Proposals for CF

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118 proposals match your search

rate_of_global_mean_sea_level_change

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329
Units: m year-1 (MPYR)
Term change from Term: tendency_of_global_average_sea_level_change
Global average sea level change is due to change in volume of the water in the ocean, caused by mass and/or density change, or to change in the volume of the ocean basins, caused by tectonics etc. It is sometimes called "eustatic", which is a term that also has other definitions. It differs from the change in the global average sea surface height relative to the centre of the Earth by the global average vertical movement of the ocean floor. Zero sea level change is an arbitrary level. "tendency_of_X" means derivative of X with respect to time. Because global average sea level change quantifies the change in volume of the world ocean, it is not calculated necessarily by considering local changes in mean sea level.

amplitude_of_global_mean_sea_level_change

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329
Units: m (ULAA)
Term change from Term: amplitude_of_global_average_sea_level_change
Global average sea level change is due to change in volume of the water in the ocean, caused by mass and/or density change, or to change in the volume of the ocean basins, caused by tectonics etc. It is sometimes called "eustatic", which is a term that also has other definitions. It differs from the change in the global average sea surface height relative to the centre of the Earth by the global average vertical movement of the ocean floor. Zero sea level change is an arbitrary level. Amplitude is the magnitude of a wave modelled by a sinusoidal function. A coordinate variable of harmonic_period should be used to specify the period of the sinusoidal wave. Because global average sea level change quantifies the change in volume of the world ocean, it is not calculated necessarily by considering local changes in mean sea level.

change in_sea_surface_height_due_to_change_in_air_pressure_and_wind_at_high_frequency

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329
Units: m (ULAA)
Term change from Term: sea_surface_height_correction_due_to_air_pressure_and_wind_at_high_frequency
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. "Air pressure and wind at high frequency" means variations in air pressure with periods shorter than 20 days. These give rise to corresponding variations in sea surface topography. The quantity sea_surface_height_correction_due_to_air_pressure_and_wind_at_high_frequency should be applied by adding it to the quantity with standard name altimeter_range. Additional altimeter range corrections are given by the quantities with standard names altimeter_range_correction_due_to_wet_troposphere, altimeter_range_correction_due_to_dry_troposphere, altimeter_range_correction_due_to_ionosphere and sea_surface_height_correction_due_to_air_pressure_at_low_frequency.

change_in_sea_surface_height_due_to_change_in_air_pressure_at_low_frequency

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329
Units: m (ULAA)
Term change from Term: sea_surface_height_correction_due_to_air_pressure_at_low_frequency
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. "Air pressure at low frequency" means variations in air pressure with periods longer than 20 days. These give rise to corresponding variations in sea surface topography. The quantity sea_surface_height_correction_due_to_air_pressure_at_low_frequency is commonly called the "inverted barometer effect" and the correction should be applied by adding it to the quantity with standard name altimeter_range. Additional altimeter range corrections are given by the quantities with standard names altimeter_range_correction_due_to_wet_troposphere, altimeter_range_correction_due_to_dry_troposphere, altimeter_range_correction_due_to_ionosphere and sea_surface_height_correction_due_to_air_pressure_and_wind_at_high_frequency.

global_mean_thermosteric_sea_level_change

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329
Units: m (ULAA)
Term change from Term: global_average_thermosteric_sea_level_change
Global average thermosteric sea level change is the part caused by change in density due to change in temperature i.e. thermal expansion. This in turn results in a change in volume of the world ocean. Zero sea level change is an arbitrary level. Because global average sea level change quantifies the change in volume of the world ocean, it is not calculated necessarily by considering local changes in mean sea level.

global_mean_sea_level_change

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329
Units: m (ULAA)
Term change from Term: global_average_sea_level_change
Global average sea level change is due to change in volume of the water in the ocean, caused by mass and/or density change, or to change in the volume of the ocean basins, caused by tectonics etc. It is sometimes called "eustatic", which is a term that also has other definitions. It differs from the change in the global average sea surface height relative to the centre of the Earth by the global average vertical movement of the ocean floor. Zero sea level change is an arbitrary level. Because global average sea level change quantifies the change in volume of the world ocean, it is not calculated necessarily by considering local changes in mean sea level.

global_mean_steric_sea_level_change

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329
Units: m (ULAA)
Term change from Term: global_average_steric_sea_level_change
Global average steric sea level change is caused by changes in sea water density due to changes in temperature (thermosteric) and salinity (halosteric). This in turn results in a change in volume of the world ocean. Zero sea level change is an arbitrary level. Because global average sea level change quantifies the change in volume of the world ocean, it is not calculated necessarily by considering local changes in mean sea level.

phase_of_global_mean_sea_level_change

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329
Units: degree (UAAA)
Term change from Term: phase_of_global_average_sea_level_change
Global average sea level change is due to change in volume of the water in the ocean, caused by mass and/or density change, or to change in the volume of the ocean basins, caused by tectonics etc. It is sometimes called "eustatic", which is a term that also has other definitions. It differs from the change in the global average sea surface height relative to the centre of the Earth by the global average vertical movement of the ocean floor. Zero sea level change is an arbitrary level. Phase is the initial angle of a wave modelled by a sinusoidal function. A coordinate variable of harmonic_period should be used to specify the period of the sinusoidal wave. Because global average sea level change quantifies the change in volume of the world ocean, it is not calculated necessarily by considering local changes in mean sea level.

change_in_mean_sea_level_due_to_change_in_air_pressure

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329

change_in_mean_sea_level_wrt_reference_ellipsoid

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329

change_in_mean_sea_level_due_to_change_in_geoid_and_solid_earth_deformation

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329

manometric_change_in_sea_surface_height

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329

manometric_change_in_mean_sea_level

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329

change_in_ocean_dynamic_sea_level

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329

mean_sea_level_height_above_reference_ellipsoid

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329

change_in_height_of_solid_surface_wrt_reference_ellipsoid

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329

sterodynamic_change_in_sea_level

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329

change_in_mean_sea_level_due_to_change_in_global_ocean_mass_and_geoid_and_solid_earth_deformation

under discussion
Proposer: Jonathan Gregory
Proposed Date: 26 Jun 2024
Comments: #329

surface_upwelling_longwave_flux_in_air_assuming_clear_sky_and_reference_mole_fraction_of_ozone_in_air

accepted
Proposer: Fiona O'Connor
Proposed Date: 3 Jul 2024
Comments: #332, #299
Units: W/m2 (UFAA)
New Term
The surface called "surface" means the lower boundary of the atmosphere. The term "longwave" means longwave radiation. Upwelling radiation is radiation from below. It does not mean "net upward". The sign convention is that "upwelling" is positive upwards and "downwelling" is positive downwards. When thought of as being incident on a surface, a radiative flux is sometimes called "irradiance". In addition, it is identical with the quantity measured by a cosine-collector light-meter and sometimes called "vector irradiance". In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. A phrase assuming_condition indicates that the named quantity is the value which would obtain if all aspects of the system were unaltered except for the assumption of the circumstances specified by the condition. "Clear sky" means in the absence of clouds. The 3D ozone field acts as a reference ozone field in a diagnostic call to the model's radiation scheme. It is expressed in terms of mole fraction of ozone in air. It may be observation-based or model-derived. It may be from any time period. By using the same ozone reference in the diagnostic radiation call in two model simulations and calculating differences between the radiative flux diagnostics from the prognostic call to the radiation scheme and the diagnostic call to the radiation scheme with the ozone reference, an instantaneous radiative forcing for ozone can be calculated.

modis_cloud_area_fraction_cloud_water_path_effective_radius_ice

under discussion
Proposer: Brandon Duran
Proposed Date: 25 Jun 2024
Comments: #328
Ice means ice-topped clouds, as seen by the MODIS simulator. Dimensions of the histogram are cloud ice water path and cloud ice-crystal effective radius.

modis_cloud_area_fraction_cloud_water_path_effective_radius_liquid

under discussion
Proposer: Brandon Duran
Proposed Date: 25 Jun 2024
Comments: #328
Liquid means liquid-topped clouds, as seen by the MODIS simulator. Dimensions of the histogram are cloud liquid water path and cloud droplet effective radius.

modis_cloud_area_fraction_ice

under discussion
Proposer: Brandon Duran
Proposed Date: 25 Jun 2024
Comments: #328
Ice means ice-topped clouds, as seen by the MODIS simulator. Dimensions of the histogram are cloud top pressure and cloud optical depth.

modis_cloud_area_fraction_liquid

under discussion
Proposer: Brandon Duran
Proposed Date: 25 Jun 2024
Comments: #328
Liquid means liquid-topped clouds, as seen by the MODIS simulator. Dimensions of the histogram are cloud top pressure and cloud optical depth.

modis_cloud_area_fraction

under discussion
Proposer: Brandon Duran
Proposed Date: 25 Jun 2024
Comments: #328
The MODIS cloud area fraction is diagnosed from atmosphere model output by the MODIS simulator software in such a way as to be comparable with the observational diagnostics of MODIS (Moderate Resolution Imaging Spectroradiometer). Cloud area fraction is also called “cloud amount” and “cloud cover.” As seen from above, mean fraction of grid column occupied by cloud of optical depths and heights specified by the tau and pressure intervals given above. Dimensions of the histogram are cloud top pressure and cloud optical depth.

change_in_mean_sea_level_wrt_solid_surface

accepted
Proposer: Swati Gehlot
Proposed Date: 7 May 2024
Comments: #311
Units: m (ULAA)
New Term
The change in local mean sea level relative to the local solid surface, i.e. sea floor. The abbreviation "wrt" means "with respect to". A positive value means sea level rise.

wave_mixing_energy_flux_into_sea_water

under discussion
Proposer: Aurore Biardeau
Proposed Date: 13 May 2024
Comments: #317
Units: W m-2 (UFAA)
New Term

eastward_friction_velocity_in_sea_water

under discussion
Proposer: Aurore Biardeau
Proposed Date: 13 May 2024
Comments: #316
Units: m s-1 (UVAA)
New Term

global_average_sea_level_change_due_to_change_in_ocean_mass

accepted
Proposer: Aurore Biardeau, Stéphane Law-Chune
Proposed Date: 13 May 2024
Comments: #314
Global average mass volume sea level change is caused by water mass balance (evaporation – precipitation + runoff). This in turn results in a change in volume of the world ocean. Zero sea level change is an arbitrary level. 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. Because global average sea level change quantifies the change in volume of the world ocean, it is not calculated necessarily by considering local changes in mean sea level. This quantity is also called "barystatic sea level rise" or "barystatic sea level change". It is the part of global-mean sea-level rise which is due to the addition to the ocean of water mass that formerly resided within the land area (as land water storage or land ice) or in the atmosphere (which contains a relatively tiny mass of water).

mass_concentration_of_chlorophyll_a_in_sea_water_horizontal_gradient

under discussion
Proposer: Aurore Biardeau
Proposed Date: 13 May 2024
Comments: #315
'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'. 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. Chlorophyll-a is the most commonly occurring form of natural chlorophyll. The chemical formula of chlorophyll-a is C55H72O5N4Mg.

product_of_wind_speed_and_water_vapor_saturation_deficit_in_air

accepted
Proposer: Lee Kessenich
Proposed Date: 18 Apr 2024
Comments: #308
Units: Pa m s-1 (PAMS)
New Term
The product of windspeed and vapor pressure deficit is referred to as the Hot-Dry-Windy Index (HDW) for interpreting fire weather. It is a fire weather index that indicates the influence that the atmosphere has on a fire through wind, heat, and moisture (cf. https://www.bia.gov/sites/default/files/dup/assets/public/pdf/idc-020513.pdf). The units of HDW do not have an established physical significance for fire processes. As a fire weather index, it should be expressed in units of hPa m s-1.

nfdrs_10_hour_fuel_moisture

accepted
Proposer: Lee Kessenich
Proposed Date: 18 Apr 2024
Comments: #308
Units: % (UPCT)
New Term
10 hour fuel moisture (FM10) represents the modeled moisture content of dead fuels consisting of roundwood in the size range of one quarter to 1 inch in diameter and very roughly, the layer of litter extending from just below the surface to three-quarters of inch below the surface. The 10-hour timelag fuel moisture is a function of length of day (as influenced by latitude and calendar date), daily downwelling shortwave radiation, daily maximum temperature and minimum relative humidity, and daily precipitation values. It is a component in the US National Fire Danger Rating System (cf. https://www.bia.gov/sites/default/files/dup/assets/public/pdf/idc-020513.pdf). The US National Fire Danger Rating System comprises several numeric indexes that rate the potential over a large area for wildland fires to ignite, spread, and require action to suppress or manage. It was designed for use in the continental United States, and all its components are relative, not absolute.

nfdrs_1_hour_fuel_moisture

accepted
Proposer: Lee Kessenich
Proposed Date: 18 Apr 2024
Comments: #308
Units: % (UPCT)
New Term
1 hour fuel moisture (FM1) represents the modeled moisture content of dead fuels consisting of herbaceous plants or roundwood less than one-quarter inch in diameter. It also includes the uppermost layer of litter on the forest floor. The 1-hour timelag fuel moisture is a function of length of day (as influenced by latitude and calendar date), daily downwelling shortwave radiation, daily maximum temperature and minimum relative humidity, and daily precipitation values. It is a component in the US National Fire Danger Rating System (cf. https://www.bia.gov/sites/default/files/dup/assets/public/pdf/idc-020513.pdf). The US National Fire Danger Rating System comprises several numeric indexes that rate the potential over a large area for wildland fires to ignite, spread, and require action to suppress or manage. It was designed for use in the continental United States, and all its components are relative, not absolute .

acoustic_equivalent_area_in_sea_water

accepted
Proposer: John Horne, Mark Yamane, Rob Cermak
Proposed Date: 18 Mar 2024
Comments: #298
Units: m (ULAA)
New Term
Acoustic equivalent area is the squared area backscattering coefficient divided by the depth integral of squared volume backscattering coefficient. Area backscattering coefficient is the integral of the volume backscattering coefficient over a defined distance. Volume backscattering coefficient is the linear form of acoustic_volume_backscattering_strength_in_sea_water. The parameter is computed to provide a value that represents the area that would be occupied if all data cells contained the mean density and is the reciprocal of acoustic_index_of_aggregation_in_sea_water. For further details see Urmy et. al (2012) doi:10.1093/icesjms/fsr205 and Woillez et. al (2007) doi.org/10.1093/icesjms/fsm025.

acoustic_centre_of_mass_in_sea_water

accepted
Proposer: John Horne, Mark Yamane, Rob Cermak
Proposed Date: 18 Mar 2024
Comments: #298
Units: m (ULAA)
New Term
Acoustic centre of mass is the average of all sampled depths weighted by their volume backscattering coefficient. Volume backscattering coefficient is the linear form of acoustic_volume_backscattering_strength_in_sea_water. For further details see Urmy et. al (2012) doi:10.1093/icesjms/fsr205.

acoustic_proportion_occupied_in_sea_water

accepted
Proposer: John Horne, Mark Yamane, Rob Cermak
Proposed Date: 18 Mar 2024
Comments: #298
Units: 1 (UUUU)
New Term
Acoustic proportion occupied is occupied volume divided by the volume sampled. Occupied volume is the integral of the ratio of acoustic_volume_backscattering_strength_in_sea_water above -90 dB to the reference value, 1 m2 m-2. For further details see Urmy et. al (2012) doi:10.1093/icesjms/fsr205.

acoustic_index_of_aggregation_in_sea_water

accepted
Proposer: John Horne, Mark Yamane, Rob Cermak
Proposed Date: 18 Mar 2024
Comments: #298
Units: m-1 (UPRM)
New Term
Acoustic index of aggregation is the depth integral of squared volume backscattering coefficient divided by the squared area backscattering coefficient. Volume backscattering coefficient is the linear form of acoustic_volume_backscattering_strength_in_sea_water. Area backscattering coefficient is the integral of the volume backscattering coefficient over a defined distance. The parameter is computed to provide a value that represents the patchiness of biomass in the water column in the field of fisheries acoustics - the value is high when small areas are much denser than the rest of the distribution. The parameter is also the reciprocal of acoustic_equivalent_area_in_sea_water. For further details see Urmy et. al (2012) doi:10.1093/icesjms/fsr205 and Woillez et. al (2007) doi.org/10.1093/icesjms/fsm025.

acoustic_inertia_in_sea_water

accepted
Proposer: John Horne, Mark Yamane, Rob Cermak
Proposed Date: 18 Mar 2024
Comments: #298
Units: m-2 (PMSQ)
New Term
Acoustic inertia is the sum of squared distances from the acoustic_centre_of_mass weighted by the volume backscattering coefficient at each distance and normalized by the total area backscattering coefficient. Volume backscattering coefficient is the linear form of acoustic_volume_backscattering_strength_in_sea_water. Area backscattering coefficient is the integral of the volume backscattering coefficient over a defined distance. For further details see Urmy et. al (2012) doi:10.1093/icesjms/fsr205 and Bez and Rivoirard (2001) doi:10.1016/S0165-7836(00)00241-1.

spectral_width_of_radio_wave_in_air_scattered_by_air

accepted
Proposer: Ingemar Häggström
Proposed Date: 1 Oct 2021
Comments: #133
Units: Hz (UTHZ)
Updated term description
Frequency width of the radio wave, that was transmitted by an instrument and propagates in the air where it's scattered by the air due to which its properties change, and it is received by an instrument. The "instrument" (examples are radar and lidar) is the device used to make the observation. The "scatterers" are what causes the transmitted signal to be returned to the instrument (examples are aerosols, hydrometeors and refractive index irregularities in the air). A standard name referring to frequency spectra width of the signal received at the instrument.

change_in_sea_surface_height_due_to_change_in_air_pressure

accepted
Proposer: Aurore Biardeau, Stéphane Law-Chune
Proposed Date: 7 Mar 2024
Comments: 286
Sea surface height is a time-varying quantity. 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.

change_in_sea_floor_height_above_reference_ellipsoid_due_to_ocean_tide_loading

accepted
Proposer: Aurore Biardeau, Stéphane Law-Chune
Proposed Date: 7 Mar 2024
Comments: 288
Units: m (ULAA)
New Term
Sea surface height is a time-varying quantity. A reference ellipsoid is a regular mathematical figure that approximates the irregular shape of the geoid. A number of reference ellipsoids are defined for use in the field of geodesy. 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. Tides are a significant contributor to the observed sea surface height. The load tidal component of sea surface height describes the variability of the sea surface due to the deformation of the Earth because of the weight of the water masses displaced by ocean tides.

ocean_dynamic_sea_level

accepted
Proposer: Aurore Biardeau, Stéphane Law-Chune
Proposed Date: 7 Mar 2024
Comments: 285
Ocean dynamic sea level is the contribution to sea surface height variability made by processes other than astronomic forcing of the ocean and shallow water resonance of tidal components, or variations in air pressure. Sea surface height is a time-varying quantity.

aragonite_saturation_state_in_sea_water

under discussion
Proposer: Aurore Biardeau
Proposed Date: 5 Mar 2024
Comments: 284

upward_heat_flux_at_base_of_grounded_ice_sheet

under discussion
Proposer: Martin Jukes
Proposed Date: 30 Sep 2019
Comments:
Units: W m-2 (UFAA)
Term change from Term: upward_geothermal_heat_flux_at_ground_level_in_land_ice
"Land ice" means glaciers, ice-caps and ice-sheets resting on bedrock and also includes ice-shelves. "ground_level" means the land surface (including beneath snow, ice and surface water, if any). In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. "Upward" indicates a vector component which is positive when directed upward (negative downward). The quantity with standard name upward_heat_flux_at_base_of_grounded_ice_sheet is the upward heat flux at the interface between the ice and bedrock. It does not include any heat flux from the ocean into an ice shelf.

vegetation_roughtness_length

under discussion
Proposer: Yuling Wu
Proposed Date: 6 Aug 2020
Comments:
CF mailing list link: Standard name: AMSR products
Units: m (ULAA)
New Term
"Vegetation roughness" in fluid dynamics means the surface roughness caused by vegetation in impeding the flow.

lwe_frozen_precipitation_rate

under discussion
Proposer: Yuling Wu
Proposed Date: 6 Aug 2020
Comments:
CF mailing list link: Standard name: AMSR products
Units: m s-1 (UVAA)
New Term
"Frozen Precipitation" in the earth's atmosphere means precipitation of water in frozen phase only. The abbreviation "lwe" means liquid water equivalent.

ratio_of_sea_water_potential_temperature_anomaly_to_relaxation_timescale

under discussion
Proposer:
Proposed Date: None
Comments:
CF mailing list link:
Units: K s-1 (KPRS)
Updated term description
The quantity with standard name ratio_of_sea_water_potential_temperature_anomaly_to_relaxation_timescale is a correction term applied to modelled sea water potential temperature. The term is estimated as the deviation of model local sea water potential temperature from an observation-based climatology (e.g. World Ocean Database) weighted by a user-specified relaxation coefficient in s-1 (1/(relaxation timescale)). Potential temperature is the temperature a parcel of air or sea water would have if moved adiabatically to sea level pressure. The phrase "ratio_of_X_to_Y" means X/Y. The term "anomaly" means difference from climatology. It is strongly recommended to include a units_metadata attribute.

freezing_temperature_of_sea_water

under discussion
Proposer: Jonathan Gregory & Lars Barring
Proposed Date: 10 Jan 2024
Comments: #270
Units: K (UPKA)
Updated term description
It is strongly recommended that a variable with this standard name should have a units_metadata attribute, with one of the values "on-scale" or "difference", whichever is appropriate for the data, because it is essential to know whether the temperature is on-scale (meaning relative to the origin of the scale indicated by the units) or refers to temperature differences (implying that the origin of the temperature scale is irrevelant), in order to convert the units correctly (cf. https://cfconventions.org/cf-conventions/cf-conventions.html#temperature-units).

true_state_pressure

under discussion
Proposer: Matthias Schneider
Proposed Date: 27 Jan 2024
Comments: #199
Atmospheric pressures representing the true atmospheric state (analogous to the pressures representing the measured or modelled atmosphere).

eigenmode

under discussion
Proposer: Matthias Schneider
Proposed Date: 9 Jan 2024
Comments: #199
Modes representing different patterns (e.g. vertically correlated atmospheric patterns). Ordering is from most important modes to less important modes.

true_state_altitude

under discussion
Proposer: Matthias Schneider
Proposed Date: 9 Jan 2024
Comments: #199
Atmospheric altitudes representing the true atmospheric state (analogous to the altitudes representing the measured or modelled atmosphere).

virtual_potential_temperature_of_air

under discussion
Proposer: Simon Peatman
Proposed Date: 9 Dec 2022
Comments:
Units: K (UPKA)
New Term
The virtual potential temperature of air is the potential temperature at which the dry air constituent of a parcel of moist air would have the same density as the moist air at the same pressure.

virtual_temperature_of_air

under discussion
Proposer: Jonathan Gregory
Proposed Date: 9 Mar 2023
Comments:
Units: K (UPKA)
Term change from Term: virtual_temperature
The virtual temperature of air is the temperature at which the dry air constituent of a parcel of moist air would have the same density as the moist air at the same pressure.

water_surface_height_above_reference_datum

under discussion
Proposer: Fernando Manzano
Proposed Date: 30 May 2023
Comments:
Units: m (ULAA)
Updated term description
'Water surface height above reference datum' means the height of the upper surface of a body of liquid water, such as sea, lake or river, above an arbitrary reference datum. The altitude of the datum should be provided in a variable with standard name water_surface_reference_datum_altitude. The surface called "surface" means the lower boundary of the atmosphere. Nevertheless, the reference datum could be a geophysical surface, a height with respect to a geophysical surface, or a local benchmark attached to the land. Because the definition of the datum may vary from one place to another, spatial differences in actual tidal_sea_surface_height_above_reference_datum are not generally physically meaningful. However, local differences in this quantity over time are physically meaningful.

mass_fraction_of_frozen_water_in_air

under discussion
Proposer: Bjorn Stevens
Proposed Date: 30 Jul 2023
Comments:
The phrase "frozen_water" means ice. "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".

sea_ice_volume_fraction_of_ridged_ice

under discussion
Proposer: Aurore Biardeau
Proposed Date: 15 Jun 2023
Comments: #248
Units: 1 (UUUU)
New Term

cumulative_probability_of_air_temperature

new
Proposer: Klaus Zimmermann
Proposed Date: 22 Sep 2021
Comments:
Units: 1 (UUUU)
New Term
A probability percentile.

number_of_days_with_air_temperature_above_threshold

under discussion
Proposer: Klaus Zimmermann
Proposed Date: 23 Sep 2021
Comments:
Units: 1 (UUUU)
Updated term description
Air temperature is the bulk temperature of the air, not the surface (skin) temperature. A variable whose standard name has the form number_of_days_with_X_below|above_threshold is a count of the number of days on which the condition X_below|above_threshold is satisfied. It must have a climatological time variable, and a cell_methods entry for within days which describes the processing of quantity X before the threshold is applied. A number_of_days is an extensive quantity in time, and the cell_methods entry for over days should be "sum". It must give information about the threshold in one or both of the following two ways. With an explicit threshold in a coordinate variable or scalar coordinate variable with the standard name of X, or with a percentile threshold given in a scalar coordinate variable with the standard name cumulative_probability_of_X.

mass_concentration_of_greenalgae_expressed_as_chlorophyll_in_sea_water

under discussion
Proposer: Corinne Derval
Proposed Date: 13 Nov 2020
Comments:
Units: mg m-3 (UMMC)
New Term
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. Green Alge are small green unicellular flagellates caractherized by the presence of Chlorophyll b.

mass_concentration_of_prochlorococcus_expressed_as_chlorophyll_in_sea_water

under discussion
Proposer: Corinne Derval
Proposed Date: 13 Nov 2020
Comments:
Units: mg m-3 (UMMC)
New Term
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. Prochlorococcus are marine Prokaryotes with an extremely small cell, containing divinyl chlorophyll a and b as their primary photosynthetic pigments and adapted to the high-light, oligotrophic, warm waters of the tropical and subtropical regions of the world’s oceans.

mass_concentration_of_dinoflagellates_expressed_as_chlorophyll_in_sea_water

under discussion
Proposer: Corinne Derval
Proposed Date: 13 Nov 2020
Comments:
Units: mg m-3 (UMMC)
New Term
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. Dinoflagellates (dinophytes) are mostly unicellular, rarely colonial, biflagellated algae with cell walls firm, or reinforced with polygonal plates. They produce some of the most potent toxins known.

mass_concentration_of_prokaryotes_expressed_as_chlorophyll_in_sea_water

under discussion
Proposer: Corinne Derval
Proposed Date: 13 Nov 2020
Comments:
Units: mg m-3 (UMMC)
New Term
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. Prokaryotes group refers to those phytoplankters characterized by a prokaryotic cell and represents the main component of picophytoplankton.

mass_concentration_of_haptophytes_expressed_as_chlorophyll_in_sea_water

under discussion
Proposer: Corinne Derval
Proposed Date: 13 Nov 2020
Comments:
Units: mg m-3 (UMMC)
New Term
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. Haptophytes are mainly unicellular marine algae which play an important role in the DMSP production and in calcifying.

mass_concentration_of_cryptophytes_expressed_as_chlorophyll_in_sea_water

under discussion
Proposer: Corinne Derval
Proposed Date: 13 Nov 2020
Comments:
Units: mg m-3 (UMMC)
New Term
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. Cryptophytes are flaggellated unicellular organisms attributable to nanophytoplanktonic component, very rich in fatty acids and therefore a high quality food source for herbivorous zooplankton.

tidal_sea_surface_height_above_reference_datum

under discussion
Proposer: Fernando Manzano on behalf of the Copernicus Marine In Situ TAC Sea Level Reprocessed product Team
Proposed Date: 30 May 2023
Comments:
"Sea surface height" is a time-varying quantity. "Height_above_X" means the vertical distance above the named surface X, in this case above an arbitrary reference datum. The tidal component of sea surface height describes the predicted variability of the sea surface due to astronomic forcing (chiefly lunar and solar cycles) and shallow water resonance of tidal components; for example as generated based on harmonic analysis, or resulting from the application of harmonic tidal series as boundary conditions to a numerical tidal model. The reference datum could be a geophysical surface, a height with respect to a geophysical surface, or a local benchmark attached to the land. Because the definition of the datum may vary from one place to another, spatial differences in actual tidal_sea_surface_height_above_reference_datum are not generally physically meaningful. However, local differences in this quantity over time are physically meaningful.

mass_concentration_of_prokaryotes_expressed_as_carbon_in_sea_water

under discussion
Proposer: Gunnar Bratbak
Proposed Date: 4 Apr 2022
Comments:
Units: Kg m-3 (UKMC)
New Term
"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 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". 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. "Prokaryotes” are all Bacteria and Archaea excluding photosynthetic cyanobacteria such as Synechococcus and Prochlorococcus or other separately named components of the procaryotic population.

sea_floor_sediment_age_before_1950

under discussion
Proposer: Katrine Husum
Proposed Date: 4 Apr 2022
Comments:
Units: s (UTBB)
New Term
"sediment_age" means the length of time elapsed since the sediment was deposited. "before_1950" is a transparent representation of the phrase "before_present" used in the geological and archaeological domains to refer to time elapsed between an event and 1950 AD. "sea_floor_sediment" is sediment deposited at the sea bed.

mole_concentration_of_prokaryotes_expressed_as_carbon_in_sea_water

under discussion
Proposer: Gunnar Bratbak
Proposed Date: 4 Apr 2022
Comments:
Units: mol m-3 (MLM3)
New Term
Mole concentration means number of moles per unit volume, also called "molarity", and is used in the construction mole_concentration_of_X_in_Y, where X is a material constituent of Y. A chemical or biological species denoted by X may be described by a single term such as "nitrogen" or a phrase such as "nox_expressed_as_nitrogen". The 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. "Prokaryotes” are all Bacteria and Archaea excluding photosynthetic cyanobacteria such as Synechococcus and Prochlorococcus or other separately named components of the procaryotic population.

water_evapotranspiration_flux

under discussion
Proposer:
Proposed Date: None
Comments:
CF mailing list link:
Units: kg m-2 s-1 (KSP2)
Updated term description
Water means water in all phases. Evaporation is the conversion of liquid or solid into vapor. (The conversion of solid alone into vapor is called "sublimation".) The process of transpiration is not included. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. 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. In the versions before 56 transpiration was not mentioned and for versions 56 to 71 it was allowed to use water_evaporation_flux as an alias.

atmosphere_mass_content_of_rain

under discussion
Proposer: Yuling Wu
Proposed Date: 6 Aug 2020
Comments:
CF mailing list link: Standard name: AMSR products
Units: kg m-2 (KMP2)
New Term
"Content" indicates a quantity per unit area. The mass is the total mass of the molecules. 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. "Rain" means drops of water falling through the atmosphere that have a diameter greater than 0.5 mm.

water_potential_evapotranspiration_amount

under discussion
Proposer: Beate Geyer
Proposed Date: 18 Jun 2021
Comments:
Units: kg m-2 (KMP2)
New Term
"Water" means water in all phases. "Evapotranspiration" means all water vapor fluxes into the atmosphere from the surface: liquid evaporation, sublimation, and transpiration. Evaporation is the conversion of liquid or solid into vapor. Transpiration is the process by which water is carried from the roots of plants and evaporates from the stomata. (The conversion of solid alone into vapor is called "sublimation".) Potential evapotranspiration is the rate at which evaporation would take place under unaltered ambient conditions (temperature, relative humidity, wind, etc.) if the supply of water were unlimited, on the surface as if from an open water surface and unlimited in the soil. "Amount" means mass per unit area.

water_evapotranspiration_amount

under discussion
Proposer: Beate Geyer
Proposed Date: 18 Jun 2021
Comments:
Units: kg m-2 (KMP2)
New Term
Water means water in all phases. "Evapotranspiration" means all water vapor fluxes into the atmosphere from the surface: liquid evaporation, sublimation, and transpiration. Evaporation is the conversion of liquid or solid into vapor. Transpiration is the process by which water is carried from the roots of plants and evaporates from the stomata. (The conversion of solid alone into vapor is called "sublimation".) "Amount" means mass per unit area. Unless indicated in the cell_methods attribute, a quantity is assumed to apply to the whole area of each horizontal grid box.

downward_heat_flux_at_snow_base_in_snow

under discussion
Proposer: Martin Juckes
Proposed Date: 13 May 2020
Comments:
Units: W m-2 (UFAA)
Term change from Term: downward_heat_flux_at_ground_level_in_snow
"snow_base" means the bottom of a layer of snow which is lying on rock, soil or ice. "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.

spectral_slope_of_volume_absorption_coefficient_of_radiative_flux_in_sea_water_due_to_dissolved_organic_matter

under discussion
Proposer: Yannick Kern & Colin Stedmon
Proposed Date: 17 Mar 2023
Comments:
Units: m-1 (UPRM)
New Term
A measure of the dependency of the volume_absorption_coefficient_of_radiative_flux_in_sea_water_due_to_dissolved_organic_matter on wavelength. The wavelength range it has been calculated over is stated as an radiation_wavelength attribute (e.g. “275-295 nm”).

concentration_of_colored_dissolved_organic_matter_in_sea_water_expressed_as_fluorescence_in_raman_units

under discussion
Proposer: Yannick Kern & Colin Stedmon
Proposed Date: 17 Mar 2023
Comments:
Units: nm-1
New Term
Also commonly known as Chromophoric Dissolved Organic Matter (CDOM). CDOM plays an important role in the carbon cycling and biogeochemistry of coastal waters. It occurs naturally in aquatic environments primarily as a result of matter released from decaying plant and animal matter, which can enter coastal areas in river run-off containing organic materials leached from soils. Fluorescence intensity is normalised to the integrated Raman scattering peak of pure water from excitation at 350 nm, and therefore reported in Raman Units. The wavelengths that fluorescence is measured at will depend on the sensor used and is stated as an radiation_wavelength attribute (eg. “Ex350nm Em460nm”).

water_volume_contained_in_river_channel

under discussion
Proposer: Dikra Khedhaouiria
Proposed Date: 6 Oct 2021
Comments: Github #134 1.
Units: m3 (MCUB)
New Term
The river_channel represents a body of water flowing along a natural channel and storage refers to the amount of water stored in that channel.

mass_concentration_of_phycoerythrin_5_in_sea_water

under discussion
Proposer: Fernando Carvalho Pacheco & Fernando Santiago-Mandujano & Karin Bjorkman & Andrew Barna
Proposed Date: 19 Oct 2021
Comments: Github #135 8.
"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 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". “Phycoerythrin-5” is the concentration of phycoerythrin in the 10-5 µm fractions per unit volume of the water body.

enrichment_of_15N_in_particulate_nitrogen_in_particles_in_sea_water_expressed_as_lowercase_delta_15N_relative_to_atmospheric_nitrogen

under discussion
Proposer: Fernando Carvalho Pacheco & Fernando Santiago-Mandujano & Karin Bjorkman & Andrew Barna
Proposed Date: 19 Oct 2021
Comments: Github #135 17. Is this the same as term 10? (Term 18 withdrawn as duplicate of term 11).
Isotopic enrichment of 15N, often called d15N or delta 15N (lower case delta), is a measure of the ratio of stable isotopes 15N:14N. Reference: Karl, D. (2018) Sediment trap flux measurements from the Hawaii Ocean Time-Series (HOT) project at station ALOHA. Biological and Chemical Oceanography Data Management Office (BCO-DMO). doi:10.1575/1912/bco-dmo.737393.1.

mass_concentration_of_phycoerythrin_10_in_sea_water

under discussion
Proposer: Fernando Carvalho Pacheco & Fernando Santiago-Mandujano & Karin Bjorkman & Andrew Barna
Proposed Date: 19 Oct 2021
Comments: Github #135 9.
"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 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". “Phycoerythrin-10” is the concentration of phycoerythrin >10 µm fractions per unit volume of the water body.

mass_concentration_of_phycoerythrin_4_in_sea_water

under discussion
Proposer: Fernando Carvalho Pacheco & Fernando Santiago-Mandujano & Karin Bjorkman & Andrew Barna
Proposed Date: 19 Oct 2021
Comments: Github #135 7.
"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 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". “Phycoerythrin-4” is the concentration of phycoerythrin in the 5-0.4 µm fractions per unit volume of the water body.

spectral_width_of_radio_wave_scattered_by_air

accepted
Proposer: Ingemar Häggström
Proposed Date: 1 Oct 2021
Comments: #133
Units: Hz (UTHZ)
New Term
The "instrument" (examples are radar and lidar) is the device used to make the observation. The "scatterers" are what causes the transmitted signal to be returned to the instrument (examples are aerosols, hydrometeors and refractive index irregularities), of whatever kind the instrument detects. A standard name referring to frequency width of the received signal.

received_power_of_radio_wave_scattered_by_air

accepted
Proposer: Ingemar Häggström
Proposed Date: 1 Oct 2021
Comments: #133
Units: W (WATT)
New Term
The "instrument" (examples are radar and lidar) is the device used to make the observation. The "scatterers" are what causes the transmitted signal to be returned to the instrument (examples are aerosols, hydrometeors and refractive index irregularities), of whatever kind the instrument detects. A standard name referring to the recieved power of the signal at the instrument.

radio_signal_roundtrip_travel_time_in_air

accepted
Proposer: Ingemar Häggström
Proposed Date: 1 Oct 2021
Comments: #133
Units: s (UTBB/)
New Term
The "instrument" (examples are radar and lidar) is the device used to make the observation. The "scatterers" are what causes the transmitted signal to be returned to the instrument (examples are aerosols, hydrometeors and refractive index irregularities), of whatever kind the instrument detects. A standard name referring to time taken for a signal to propagate from the emitting instrument to a reflecting volume and back again to the instrument.

northward_storm_velocity

under discussion
Proposer: Emily Schlie, Eric Engle, and the CAMPS team (NOAA MDL)
Proposed Date: 22 Dec 2020
Comments:
CF mailing list link: Standard names: **
Units: m s-1 (UVAA)
New Term
The northward component of storm_motion. "Northward" indicates a vector component which is positive when directed northward (negative southward). Storm_motion is defined as the average speed of a storm and the direction the storm will move from.

eastward_storm_velocity

under discussion
Proposer: Emily Schlie, Eric Engle, and the CAMPS team
Proposed Date: 22 Dec 2020
Comments:
CF mailing list link: Standard names: **
Units: m s-1 (UVAA)
New Term
The eastward component of storm motion. “Eastward” indicates a vector component which is positive when directed eastward (negative westward). Storm motion is defined as the average speed of a storm and the direction the storm will move from.

residuum_of_soil_water_content

under discussion
Proposer: Ronny Petrik and Klaus Keuler and Burkhardt Rockel
Proposed Date: 20 May 2021
Comments:
Units: kg m-2 (KMP2)
New Term
"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 those layer of the soil model which is the lowermost hydrological active layer. For the content between specified levels in the soil, standard names including "content_of_soil_layer" are used. "Residuum" is defined by the difference between the tendency of the soil moisture content over a specific time period (left hand side of soil water equation) and the sum of the sources and sinks of soil water over the same time period (right hand side of equation). A positive value means that the soil becomes falsely wetter in a model and a negative value means the soil becomes falsely dryer. It should be noted, that the residuum has to be calculated excluding climatological layers where the temperature or the soil water content is kept to a climatological value or a value given by another soil layer.

sea_surface_wave_variance_spectral_density_attenuation_coefficient_due_to_icebergs

under discussion
Proposer: Andy Saulter
Proposed Date: 21 Dec 2020
Comments:
Units: 1 (UUUU)
New Term
The attenuation coefficient is the fractional reduction of sea_surface_wave_variance_spectral_density due to the stated process. Attenuation is the sum of absorption and scattering.

sea_water_temperature_anomaly

new
Proposer:
Proposed Date: None
Comments:
CF mailing list link:
Units: K (UPKA)
Updated term description
The term "anomaly" means difference from climatology. Sea water temperature is the in situ temperature of the sea water. To specify the depth at which the temperature anomaly applies, use a vertical coordinate variable or scalar coordinate variable. To specify the reference (baseline) epoch to which the quantity applies, provide a scalar coordinate variable with standard name reference_epoch.

surface_roughness_length_due_to_vegetation

under discussion
Proposer: Yuling Wu
Proposed Date: 6 Aug 2020
Comments:
Units: m (ULAA)
New Term
"Vegetation roughness" in fluid dynamics means the surface roughness caused by vegetation in impeding the flow.

lwe_solid_precipitation_rate

under discussion
Proposer: Yuling Wu
Proposed Date: 6 Aug 2020
Comments:
Units: m s-1 (UVAA)
New Term
"Frozen Precipitation" in the earth's atmosphere means precipitation of water in frozen phase only. The abbreviation "lwe" means liquid water equivalent.

mass_concentration_of_pm10_chloride_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: 29 Jun 2020
Comments: Linked to discussion of "dry_aerosol" in https://github.com/cf-convention/discuss/issues/61.
Units: kg m-3 (UKMC)
New Term
"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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. "Pm10 aerosol" means atmospheric particulate compounds with an aerodynamic diameter of less than or equal to 10 micrometers. The chemical formula for chloride is Cl-.

mass_concentration_of_pm10_ammonium_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: 29 Jun 2020
Comments: Linked to discussion of "dry_aerosol" in https://github.com/cf-convention/discuss/issues/61.
Units: kg m-3 (UKMC)
New Term
"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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. "Pm10 aerosol" means atmospheric particulate compounds with an aerodynamic diameter of less than or equal to 10 micrometers. The chemical formula for ammonium is NH4.

mass_concentration_of_pm10_sulfate_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: 29 Jun 2020
Comments: Linked to discussion of "dry_aerosol" in https://github.com/cf-convention/discuss/issues/61.
Units: kg m-3 (UKMC)
New Term
"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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. "Pm10 aerosol" means atmospheric particulate compounds with an aerodynamic diameter of less than or equal to 10 micrometers. The chemical formula for the sulfate anion is SO4(2-).

mass_concentration_of_pm10_nitrate_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: 29 Jun 2020
Comments: Linked to discussion of "dry_aerosol" in https://github.com/cf-convention/discuss/issues/61.
Units: kg m-3 (UKMC)
New Term
"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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. "Pm10 aerosol" means atmospheric particulate compounds with an aerodynamic diameter of less than or equal to 10 micrometers. The chemical formula for the nitrate anion is NO3-.

mass_concentration_of_pm10_magnesium_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: 29 Jun 2020
Comments: Linked to discussion of "dry_aerosol" in https://github.com/cf-convention/discuss/issues/61.
Units: kg m-3 (UKMC)
New Term
"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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. "Pm10 aerosol" means atmospheric particulate compounds with an aerodynamic diameter of less than or equal to 10 micrometers. The chemical formula for the magnesium dication is Mg(2+).

mass_concentration_of_pm10_potassium_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: 29 Jun 2020
Comments: Linked to discussion of "dry_aerosol" in https://github.com/cf-convention/discuss/issues/61.
Units: kg m-3 (UKMC)
New Term
"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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. "Pm10 aerosol" means atmospheric particulate compounds with an aerodynamic diameter of less than or equal to 10 micrometers. The chemical formula for the potassium cation is K+.

mass_concentration_of_pm10_calcium_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: 29 Jun 2020
Comments: Linked to discussion of "dry_aerosol" in https://github.com/cf-convention/discuss/issues/61.
Units: kg m-3 (UKMC)
New Term
"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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. "Pm10 aerosol" means atmospheric particulate compounds with an aerodynamic diameter of less than or equal to 10 micrometers. The chemical formula for the calcium dication is Ca(2+).

mass_concentration_of_pm10_sodium_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: 29 Jun 2020
Comments: Linked to discussion of "dry_aerosol" in https://github.com/cf-convention/discuss/issues/61.
Units: kg m-3 (UKMC)
New Term
"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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. "Pm10 aerosol" means atmospheric particulate compounds with an aerodynamic diameter of less than or equal to 10 micrometers. The chemical formula for the sodium cation is Na+.

mass_concentration_of_pm10_methanesulfonic_acid_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: 29 Jun 2020
Comments: Linked to discussion of "dry_aerosol" in https://github.com/cf-convention/discuss/issues/61.
Units: kg m-3 (UKMC)
New Term
"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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. "Pm10 aerosol" means atmospheric particulate compounds with an aerodynamic diameter of less than or equal to 10 micrometers. The chemical formula for methanesulfonic acid is CH3SO3H.

mass_concentration_of_pm10_bromide_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: 29 Jun 2020
Comments: Linked to discussion of "dry_aerosol" in https://github.com/cf-convention/discuss/issues/61.
Units: kg m-3 (UKMC)
New Term
"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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. "Pm10 aerosol" means atmospheric particulate compounds with an aerodynamic diameter of less than or equal to 10 micrometers. The chemical formula for the bromide anion is Br-.

mass_concentration_of_pm10_oxalate_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: 29 Jun 2020
Comments: Linked to discussion of "dry_aerosol" in https://github.com/cf-convention/discuss/issues/61.
Units: kg m-3 (UKMC)
New Term
"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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. "Pm10 aerosol" means atmospheric particulate compounds with an aerodynamic diameter of less than or equal to 10 micrometers. The chemical formula for the oxalate dianion is C2O4(2-).

lake_mixed_layer_thickness

new
Proposer: Beate Geyer and Burkhardt Rockel
Proposed Date: 21 Aug 2020
Comments:
CF mailing list link: Standard names: lake variables
Units: m (ULAA)
New Term
The lake mixed layer is the upper part of the ocean, regarded as being well-mixed. Various criteria are used to define the mixed layer; this can be specified by using a standard name of lake_mixed_layer_defined_by_X. "Thickness" means the vertical extent of a layer.

lake_water_temperature

new
Proposer: Beate Geyer and Burkhardt Rockel
Proposed Date: 21 Aug 2020
Comments:
CF mailing list link: Standard names: lake variables
Units: degree (UAAA)
New Term
Lake water temperature is the in situ temperature of the lake water. To specify the depth at which the temperature applies use a vertical coordinate variable or scalar coordinate variable.

lake_floor_depth_below_lake_surface

new
Proposer: Beate Geyer and Burkhardt Rockel
Proposed Date: 21 Aug 2020
Comments:
CF mailing list link: Standard names: lake variables
Units: m (ULAA)
New Term
The lake_floor_depth_below_lake_surface is the vertical distance between the lake surface and the lake bed as measured at a given point in space.

toa_longwave_dust_ambient_aerosol_direct_radiative_effect_assuming_clear_sky

under discussion
Proposer: Martin Juckes
Proposed Date: 24 Apr 2019
Comments:
Units: W m-2 (UFAA)
Term change from Term: toa_longwave_dust_ambient_aerosol_particles_direct_radiative_effect_assuming_clear_sky
The abbreviation "toa" means top of atmosphere. The term "longwave" means longwave radiation. "X_direct_radiative_effect" refers to the instantaneous radiative impact of X on the Earth's energy balance, excluding secondary effects such as changes in cloud cover which may be caused by X. A positive radiative forcing or radiative effect is equivalent to a downward radiative flux and contributes to a warming of the earth system. "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. "Ambient_aerosol" means that the aerosol is measured or modelled at the ambient state of pressure, temperature and relative humidity that exists in its immediate environment. A phrase "assuming_condition" indicates that the named quantity is the value which would obtain if all aspects of the system were unaltered except for the assumption of the circumstances specified by the condition. "Clear sky" means in the absence of clouds.

surface_longwave_dust_ambient_aerosol_direct_radiative_effect_assuming_clear_sky

under discussion
Proposer: Martin Juckes
Proposed Date: 24 Apr 2019
Comments:
Units: W m-2 (UFAA)
Term change from Term: surface_net_downward_longwave_dust_ambient_aerosol_particles_direct_radiative_effect_assuming_clear_sky
The surface called "surface" means the lower boundary of the atmosphere. The term "longwave" means longwave radiation. "X_direct_radiative_effect" refers to the instantaneous radiative impact of X on the Earth's energy balance, excluding secondary effects such as changes in cloud cover which may be caused by X. A positive radiative forcing or radiative effect is equivalent to a downward radiative flux and contributes to a warming of the earth system. "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. "Ambient_aerosol" means that the aerosol is measured or modelled at the ambient state of pressure, temperature and relative humidity that exists in its immediate environment. A phrase "assuming_condition" indicates that the named quantity is the value which would obtain if all aspects of the system were unaltered except for the assumption of the circumstances specified by the condition. "Clear sky" means in the absence of clouds.

surface_shortwave_dust_ambient_aerosol_direct_radiative_effect_assuming_clear_sky

under discussion
Proposer: Martin Juckes
Proposed Date: 24 Apr 2019
Comments:
Units: W m-2 (UFAA)
Term change from Term: surface_net_downward_shortwave_dust_ambient_aerosol_particles_direct_radiative_effect_assuming_clear_sky
The surface called "surface" means the lower boundary of the atmosphere. The term "shortwave" means shortwave radiation. "X_direct_radiative_effect" refers to the instantaneous radiative impact of X on the Earth's energy balance, excluding secondary effects such as changes in cloud cover which may be caused by X. A positive radiative forcing or radiative effect is equivalent to a downward radiative flux and contributes to a warming of the earth system. "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. "Ambient_aerosol" means that the aerosol is measured or modelled at the ambient state of pressure, temperature and relative humidity that exists in its immediate environment. A phrase "assuming_condition" indicates that the named quantity is the value which would obtain if all aspects of the system were unaltered except for the assumption of the circumstances specified by the condition. "Clear sky" means in the absence of clouds.

surface_shortwave_dust_ambient_aerosol_direct_radiative_effect

under discussion
Proposer: Martin Juckes
Proposed Date: 24 Apr 2019
Comments:
Units: W m-2 (UFAA)
Term change from Term: surface_net_downward_shortwave_dust_ambient_aerosol_particles_direct_radiative_effect
The surface called "surface" means the lower boundary of the atmosphere. The term "shortwave" means shortwave radiation. "X_direct_radiative_effect" refers to the instantaneous radiative impact of X on the Earth's energy balance, excluding secondary effects such as changes in cloud cover which may be caused by X. A positive radiative forcing or radiative effect is equivalent to a downward radiative flux and contributes to a warming of the earth system. "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. "Ambient_aerosol" means that the aerosol is measured or modelled at the ambient state of pressure, temperature and relative humidity that exists in its immediate environment.

surface_longwave_dust_ambient_aerosol_direct_radiative_effect

under discussion
Proposer: Martin Juckes
Proposed Date: 24 Apr 2019
Comments:
Units: W m-2 (UFAA)
Term change from Term: surface_net_downward_longwave_dust_ambient_aerosol_particles_direct_radiative_effect
The surface called "surface" means the lower boundary of the atmosphere. The term "longwave" means longwave radiation. "X_direct_radiative_effect" refers to the instantaneous radiative impact of X on the Earth's energy balance, excluding secondary effects such as changes in cloud cover which may be caused by X. A positive radiative forcing or radiative effect is equivalent to a downward radiative flux and contributes to a warming of the earth system. "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. "Ambient_aerosol" means that the aerosol is measured or modelled at the ambient state of pressure, temperature and relative humidity that exists in its immediate environment.

upward_turbulent_heat_flux_in_air

under discussion
Proposer: Martin Juckes / Alison Pamment
Proposed Date: 4 Jul 2018
Comments: Arising from LS3MIP discussion.
Units: W m-2 (UFAA)
Term change from Term: upward_sensible_heat_flux_in_air
"Upward" indicates a vector component which is positive when directed upward (negative downward). The "turbulent heat flux" is the exchange of heat caused by the motion of air. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics.

surface_downward_turbulent_heat_flux

under discussion
Proposer: Martin Juckes / Alison Pamment
Proposed Date: 4 Jul 2018
Comments: Arising from LS3MIP discussion.
Units: W m-2 (UFAA)
Term change from Term: surface_downward_sensible_heat_flux
The surface called "surface" means the lower boundary of the atmosphere. "Downward" indicates a vector component which is positive when directed downward (negative upward). The "turbulent heat flux" is the exchange of heat between the surface and the air by motion of air. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics.

surface_upward_turbulent_heat_flux

under discussion
Proposer: Martin Juckes / Alison Pamment
Proposed Date: 4 Jul 2018
Comments: Arising from LS3MIP discussion.
Units: W m-2 (UFAA)
Term change from Term: surface_upward_sensible_heat_flux
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 "turbulent heat flux" is the exchange of heat between the surface and the air by motion of air. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. 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.

integral_wrt_time_of_surface_downward_turbulent_heat_flux

under discussion
Proposer: Martin Juckes / Alison Pamment
Proposed Date: 4 Jul 2018
Comments: Arising from LS3MIP discussion.
Units: W s m-2 (WSMM)
Term change from Term: integral_wrt_time_of_surface_downward_sensible_heat_flux
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. "wrt" means with respect to. The surface called "surface" means the lower boundary of the atmosphere. "Downward" indicates a vector component which is positive when directed downward (negative upward). The "turbulent heat flux" is the exchange of heat between the surface and the air by motion of air. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics.

isotope_ratio_of_2H_to_1H_in_sea_water_excluding_solutes_and_solids

under discussion
Proposer: Martin Juckes
Proposed Date: 3 Apr 2018
Comments: CMIP6 - PMIP. 12.
Units: 1 (UUUU)
New Term
The phrase "ratio_of_X_to_Y" means X/Y. The phrase "isotope_ratio" is used in the construction isotope_ratio_of_A_to_B where A and B are both named isotopes. It means the ratio of the number of atoms of A to the number of atoms of B present within a medium. "H" means the element "hydrogen" and "2H" is the stable isotope "hydrogen-2", usually called "deuterium". "1H" is the stable isotope "hydrogen-1". The phrase "in_sea_water_excluding_solutes_and_solids" means that the standard name refers to the composition of the sea water medium itself and does not include material that may be dissolved or suspended in the medium.

atmosphere_mole_content_of_semiheavy_water_vapor

under discussion
Proposer: Maarten Sneep
Proposed Date: 23 Feb 2018
Comments:
"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 construction "atmosphere_mole_content_of_X" means the vertically integrated number of moles of X above a unit area. The chemical formula for semi-heavy water is HDO, water with one hydrogen replaced by deuterium.

mass_concentration_of_chloride_dry_aerosol_particles_in_air

under discussion
Proposer: Daniel Neumann
Proposed Date: 18 May 2017
Comments:
Units: kg m-3 (UKMC)
New Term
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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. The chemical formula for chloride is Cl-.

mass_fraction_of_chloride_dry_aerosol_particles_in_air

under discussion
Proposer: Daniel Neumann
Proposed Date: 18 May 2017
Comments:
Units: 1 (UUUU)
New Term
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 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". "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. Aerosol particles take up ambient water (a process known as hygroscopic growth) depending on the relative humidity and the composition of the particles. "Dry aerosol particles" means aerosol particles without any water uptake. The chemical formula for chloride is Cl-.

vertical_component_of_curl_of_surface_downward_stress

under discussion
Proposer: Bruce Hackett
Proposed Date: 19 Jan 2016
Comments:
Units: N m-3 (NCUM)
New Term
The surface downward stress is the wind stress on the surface. The quantity with standard name vertical_component_of_curl_of_surface_downward_stress is a signed scalar that represents the magnitude of the 2D surface wind downward stress vector field's local anti-clock-wise rotation at a given point; clockwise rotation is thus given as negative curl. The surface called "surface" means the lower boundary of the atmosphere. "Downward" indicates a downward flux of momentum, which accelerates the lower medium along the vector and the upper medium against the vector.

divergence_of_surface_downward_stress

under discussion
Proposer: Bruce Hackett
Proposed Date: 19 Jan 2016
Comments:
Units: N m-3 (NCUM)
New Term
The surface downward stress is the wind stress on the surface. The quantity with standard name divergence_of_surface_downward_stress is a signed scalar that represents the magnitude of the 2D surface wind downward stress vector field's source (positive) or sink (negative) at a given point. The surface called "surface" means the lower boundary of the atmosphere.