Proposals for CF

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68 proposals match your search

river_channel_storage

under discussion
Proposer: Dikra Khedhaouiria
Proposed Date: Oct. 6, 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_4_in_sea_water

under discussion
Proposer: Fernando Carvalho Pacheco & Fernando Santiago-Mandujano & Karin Bjorkman & Andrew Barna
Proposed Date: Oct. 19, 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.

mass_concentration_of_phycoerythrin_5_in_sea_water

under discussion
Proposer: Fernando Carvalho Pacheco & Fernando Santiago-Mandujano & Karin Bjorkman & Andrew Barna
Proposed Date: Oct. 19, 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.

mass_concentration_of_phycoerythrin_10_in_sea_water

under discussion
Proposer: Fernando Carvalho Pacheco & Fernando Santiago-Mandujano & Karin Bjorkman & Andrew Barna
Proposed Date: Oct. 19, 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.

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: Oct. 19, 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.

number_size_distribution_of_aerosol_particles_at_stp_in_air

under discussion
Proposer: Markus Fiebig
Proposed Date: Sept. 22, 2021
Comments: #127
Units: PCUM (m-3)
New Term
The aerosol particle number size distribution is the number concentration of aerosol particles as a function of particle diameter. A coordinate variable with the standard name of electrical_mobility_particle_diameter, aerodynamic_particle_diameter, or optical_particle_diameter should be specified to indicate that the property applies at specific particle sizes selected by the indicated method. To specify the relative humidity at which the particle sizes were selected, provide a scalar coordinate variable with the standard name of relative_humidity_for_aerosol_particle_size_selection. "log10_X" means common logarithm (i.e. base 10) of X. "stp" means standard temperature (0 degC) and pressure (101325 Pa).

number_size_distribution_of_cloud_condensation_nuclei_in_air

under discussion
Proposer: Markus Fiebig
Proposed Date: Sept. 22, 2021
Comments: #127
Units: m-3 (PCUM)
New Term
The cloud condensation nuclei number size distribution is the number concentration of aerosol particles as a function of particle diameter, where the particle acts as condensation nucleus for liquid-phase clouds. A coordinate variable with the standard name of relative_humidity should be specified to indicate that the property refers to a specific supersaturation with respect to liquid water. A coordinate variable with the standard name of electrical_mobility_particle_diameter should be specified to indicate that the property applies at specific mobility particle sizes. To specify the relative humidity at which the particle sizes were selected, provide a scalar coordinate variable with the standard name of relative_humidity_for_aerosol_particle_size_selection. The ability of a particle to act as a condensation nucleus is determined by its size, chemical composition, and morphology.

log10_size_interval_based_number_size_distribution_of_cloud_condensation_nuclei_in_air

under discussion
Proposer: Markus Fiebig
Proposed Date: Sept. 22, 2021
Comments: #127
Units: m-3 (PCUM)
New Term
The cloud condensation nuclei number size distribution is the number concentration of aerosol particles, normalised to the decadal logarithmic size interval the concentration applies to, as a function of particle diameter, where the particle acts as condensation nucleus for liquid-phase clouds. A coordinate variable with the standard name of relative_humidity should be specified to indicate that the property refers to a specific supersaturation with respect to liquid water. A coordinate variable with the standard name of electrical_mobility_particle_diameter should be specified to indicate that the property applies at specific mobility particle sizes. To specify the relative humidity at which the particle sizes were selected, provide a scalar coordinate variable with the standard name of relative_humidity_for_aerosol_particle_size_selection. The ability of a particle to act as a condensation nucleus is determined by its size, chemical composition, and morphology. "log10_X" means common logarithm (i.e. base 10) of X.

log10_size_interval_based_number_size_distribution_of_aerosol_particles_at_stp_in_air

under discussion
Proposer: Markus Fiebig
Proposed Date: Sept. 22, 2021
Comments: #127
Units: m-3 (PCUM)
New Term
The aerosol particle number size distribution is the number concentration of aerosol particles, normalised to the decadal logarithmic size interval the concentration applies to, as a function of particle diameter. A coordinate variable with the standard name of electrical_mobility_particle_diameter, aerodynamic_particle_diameter, or optical_particle_diameter should be specified to indicate that the property applies at specific particle sizes selected by the indicated method. To specify the relative humidity at which the particle sizes were selected, provide a scalar coordinate variable with the standard name of relative_humidity_for_aerosol_particle_size_selection. "log10_X" means common logarithm (i.e. base 10) of X. "stp" means standard temperature (0 degC) and pressure (101325 Pa).

log10_size_interval_based_number_size_distribution_of_aerosol_particles_in_air

under discussion
Proposer: Markus Fiebig
Proposed Date: Sept. 22, 2021
Comments: #127
Units: m-3 (PCUM)
New Term
The aerosol particle number size distribution is the number concentration of aerosol particles, normalised to the decadal logarithmic size interval the concentration applies to, as a function of particle diameter. A coordinate variable with the standard name of electrical_mobility_particle_diameter, aerodynamic_particle_diameter, or optical_particle_diameter should be specified to indicate that the property applies at specific particle sizes selected by the indicated method. To specify the relative humidity at which the particle sizes were selected, provide a scalar coordinate variable with the standard name of relative_humidity_for_aerosol_particle_size_selection. "log10_X" means common logarithm (i.e. base 10) of X.

number_size_distribution_of_cloud_condensation_nuclei_at_stp_in_air

under discussion
Proposer: Markus Fiebig
Proposed Date: Sept. 22, 2021
Comments: #127
Units: m-3 (PCUM)
New Term
The cloud condensation nuclei number size distribution is the number concentration of aerosol particles as a function of particle diameter, where the particle acts as condensation nucleus for liquid-phase clouds. A coordinate variable with the standard name of relative_humidity should be specified to indicate that the property refers to a specific supersaturation with respect to liquid water. A coordinate variable with the standard name of electrical_mobility_particle_diameter should be specified to indicate that the property applies at specific mobility particle sizes. To specify the relative humidity at which the particle sizes were selected, provide a scalar coordinate variable with the standard name of relative_humidity_for_aerosol_particle_size_selection. The ability of a particle to act as a condensation nucleus is determined by its size, chemical composition, and morphology. "stp" means standard temperature (0 degC) and pressure (101325 Pa).

number_size_distribution_of_aerosol_particles_in_air

under discussion
Proposer: Markus Fiebig
Proposed Date: Sept. 22, 2021
Comments: #127
Units: PCUM (m-3)
New Term
The aerosol particle number size distribution is the number concentration of aerosol particles as a function of particle diameter. A coordinate variable with the standard name of electrical_mobility_particle_diameter, aerodynamic_particle_diameter, or optical_particle_diameter should be specified to indicate that the property applies at specific particle sizes selected by the indicated method. To specify the relative humidity at which the particle sizes were selected, provide a scalar coordinate variable with the standard name of relative_humidity_for_aerosol_particle_size_selection.

volume_backscatter_radiation_spectralwidth_in_air_of_instrument

new
Proposer: Ingemar Häggström
Proposed Date: Oct. 1, 2021
Comments:
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.

radial_velocity_of_scatterers_away_from_instrument

new
Proposer: Ingemar Häggström
Proposed Date: Oct. 1, 2021
Comments:
Units: m s-1 (UVAA)
New Term
A velocity is a vector quantity. "Radial velocity away from instrument" means the component of the velocity along the line of sight of the instrument where positive implies movement away from the instrument (i.e. outward). 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 radial velocity "toward_instrument" should be used for a data variable having the opposite sign convention.

volume_backscatter_radiation_roundtrip_travel_time_in_air_of_instrument

new
Proposer: Ingemar Häggström
Proposed Date: Oct. 1, 2021
Comments:
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.

volume_backscatter_of_radiation_power_in_air_of_instrument

new
Proposer: Ingemar Häggström
Proposed Date: Oct. 1, 2021
Comments:
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.

number_concentration_of_cloud_condensation_nuclei_in_air

new
Proposer: Markus Fiebig
Proposed Date: Sept. 22, 2021
Comments:
Units: m-3 (PCUM)
New Term
The cloud condensation nuclei number concentration is the total number of aerosol particles per unit volume independent of and integrated over particle size that act as condensation nuclei for liquid-phase clouds. A coordinate variable with the standard name of relative_humidity should be specified to indicate that the property refers to a specific supersaturation with respect to liquid water. The ability of a particle to act as a condensation nucleus is determined by its size, chemical composition, and morphology.

number_concentration_of_aerosol_particles_in_air

new
Proposer: Markus Fiebig
Proposed Date: Sept. 22, 2021
Comments:
Units: m-3 (PCUM)
New Term
"Number concentration" means the number of particles or other specified objects per unit volume. "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself.

mole_fraction_of_methane_in_dry_air

under discussion
Proposer: Claudio D'Onofrio
Proposed Date: Sept. 6, 2021
Comments: ENVRI-FAIR
"Mole fraction" is used in the construction "mole_fraction_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 "in_dry_air" means that the quantity is calculated as the number of particles of X divided by the number of dry air particles, i.e. the effect of water vapor is excluded. The chemical formula for methane is CH4. Methane is a member of the group of hydrocarbons known as alkanes. There are standard names for the alkane group as well as for some of the individual species.

mole_fraction_of_carbon_monoxide_in_dry_air

under discussion
Proposer: Claudio D'Onofrio
Proposed Date: Sept. 6, 2021
Comments: ENVRI-FAIR
"Mole fraction" is used in the construction "mole_fraction_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 "in_dry_air" means that the quantity is calculated as the total number of particles of X divided by the number of dry air particles, i.e. the effect of water vapor is excluded. The chemical formula of carbon monoxide is CO.

mole_fraction_of_carbon_dioxide_in_dry_air

under discussion
Proposer: Claudio D'Onofrio
Proposed Date: Sept. 6, 2021
Comments: ENVRI-FAIR
"Mole fraction" is used in the construction "mole_fraction_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 "in_dry_air" means that the quantity is calculated as the total number of particles of X divided by the number of dry air particles, i.e. the effect of water vapor is excluded. The chemical formula for carbon dioxide is CO2.

mole_fraction_of_nitrogen_dioxide_in_dry_air

under discussion
Proposer: Claudio D'Onofrio
Proposed Date: Sept. 6, 2021
Comments: ENVRI-FAIR
"Mole fraction" is used in the construction "mole_fraction_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 chemical formula for nitrogen dioxide is NO2.

northward_storm_velocity

under discussion
Proposer: Emily Schlie, Eric Engle, and the CAMPS team (NOAA MDL)
Proposed Date: Dec. 22, 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: Dec. 22, 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: May 20, 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_period_at_variance_spectral_density_maximum

new
Proposer:
Proposed Date: None
Comments:
CF mailing list link:
Units: s (UTBB)
Updated term description
A period is an interval of time, or the time-period of an oscillation. The sea_surface_wave_period_at_variance_spectral_density_maximum, sometimes called peak wave period, is the period of the most energetic waves in the total wave spectrum at a specific location. 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 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. The density of a substance is its mass per unit volume. 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.

sea_surface_wave_variance_spectral_density_attenuation_coefficient_due_to_icebergs

under discussion
Proposer: Andy Saulter
Proposed Date: Dec. 21, 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.

air_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. Air temperature is the bulk temperature of the air, not the surface (skin) temperature. To specify the reference (baseline) epoch to which the quantity applies, provide a scalar coordinate variable with standard name reference_epoch.

brightness_temperature_anomaly

new
Proposer:
Proposed Date: None
Comments:
CF mailing list link:
Units: K (UPKA)
Updated term description
The brightness temperature of a body is the temperature of a black body which radiates the same power per unit solid angle per unit area. The term "anomaly" means difference from climatology. To specify the reference (baseline) epoch to which the quantity applies, provide a scalar coordinate variable with standard name reference_epoch.

air_pressure_anomaly

new
Proposer:
Proposed Date: None
Comments:
CF mailing list link:
Units: Pa (PASX)
Updated term description
The term "anomaly" means difference from climatology. Air pressure is the force per unit area which would be exerted when the moving gas molecules of which the air is composed strike a theoretical surface of any orientation. To specify the reference (baseline) epoch to which the quantity applies, provide a scalar coordinate variable with standard name reference_epoch.

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.

geopotential_height_anomaly

new
Proposer:
Proposed Date: None
Comments:
CF mailing list link:
Units: m (ULAA)
Updated term description
The term "anomaly" means difference from climatology. Geopotential is the sum of the specific gravitational potential energy relative to the geoid and the specific centripetal potential energy. Geopotential height is the geopotential divided by the standard acceleration due to gravity. It is numerically similar to the altitude (or geometric height) and not to the quantity with standard name height, which is relative to the surface. To specify the reference (baseline) epoch to which the quantity applies, provide a scalar coordinate variable with standard name reference_epoch.

ratio_of_sea_water_potential_temperature_anomaly_to_relaxation_timescale

new
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. To specify the reference (baseline) epoch to which the quantity applies, provide a scalar coordinate variable with standard name reference_epoch.

ratio_of_sea_water_practical_salinity_anomaly_to_relaxation_timescale

new
Proposer:
Proposed Date: None
Comments:
CF mailing list link:
Units: s-1 (PRSC)
Updated term description
The quantity with standard name ratio_of_sea_water_practical_salinity_anomaly_to_relaxation_timescale is a correction term applied to modelled sea water practical salinity. The term is estimated as the deviation of model local sea water practical salinity from an observation-based climatology (e.g. World Ocean Database) weighted by a user-specified relaxation coefficient in s-1 (1/(relaxation timescale)). The phrase "ratio_of_X_to_Y" means X/Y. The term "anomaly" means difference from climatology. Practical Salinity, S_P, is a determination of the salinity of sea water, based on its electrical conductance. The measured conductance, corrected for temperature and pressure, is compared to the conductance of a standard potassium chloride solution, producing a value on the Practical Salinity Scale of 1978 (PSS-78). This name should not be used to describe salinity observations made before 1978, or ones not based on conductance measurements. Conversion of Practical Salinity to other precisely defined salinity measures should use the appropriate formulas specified by TEOS-10. Other standard names for precisely defined salinity quantities are sea_water_absolute_salinity (S_A); sea_water_preformed_salinity (S_*), sea_water_reference_salinity (S_R); sea_water_cox_salinity (S_C), used for salinity observations between 1967 and 1977; and sea_water_knudsen_salinity (S_K), used for salinity observations between 1901 and 1966. Salinity quantities that do not match any of the precise definitions should be given the more general standard name of sea_water_salinity. Reference: www.teos-10.org; Lewis, 1980 doi:10.1109/JOE.1980.1145448. To specify the reference (baseline) epoch to which the quantity applies, provide a scalar coordinate variable with standard name reference_epoch.

lwe_solid_precipitation_rate

under discussion
Proposer: Yuling Wu
Proposed Date: Aug. 6, 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.

surface_roughness_length_due_to_vegetation

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

mass_concentration_of_pm10_calcium_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: June 29, 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_potassium_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: June 29, 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_magnesium_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: June 29, 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_nitrate_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: June 29, 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_sulfate_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: June 29, 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_ammonium_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: June 29, 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_methanesulfonic_acid_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: June 29, 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_sodium_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: June 29, 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_oxalate_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: June 29, 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-).

mass_concentration_of_pm10_chloride_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: June 29, 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_bromide_dry_aerosol_particles_in_air

under discussion
Proposer: Jen Thomas and Christian Tatzelt
Proposed Date: June 29, 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-.

lake_water_temperature

new
Proposer: Beate Geyer and Burkhardt Rockel
Proposed Date: Aug. 21, 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: Aug. 21, 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.

lake_mixed_layer_thickness

new
Proposer: Beate Geyer and Burkhardt Rockel
Proposed Date: Aug. 21, 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.

downward_heat_flux_at_snow_base

new
Proposer: Martin Jukes
Proposed Date: May 13, 2020
Comments:
Units: W m-2 (UFAA)
New Term
"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.

upward_geothermal_heat_flux_at_ground_level_in_land_ice

new
Proposer: Martin Jukes
Proposed Date: Sept. 30, 2019
Comments:
Units: W m-2 (UFAA)
Updated term description
"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_geothermal_heat_flux_at_ground_level_in_land_ice 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.

potential_vorticity_of_atmosphere_layer

new
Proposer: Beate Geyer
Proposed Date: March 11, 2020
Comments:
Units: Pa-1 s-1 (PPPS)
Updated term description
"Layer" means any layer with upper and lower boundaries that have constant values in some vertical coordinate. There must be a vertical coordinate variable indicating the extent of the layer(s). If the layers are model layers, the vertical coordinate can be model_level_number, but it is recommended to specify a physical coordinate (in a scalar or auxiliary coordinate variable) as well. Atmosphere potential vorticity is the vertically averaged absolute vorticity of a layer of the atmosphere divided by the pressure difference from the bottom to the top of the layer.

surface_shortwave_dust_ambient_aerosol_direct_radiative_effect

under discussion
Proposer: Martin Juckes
Proposed Date: April 24, 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_assuming_clear_sky

under discussion
Proposer: Martin Juckes
Proposed Date: April 24, 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.

toa_longwave_dust_ambient_aerosol_direct_radiative_effect_assuming_clear_sky

under discussion
Proposer: Martin Juckes
Proposed Date: April 24, 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_shortwave_dust_ambient_aerosol_direct_radiative_effect_assuming_clear_sky

under discussion
Proposer: Martin Juckes
Proposed Date: April 24, 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_longwave_dust_ambient_aerosol_direct_radiative_effect

under discussion
Proposer: Martin Juckes
Proposed Date: April 24, 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.

surface_downward_turbulent_heat_flux

under discussion
Proposer: Martin Juckes / Alison Pamment
Proposed Date: July 4, 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.

upward_turbulent_heat_flux_in_air

under discussion
Proposer: Martin Juckes / Alison Pamment
Proposed Date: July 4, 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.

integral_wrt_time_of_surface_downward_turbulent_heat_flux

under discussion
Proposer: Martin Juckes / Alison Pamment
Proposed Date: July 4, 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.

surface_upward_turbulent_heat_flux

under discussion
Proposer: Martin Juckes / Alison Pamment
Proposed Date: July 4, 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.

isotope_ratio_of_2H_to_1H_in_sea_water_excluding_solutes_and_solids

under discussion
Proposer: Martin Juckes
Proposed Date: April 3, 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: Feb. 23, 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: May 18, 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: May 18, 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: Jan. 19, 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: Jan. 19, 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.