CFSN0395 sea_water_potential_density Sea water potential density is the density a parcel of sea water would have if moved adiabatically to a reference pressure, by default assumed to be sea level pressure. To specify the reference pressure to which the quantity applies, provide a scalar coordinate variable with standard name reference_pressure. The density of a substance is its mass per unit volume. For sea water potential density, if 1000 kg m-3 is subtracted, the standard name sea_water_sigma_theta should be chosen instead. M HEXD0ZQ7 sea_surface_primary_swell_wave_from_direction_at_variance_spectral_density_maximum The quantity with standard name sea_surface_primary_swell_wave_from_direction_at_variance_spectral_density_maximum is the direction from which the most energetic waves are coming in the primary swell wave component of a sea. Swell waves are waves on the ocean surface and are the low frequency portion of a bimodal wave frequency spectrum. The primary swell wave is the most energetic swell wave in the low frequency portion of a bimodal wave frequency spectrum. The spectral peak is the most energetic wave in the wave spectrum partition. The phrase "from_direction" is used in the construction X_from_direction and indicates the direction from which the velocity vector of X is coming. The direction is a bearing in the usual geographical sense, measured positive clockwise from due north. The wave directional spectrum can be written as a five dimensional function S(t,x,y,f,theta) where t is time, x and y are horizontal coordinates (such as longitude and latitude), f is frequency and theta is direction. S has the standard name sea_surface_wave_directional_variance_spectral_density. S can be integrated over direction to give S1= integral(S dtheta) and this quantity has the standard name sea_surface_wave_variance_spectral_density. I 0UJ6J2B3 sea_surface_secondary_swell_wave_from_direction_at_variance_spectral_density_maximum The quantity with standard name sea_surface_secondary_swell_wave_from_direction_at_variance_spectral_density_maximum is the direction from which the most energetic waves are coming in the secondary swell wave component of a sea. Swell waves are waves on the ocean surface and are the low frequency portion of a bimodal wave frequency spectrum. The secondary swell wave is the second most energetic wave in the low frequency portion of a bimodal wave frequency spectrum. The spectral peak is the most energetic wave in the wave spectrum partition. The phrase "from_direction" is used in the construction X_from_direction and indicates the direction from which the velocity vector of X is coming. The direction is a bearing in the usual geographical sense, measured positive clockwise from due north. The wave directional spectrum can be written as a five dimensional function S(t,x,y,f,theta) where t is time, x and y are horizontal coordinates (such as longitude and latitude), f is frequency and theta is direction. S has the standard name sea_surface_wave_directional_variance_spectral_density. S can be integrated over direction to give S1= integral(S dtheta) and this quantity has the standard name sea_surface_wave_variance_spectral_density. I 2RVRF04V sea_surface_tertiary_swell_wave_from_direction_at_variance_spectral_density_maximum The quantity with standard name sea_surface_tertiary_swell_wave_from_direction_at_variance_spectral_density_maximum is the direction from which the most energetic waves are coming in the tertiary swell wave component of a sea. Swell waves are waves on the ocean surface and are the low frequency portion of a bimodal wave frequency spectrum. The tertiary swell wave is the third most energetic swell wave in the low frequency portion of a bimodal wave frequency spectrum. The spectral peak is the most energetic wave in the wave spectrum partition. The phrase "from_direction" is used in the construction X_from_direction and indicates the direction from which the velocity vector of X is coming. The direction is a bearing in the usual geographical sense, measured positive clockwise from due north. The wave directional spectrum can be written as a five dimensional function S(t,x,y,f,theta) where t is time, x and y are horizontal coordinates (such as longitude and latitude), f is frequency and theta is direction. S has the standard name sea_surface_wave_directional_variance_spectral_density. S can be integrated over direction to give S1= integral(S dtheta) and this quantity has the standard name sea_surface_wave_variance_spectral_density. I SWHZTDD9 sea_surface_swell_wave_period_at_variance_spectral_density_maximum The quantity with standard name sea_surface_swell_wave_period_at_variance_spectral_density_maximum is the period of the most energetic waves within the swell wave component of a sea. Swell waves are waves on the ocean surface and are the low frequency portion of a bimodal wave frequency spectrum. A period is an interval of time, or the time-period of an oscillation. Wave period is the interval of time between repeated features on the waveform such as crests, troughs or upward passes through the mean level. The phrase "wave_period_at_variance_spectral_density_maximum", sometimes called peak wave period, describes the period of the most energetic waves within a given sub-domain of the wave spectrum. I NPOHAN1Y mass_concentration_of_biological_taxon_expressed_as_carbon_in_sea_water "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. Mass concentration of biota expressed as carbon is also referred to as "carbon biomass". "Biological taxon" is a name or other label identifying an organism or a group of organisms as belonging to a unit of classification in a hierarchical taxonomy. There must be an auxiliary coordinate variable with standard name biological_taxon_name to identify the taxon in human readable format and optionally an auxiliary coordinate variable with standard name biological_taxon_identifier to provide a machine-readable identifier. See Section 6.1.2 of the CF convention (version 1.8 or later) for information about biological taxon auxiliary coordinate variables. I K1HC6TUK mole_concentration_of_biological_taxon_expressed_as_nitrogen_in_sea_water "Mole concentration" means number of moles per unit volume, also called "molarity", and is used in the construction "mole_concentration_of_X_in_Y", where X is a material constituent of Y. A chemical 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. "Biological taxon" is a name or other label identifying an organism or a group of organisms as belonging to a unit of classification in a hierarchical taxonomy. There must be an auxiliary coordinate variable with standard name biological_taxon_name to identify the taxon in human readable format and optionally an auxiliary coordinate variable with standard name biological_taxon_identifier to provide a machine-readable identifier. See Section 6.1.2 of the CF convention (version 1.8 or later) for information about biological taxon auxiliary coordinate variables. I CFSN0329 sea_water_potential_temperature Sea water potential temperature is the temperature a parcel of sea water would have if moved adiabatically to sea level pressure. M 8FB20X47 mass_concentration_of_biological_taxon_expressed_as_nitrogen_in_sea_water "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. Mass concentration of biota expressed as nitrogen is also referred to as "nitrogen biomass". "Biological taxon" is a name or other label identifying an organism or a group of organisms as belonging to a unit of classification in a hierarchical taxonomy. There must be an auxiliary coordinate variable with standard name biological_taxon_name to identify the taxon in human readable format and optionally an auxiliary coordinate variable with standard name biological_taxon_identifier to provide a machine-readable identifier. See Section 6.1.2 of the CF convention (version 1.8 or later) for information about biological taxon auxiliary coordinate variables. I FU8M33BF number_concentration_of_biological_taxon_in_sea_water "Number concentration" means the number of particles or other specified objects per unit volume. "Biological taxon" is a name or other label identifying an organism or a group of organisms as belonging to a unit of classification in a hierarchical taxonomy. There must be an auxiliary coordinate variable with standard name biological_taxon_name to identify the taxon in human readable format and optionally an auxiliary coordinate variable with standard name biological_taxon_identifier to provide a machine-readable identifier. See Section 6.1.2 of the CF convention (version 1.8 or later) for information about biological taxon auxiliary coordinate variables. I UMJTVO1O mass_concentration_of_biological_taxon_expressed_as_chlorophyll_in_sea_water "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. "Biological taxon" is a name or other label identifying an organism or a group of organisms as belonging to a unit of classification in a hierarchical taxonomy. There must be an auxiliary coordinate variable with standard name biological_taxon_name to identify the taxon in human readable format and optionally an auxiliary coordinate variable with standard name biological_taxon_identifier to provide a machine-readable identifier. See Section 6.1.2 of the CF convention (version 1.8 or later) for information about biological taxon auxiliary coordinate variables. 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. I 7IQMB8XJ mole_concentration_of_biological_taxon_expressed_as_carbon_in_sea_water "Mole concentration" means number of moles per unit volume, also called "molarity", and is used in the construction "mole_concentration_of_X_in_Y", where X is a material constituent of Y. A chemical 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. "Biological taxon" is a name or other label identifying an organism or a group of organisms as belonging to a unit of classification in a hierarchical taxonomy. There must be an auxiliary coordinate variable with standard name biological_taxon_name to identify the taxon in human readable format and optionally an auxiliary coordinate variable with standard name biological_taxon_identifier to provide a machine-readable identifier. See Section 6.1.2 of the CF convention (version 1.8 or later) for information about biological taxon auxiliary coordinate variables. I KZRZCYPD sea_surface_swell_wave_from_direction_at_variance_spectral_density_maximum The quantity with standard name sea_surface_swell_wave_from_direction_at_variance_spectral_density_maximum is the direction from which the most energetic waves are coming in the swell wave component of a sea. Swell waves are waves on the ocean surface and are the low frequency portion of a bimodal wave frequency spectrum. The spectral peak is the most energetic wave in the wave spectrum partition. The phrase "from_direction" is used in the construction X_from_direction and indicates the direction from which the velocity vector of X is coming. The direction is a bearing in the usual geographical sense, measured positive clockwise from due north. The swell wave directional spectrum can be written as a five dimensional function S(t,x,y,f,theta) where t is time, x and y are horizontal coordinates (such as longitude and latitude), f is frequency and theta is direction. S has the standard name sea_surface_wave_directional_variance_spectral_density. S can be integrated over direction to give S1= integral(S dtheta) and this quantity has the standard name sea_surface_wave_variance_spectral_density. I 9334Z59K reference_pressure A constant pressure value, typically representative of mean sea level pressure, which can be used in defining coordinates or functions of state. I E91KVDAN sea_surface_wind_wave_from_direction_at_variance_spectral_density_maximum The quantity with standard name sea_surface_wind_wave_from_direction_at_variance_spectral_density_maximum is the direction from which the most energetic waves are coming in the wind wave component of a sea. Wind waves are waves on the ocean surface and are the high frequency portion of a bimodal wave frequency spectrum. The spectral peak is the most energetic wave in the wave spectrum partition. The phrase "from_direction" is used in the construction X_from_direction and indicates the direction from which the velocity vector of X is coming. The direction is a bearing in the usual geographical sense, measured positive clockwise from due north. The wave directional spectrum can be written as a five dimensional function S(t,x,y,f,theta) where t is time, x and y are horizontal coordinates (such as longitude and latitude), f is frequency and theta is direction. S has the standard name sea_surface_wave_directional_variance_spectral_density. S can be integrated over direction to give S1= integral(S dtheta) and this quantity has the standard name sea_surface_wave_variance_spectral_density. I SZQEEQA7 mass_concentration_of_zooplankton_expressed_as_carbon_in_sea_water "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. "Zooplankton" means the total zooplankton population, with components such as mesozooplankton, microzooplankton and miscellaneous zooplankton. I CFSN0014 air_potential_temperature Air potential temperature is the temperature a parcel of air would have if moved dry adiabatically to a standard pressure, typically representative of mean sea level pressure. To specify the standard pressure to which the quantity applies, provide a scalar coordinate variable with standard name reference_pressure. M FVNLHC0H sea_surface_swell_wave_directional_spread The quantity with standard name sea_surface_swell_wave_directional_spread is the directional width of the swell wave component of a sea. Swell waves are waves on the ocean surface and are the low frequency portion of a bimodal wave frequency spectrum. Directional spread is the (one-sided) directional width within a given sub-domain of the wave directional spectrum, S(t,x,y,f,theta) where t is time, x and y are horizontal coordinates (such as longitude and latitude), f is frequency and theta is direction. For a given mean wave (beam) direction the quantity approximates half the root mean square width about the beam axis, as derived either directly from circular moments or via the Fourier components of the wave directional spectrum. I CVYXQSG3 biological_taxon_name "Biological taxon" is a name or other label identifying an organism or a group of organisms as belonging to a unit of classification in a hierarchical taxonomy. The quantity with standard name biological_taxon_name is the human-readable label for the taxon such as Calanus finmarchicus. The label should be registered in either WoRMS (http://www.marinespecies.org) or ITIS (https://www.itis.gov/) and spelled exactly as registered. See Section 6.1.2 of the CF convention (version 1.8 or later) for information about biological taxon auxiliary coordinate variables. I BBAH2106 change_over_time_in_sea_water_potential_density 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. Sea water potential density is the density a parcel of sea water would have if moved adiabatically to a reference pressure, by default assumed to be sea level pressure. To specify the reference pressure to which the quantity applies, provide a scalar coordinate variable with standard name reference_pressure. The density of a substance is its mass per unit volume. For sea water potential density, if 1000 kg m-3 is subtracted, the standard name "sea_water_sigma_theta" should be chosen instead. M CFSN0725 dimensionless_exner_function The term "Exner function" is applied to various quantities in the literature. "Dimensionless Exner function" is the standard name of (p/p0)^(R/Cp), where p is pressure, p0 a reference pressure, R the gas constant and Cp the specific heat at constant pressure. This quantity is also the ratio of in-situ to potential temperature. Standard names for other variants can be defined on request. To specify the reference pressure to which the quantity applies, provide a scalar coordinate variable with standard name reference_pressure. M HTBE8J95 tidal_sea_surface_height_above_mean_low_water_springs "Sea surface height" is a time-varying quantity. "Height_above_X" means the vertical distance above the named surface X. "Mean low water springs" describes a local vertical reference based on the time mean of the low water levels during spring tides (the tides each lunar month with the greatest difference between high and low water that happen during full and new moons phases) expected to occur under average meteorological conditions and under any combination of astronomical conditions. 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. I CFSN0333 sea_water_sigma_theta Sigma-theta of sea water is the potential density (i.e. the density when moved adiabatically to a reference pressure) of water having the same temperature and salinity, minus 1000 kg m-3. Note that sea water sigma is not the same quantity as the dimensionless ocean sigma coordinate (see Appendix D of the CF convention), for which there is another standard name. To specify the reference pressure to which the quantity applies, provide a scalar coordinate variable with standard name reference_pressure. M CFSN0542 mass_fraction_of_rain_in_air 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). D IECJ4WAM mass_fraction_of_rain_and_drizzle_in_air "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". Rain" means drops of water falling through the atmosphere that have a diameter greater than 0.5 mm. "Drizzle" means drops of water falling through the atmosphere that have a diameter typically in the range 0.2-0.5 mm. I DVE22M5G surface_direct_along_beam_shortwave_flux_in_air The surface called "surface" means the lower boundary of the atmosphere. "Direct" (also known as "beam") radiation is radiation that has followed a direct path from the sun and is alternatively known as "direct insolation". The phrase "along_beam" refers to direct radiation on a plane perpendicular to the direction of the sun. This is in contrast to standard names such as direct_downwelling_shortwave_flux_in_air, where the radiation falls on a horizontal plane at the earth surface. The term "shortwave" means shortwave radiation. In accordance with common usage in geophysical disciplines, "flux" implies per unit area, called "flux density" in physics. The quantity with standard name surface_direct_along_beam_shortwave_flux_in_air is also called Direct Normal Irradiance (DNI) in the solar energy industry. I T3IPUH1I colony_forming_unit_number_concentration_of_biological_taxon_in_sea_water "Colony forming unit" means an estimate of the viable bacterial or fungal numbers determined by counting colonies grown from a sample. "Number concentration" means the number of particles or other specified objects per unit volume. "Biological taxon" is a name or other label identifying an organism or a group of organisms as belonging to a unit of classification in a hierarchical taxonomy. There must be an auxiliary coordinate variable with standard name biological_taxon_name to identify the taxon in human readable format and optionally an auxiliary coordinate variable with standard name biological_taxon_identifier to provide a machine-readable identifier. See Section 6.1.2 of the CF convention (version 1.8 or later) for information about biological taxon auxiliary coordinate variables. I BBAD2159 atmosphere_mass_content_of_cloud_liquid_water "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. "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. M 434N7IWH atmosphere_mass_content_of_snow "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. "Snow" refers to the precipitating part of snow in the atmosphere – the cloud snow content is excluded. I YU6AEXR7 biological_taxon_identifier "Biological taxon" is a name or other label identifying an organism or a group of organisms as belonging to a unit of classification in a hierarchical taxonomy. The quantity with standard name biological_taxon_identifier is the machine-readable identifier for the taxon registration in either WoRMS (the AphiaID) or ITIS (the taxonomic serial number or TSN), including namespace. The namespace strings are 'aphia:' or 'tsn:'. For example, Calanus finmarchicus is encoded as either 'aphia:104464' or 'tsn:85272'. For the marine domain WoRMS has more complete coverage and so aphia Ids are preferred. See Section 6.1.2 of the CF convention (version 1.8 or later) for information about biological taxon auxiliary coordinate variables. I CFSN0543 mass_fraction_of_snow_in_air 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). "Snow" refers to the precipitating part of snow in the atmosphere – the cloud snow content is excluded. M