
Unit ref: PASX
The surface called "surface" means the lower boundary of the atmosphere. "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents. "Downward" indicates a vector component which is positive when directed downward (negative upward). "Eastward" indicates a vector component which is positive when directed eastward (negative westward). "Downward eastward" indicates the ZX component of a tensor. A downward eastward stress is a downward flux of eastward momentum, which accelerates the lower medium eastward and the upper medium westward. 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. "Boundary layer mixing" means turbulent motions that transport heat, water, momentum and chemical constituents within the atmospheric boundary layer and affect exchanges between the surface and the atmosphere. The atmospheric boundary layer is typically characterised by a well-mixed sub-cloud layer of order 500 metres, and by a more extended conditionally unstable layer with boundary-layer clouds up to 2 km. (Reference: IPCC Third Assessment Report, Working Group 1: The Scientific Basis, 7.2.2.3, https://archive.ipcc.ch/ipccreports/tar/wg1/273.htm).
shallow_convective_cloud_top_altitude
Unit: m
Unit ref: ULAA
The phrase "cloud_top" refers to the top of the highest cloud. Altitude is the (geometric) height above the geoid, which is the reference geopotential surface. The geoid is similar to mean sea level. Shallow convective cloud is nonprecipitating cumulus cloud with a cloud top below 3000m above the surface produced by the convection schemes in an atmosphere model. Some atmosphere models differentiate between shallow and deep convection.
tendency_of_mass_fraction_of_convective_cloud_ice_in_air
Unit: s-1
Unit ref: PRSC
The phrase "tendency_of_X" means derivative of X with respect to time. "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 or biological group denoted by X may be described by a single term such as "nitrogen" or a phrase such as "nox_expressed_as_nitrogen". Convective cloud is that produced by the convection schemes in an atmosphere model.
tendency_of_mass_fraction_of_convective_cloud_liquid_water_in_air
Unit: s-1
Unit ref: PRSC
The phrase "tendency_of_X" means derivative of X with respect to time. "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 or biological group denoted by X may be described by a single term such as "nitrogen" or a phrase such as "nox_expressed_as_nitrogen". Convective cloud is that produced by the convection schemes in an atmosphere model. "Cloud liquid water" refers to the liquid phase of cloud water. A diameter of 0.2 mm has been suggested as an upper limit to the size of drops that shall be regarded as cloud drops; larger drops fall rapidly enough so that only very strong updrafts can sustain them. Any such division is somewhat arbitrary, and active cumulus clouds sometimes contain cloud drops much larger than this. Reference: AMS Glossary http://glossary.ametsoc.org/wiki/Cloud_drop.
surface_snow_binary_mask
Unit: 1
Unit ref: UUUU
X"_binary_mask" has 1 where condition X is met, 0 elsewhere. The value is 1 where the snow cover area fraction is greater than a threshold, and 0 elsewhere. The threshold must be specified by associating a coordinate variable or scalar coordinate variable with the data variable and giving the coordinate variable a standard name of surface_snow_area_fraction. The values of the coordinate variable are the threshold values for the corresponding subarrays of the data variable. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
liquid_water_mass_flux_into_soil_due_to_surface_snow_melt
Unit: kg m-2 s-1
Unit ref: KSP2
In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. 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.
tendency_of_surface_snow_amount_due_to_sea_ice_dynamics
Unit: kg m-2 s-1
Unit ref: KSP2
The quantity with standard name tendency_of_surface_snow_amount_due_to_sea_ice_dynamics is the rate of change of snow amount caused by advection of the sea ice upon which the snow is lying. The phrase "tendency_of_X" means derivative of X with respect to time. "Amount" means mass per unit area. Surface snow amount refers to the amount on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. 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. "Sea ice dynamics" refers to advection of sea ice. "Sea ice" means all ice floating in the sea which has formed from freezing sea water, rather than by other processes such as calving of land ice to form icebergs.
eastward_air_velocity_relative_to_sea_water
Unit: m s-1
Unit ref: UVAA
The eastward motion of air, relative to near-surface eastward current; calculated as eastward_wind minus eastward_sea_water_velocity. A vertical coordinate variable or scalar coordinate with standard name "depth" should be used to indicate the depth of sea water velocity used in the calculation. Similarly, a vertical coordinate variable or scalar coordinate with standard name "height" should be used to indicate the height of the the wind component. A velocity is a vector quantity. "Eastward" indicates a vector component which is positive when directed eastward (negative westward).
tendency_of_thermal_energy_content_of_surface_snow_due_to_rainfall_temperature_excess_above_freezing
Unit: W m-2
Unit ref: UFAA
The phrase "tendency_of_X" means derivative of X with respect to time. "Content" indicates a quantity per unit area. Thermal energy is the total vibrational energy, kinetic and potential, of all the molecules and atoms in a substance. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. The quantity with standard name tendency_of_thermal_energy_content_of_surface_snow_due_to_rainfall_temperature_excess_above_freezing is the heat energy carried by rainfall reaching the surface. It is calculated relative to the heat that would be carried by rainfall reaching the surface at zero degrees Celsius. It is calculated as the product QrainCpTrain, where Qrain is the mass flux of rainfall reaching the surface (kg m-2 s-1), Cp is the specific heat capacity of water and Train is the temperature in degrees Celsius of the rain water reaching the surface. 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.
temperature_in_surface_snow
Unit: K
Unit ref: UPKA
GRIB: E238
"Temperature in surface snow" is the bulk temperature of the snow, not the surface (skin) temperature. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
thermal_energy_content_of_surface_snow
Unit: J m-2
Unit ref: JMSQ
"Content" indicates a quantity per unit area. Thermal energy is the total vibrational energy, kinetic and potential, of all the molecules and atoms in a substance. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
northward_air_velocity_relative_to_sea_water
Unit: m s-1
Unit ref: UVAA
The northward motion of air, relative to near-surface northward current; calculated as northward_wind minus northward_sea_water_velocity. A vertical coordinate variable or scalar coordinate with standard name "depth" should be used to indicate the depth of sea water velocity used in the calculation. Similarly, a vertical coordinate variable or scalar coordinate with standard name "height" should be used to indicate the height of the the wind component. A velocity is a vector quantity. "Northward" indicates a vector component which is positive when directed northward (negative southward).
to_direction_of_surface_downward_stress
Unit: degree
Unit ref: UAAA
The phrase "to_direction" is used in the construction X_to_direction and indicates the direction towards which the vector of X is headed. The direction is a bearing in the usual geographical sense, measured positive clockwise from due north. The surface called "surface" means the lower boundary of the atmosphere. "Downward" indicates a vector component which is positive when directed downward (negative upward). "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents.
surface_downward_northward_stress
Unit: Pa
Unit ref: PASX
AMIP: tauv
GRIB: E181
The surface called "surface" means the lower boundary of the atmosphere. "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents. "Downward" indicates a vector component which is positive when directed downward (negative upward). "Northward" indicates a vector component which is positive when directed northward (negative southward). "Downward northward" indicates the ZY component of a tensor. A downward northward stress is a downward flux of northward momentum, which accelerates the lower medium northward and the upper medium southward.
tendency_of_atmosphere_mass_content_of_water_vapor_due_to_sublimation_of_surface_snow_and_ice
Unit: kg m-2 s-1
Unit ref: KSP2
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. Atmosphere water vapor content is sometimes referred to as "precipitable water", although this term does not imply the water could all be precipitated. 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. Sublimation is the conversion of solid into vapor. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. Unless indicated in the cell_methods attribute, a quantity is assumed to apply to the whole area of each horizontal grid box.
surface_downward_x_stress_correction
Unit: Pa
Unit ref: PASX
The surface called "surface" means the lower boundary of the atmosphere. "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents. "Downward" indicates a vector component which is positive when directed downward (negative upward). "x" indicates a vector component along the grid x-axis, positive with increasing x. "Downward x" indicates the ZX component of a tensor. A downward x stress is a downward flux of momentum, which accelerates the lower medium in the direction of increasing x and and the upper medium in the direction of decreasing x. A positive correction is downward i.e. added to the ocean.
magnitude_of_surface_downward_stress
Unit: Pa
Unit ref: PASX
The phrase "magnitude_of_X" means magnitude of a vector X. The surface called "surface" means the lower boundary of the atmosphere. "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents. "Downward" indicates a vector component which is positive when directed downward (negative upward).
mass_concentration_of_microphytoplankton_expressed_as_chlorophyll_in_sea_water
Unit: kg m-3
Unit ref: UKMC
Mass concentration means mass per unit volume and is used in the construction mass_concentration_of_X_in_Y, where X is a material constituent of Y. A chemical or biological species denoted by X may be described by a single term such as "nitrogen" or a phrase such as "nox_expressed_as_nitrogen". The 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. Chlorophylls are the green pigments found in most plants, algae and cyanobacteria; their presence is essential for photosynthesis to take place. There are several different forms of chlorophyll that occur naturally. All contain a chlorin ring (chemical formula C20H16N4) which gives the green pigment and a side chain whose structure varies. The naturally occurring forms of chlorophyll contain between 35 and 55 carbon atoms. Microphytoplankton are phytoplankton between 20 and 200 micrometers in size. Phytoplankton are algae that grow where there is sufficient light to support photosynthesis.
surface_roughness_length_for_momentum_in_air
Unit: m
Unit ref: ULAA
The height above the displacement plane at which the mean wind becomes zero when extrapolating the logarithmic wind speed profile downward through the surface layer. The surface called "surface" means the lower boundary of the atmosphere.
tendency_of_atmosphere_mass_content_of_water_vapor_due_to_sublimation_of_surface_snow
Unit: kg m-2 s-1
Unit ref: KSP2
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. Atmosphere water vapor content is sometimes referred to as "precipitable water", although this term does not imply the water could all be precipitated. 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. Sublimation is the conversion of solid into vapor. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. Unless indicated in the cell_methods attribute, a quantity is assumed to apply to the whole area of each horizontal grid box.
surface_snow_sublimation_amount
Unit: kg m-2
Unit ref: KMP2
Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. "Amount" means mass per unit area. Sublimation is the conversion of solid into vapor.
mass_fraction_of_rainfall_falling_onto_surface_snow
Unit: 1
Unit ref: UUUU
The quantity with standard name mass_fraction_of_rainfall_falling_onto_surface_snow is the mass of rainfall falling onto snow as a fraction of the mass of rainfall falling within the area of interest. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. The surface called "surface" means the lower boundary of the atmosphere. Unless indicated in the cell_methods attribute, a quantity is assumed to apply to the whole area of each horizontal grid box.
surface_snow_melt_and_sublimation_heat_flux
Unit: W m-2
Unit ref: UFAA
Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. Sublimation is the conversion of solid into vapor. The snow melt and sublimation heat flux is the supply of latent heat which is converting snow to liquid water (melting) and water vapor (sublimation). In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics.
surface_snow_sublimation_heat_flux
Unit: W m-2
Unit ref: UFAA
Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. Sublimation is the conversion of solid into vapor. The snow sublimation heat flux is the supply of latent heat which is causing evaporation of snow to water vapor. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics.
lwe_thickness_of_surface_snow_amount
Unit: m
Unit ref: ULAA
GRIB: E141
The abbreviation "lwe" means liquid water equivalent. "Amount" means mass per unit area. The construction lwe_thickness_of_X_amount or _content means the vertical extent of a layer of liquid water having the same mass per unit area. Surface snow amount refers to the amount on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
surface_snow_thickness
Unit: m
Unit ref: ULAA
AMIP: snd
GRIB: 66
Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. "Thickness" means the vertical extent of a layer. Unless indicated in the cell_methods attribute, a quantity is assumed to apply to the whole area of each horizontal grid box. Previously, the qualifier where_type was used to specify that the quantity applies only to the part of the grid box of the named type. Names containing the where_type qualifier are deprecated and newly created data should use the cell_methods attribute to indicate the horizontal area to which the quantity applies.
surface_snow_melt_amount
Unit: kg m-2
Unit ref: KMP2
GRIB: 99
Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. The surface called "surface" means the lower boundary of the atmosphere. "Amount" means mass per unit area.
soot_content_of_surface_snow
Unit: kg m-2
Unit ref: KMP2
"Content" indicates a quantity per unit area. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
magnitude_of_air_velocity_relative_to_sea_water
Unit: m s-1
Unit ref: UVAA
The quantity with standard name magnitude_of_air_velocity_relative_to_sea_water is the speed of the motion of the air relative to the near-surface current, usually derived from vectors. The components of the relative velocity vector have standard names eastward_air_velocity_relative_to_sea_water and northward_air_velocity_relative_to_sea_water. A vertical coordinate variable or scalar coordinate variable with standard name "depth" should be used to indicate the depth of sea water velocity used in the calculation. Similarly, a vertical coordinate variable or scalar coordinate with standard name "height" should be used to indicate the height of the the wind component.
surface_downward_y_stress
Unit: Pa
Unit ref: PASX
The surface called "surface" means the lower boundary of the atmosphere. "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents. "Downward" indicates a vector component which is positive when directed downward (negative upward). "y" indicates a vector component along the grid y-axis, positive with increasing y. "Downward y" indicates the ZY component of a tensor. A downward y stress is a downward flux of momentum, which accelerates the lower medium in the direction of increasing y and and the upper medium in the direction of decreasing y.
stratiform_graupel_fall_amount
Unit: kg m-2
Unit ref: KMP2
Stratiform precipitation, whether liquid or frozen, is precipitation that formed in stratiform cloud. Graupel consists of heavily rimed snow particles, often called snow pellets; often indistinguishable from very small soft hail except when the size convention that hail must have a diameter greater than 5 mm is adopted. Reference: American Meteorological Society Glossary http://glossary.ametsoc.org/wiki/Graupel. There are also separate standard names for hail. Standard names for "graupel_and_hail" should be used to describe data produced by models that do not distinguish between hail and graupel. "Amount" means mass per unit area.
surface_snow_and_ice_melt_flux
Unit: kg m-2 s-1
Unit ref: KSP2
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. "Surface snow and ice melt flux" means the mass flux of all melting at the surface. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
surface_downward_eastward_stress
Unit: Pa
Unit ref: PASX
AMIP: tauu
GRIB: E180
The surface called "surface" means the lower boundary of the atmosphere. "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents. "Downward" indicates a vector component which is positive when directed downward (negative upward). "Eastward" indicates a vector component which is positive when directed eastward (negative westward). "Downward eastward" indicates the ZX component of a tensor. A downward eastward stress is a downward flux of eastward momentum, which accelerates the lower medium eastward and the upper medium westward.
to_direction_of_air_velocity_relative_to_sea_water
Unit: degree
Unit ref: UAAA
The quantity with standard name to_direction_of_air_velocity_relative_to_sea_water is the difference between the direction of motion of the air and the near-surface current. The phrase "to_direction" is used in the construction X_to_direction and indicates the direction towards which the velocity vector of X is headed. The direction is a bearing in the usual geographical sense, measured positive clockwise from due north. The components of the relative velocity vector have standard names eastward_air_velocity_relative_to_sea_water and northward_air_velocity_relative_to_sea_water. A vertical coordinate variable or scalar coordinate variable with standard name "depth" should be used to indicate the depth of sea water velocity used in the calculation. Similarly, a vertical coordinate variable or scalar coordinate with standard name "height" should be used to indicate the height of the the wind component.
sea_ice_and_surface_snow_amount
Unit: kg m-2
Unit ref: KMP2
"Amount" means mass per unit area. Surface snow amount refers to the amount on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. "Sea ice" means all ice floating in the sea which has formed from freezing sea water, rather than by other processes such as calving of land ice to form icebergs.
mass_fraction_of_shallow_convective_cloud_liquid_water_in_air
Unit: 1
Unit ref: UUUU
"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 or biological group denoted by X may be described by a single term such as "nitrogen" or a phrase such as "nox_expressed_as_nitrogen". Shallow convective cloud is nonprecipitating cumulus cloud with a cloud top below 3000m above the surface produced by the convection schemes in an atmosphere model. Some atmosphere models differentiate between shallow and deep convection. "Cloud liquid water" refers to the liquid phase of cloud water. A diameter of 0.2 mm has been suggested as an upper limit to the size of drops that shall be regarded as cloud drops; larger drops fall rapidly enough so that only very strong updrafts can sustain them. Any such division is somewhat arbitrary, and active cumulus clouds sometimes contain cloud drops much larger than this. Reference: AMS Glossary http://glossary.ametsoc.org/wiki/Cloud_drop.
tendency_of_surface_snow_amount_due_to_drifting_into_sea
Unit: kg m-2 s-1
Unit ref: KSP2
The phrase "tendency_of_X" means derivative of X with respect to time. "Amount" means mass per unit area. Surface snow amount refers to the amount on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. 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.
tendency_of_surface_snow_amount_due_to_conversion_of_snow_to_sea_ice
Unit: kg m-2 s-1
Unit ref: KSP2
The phrase "tendency_of_X" means derivative of X with respect to time. "Amount" means mass per unit area. Surface snow amount refers to the amount on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. 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. "Conversion of snow to sea ice" occurs when the mass of snow accumulated on an area of sea ice is sufficient to cause the ice to become mostly submerged. Waves can then wash over the ice and snow surface and freeze into a layer that becomes "snow ice". "Sea ice" means all ice floating in the sea which has formed from freezing sea water, rather than by other processes such as calving of land ice to form icebergs.
age_of_surface_snow
Unit: day
Unit ref: UTAA
"Age of surface snow" means the length of time elapsed since the snow accumulated on the earth's surface. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
surface_downward_x_stress
Unit: Pa
Unit ref: PASX
The surface called "surface" means the lower boundary of the atmosphere. "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents. "Downward" indicates a vector component which is positive when directed downward (negative upward). "x" indicates a vector component along the grid x-axis, positive with increasing x. "Downward x" indicates the ZX component of a tensor. A downward x stress is a downward flux of momentum, which accelerates the lower medium in the direction of increasing x and and the upper medium in the direction of decreasing x.
surface_downward_northward_stress_due_to_boundary_layer_mixing
Unit: Pa
Unit ref: PASX
The surface called "surface" means the lower boundary of the atmosphere. "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents. "Downward" indicates a vector component which is positive when directed downward (negative upward). "Northward" indicates a vector component which is positive when directed northward (negative southward). "Downward northward" indicates the ZY component of a tensor. A downward northward stress is a downward flux of northward momentum, which accelerates the lower medium northward and the upper medium southward. 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. "Boundary layer mixing" means turbulent motions that transport heat, water, momentum and chemical constituents within the atmospheric boundary layer and affect exchanges between the surface and the atmosphere. The atmospheric boundary layer is typically characterised by a well-mixed sub-cloud layer of order 500 metres, and by a more extended conditionally unstable layer with boundary-layer clouds up to 2 km. (Reference: IPCC Third Assessment Report, Working Group 1: The Scientific Basis, 7.2.2.3, https://archive.ipcc.ch/ipccreports/tar/wg1/273.htm).
surface_snow_melt_flux
Unit: kg m-2 s-1
Unit ref: KSP2
AMIP: snm
Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants. 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.
surface_downward_y_stress_correction
Unit: Pa
Unit ref: PASX
The surface called "surface" means the lower boundary of the atmosphere. "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents. "Downward" indicates a vector component which is positive when directed downward (negative upward). "y" indicates a vector component along the grid y-axis, positive with increasing y. "Downward y" indicates the ZY component of a tensor. A downward y stress is a downward flux of momentum, which accelerates the lower medium in the direction of increasing y and and the upper medium in the direction of decreasing y. A positive correction is downward i.e. added to the ocean.
liquid_water_content_of_surface_snow
Unit: kg m-2
Unit ref: KMP2
"Content" indicates a quantity per unit area. Surface snow refers to the snow on the solid ground or on surface ice cover, but excludes, for example, falling snowflakes and snow on plants.
integral_wrt_time_of_surface_downward_northward_stress
Unit: Pa s
Unit ref: PASS
The phrase "integral_wrt_X_of_Y" means int Y dX. The data variable should have an axis for X specifying the limits of the integral as bounds. The abbreviation "wrt" means "with respect to". The surface called "surface" means the lower boundary of the atmosphere. "Surface stress" means the shear stress (force per unit area) exerted by the wind at the surface. A downward stress is a downward flux of momentum. Over large bodies of water, wind stress can drive near-surface currents. "Downward" indicates a vector component which is positive when directed downward (negative upward). "Northward" indicates a vector component which is positive when directed northward (negative southward). "Downward northward" indicates the ZY component of a tensor. A downward northward stress is a downward flux of northward momentum, which accelerates the lower medium northward and the upper medium southward.
mass_concentration_of_nanophytoplankton_expressed_as_chlorophyll_in_sea_water
Unit: kg m-3
Unit ref: UKMC
Mass concentration means mass per unit volume and is used in the construction mass_concentration_of_X_in_Y, where X is a material constituent of Y. A chemical or biological species denoted by X may be described by a single term such as "nitrogen" or a phrase such as "nox_expressed_as_nitrogen". The 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. Chlorophylls are the green pigments found in most plants, algae and cyanobacteria; their presence is essential for photosynthesis to take place. There are several different forms of chlorophyll that occur naturally. All contain a chlorin ring (chemical formula C20H16N4) which gives the green pigment and a side chain whose structure varies. The naturally occurring forms of chlorophyll contain between 35 and 55 carbon atoms. Nanophytoplankton are phytoplankton between 2 and 20 micrometers in size. Phytoplankton are algae that grow where there is sufficient light to support photosynthesis.