Hi,
Here are a few requests for new standard_name attribute values. Most of these are
variants of existing names, new species for constructs that already exist, some will
require more iterations.
In the second half I've put a reminder for some names I've submitted before, but have
not been included at this moment. The last item is an interpretation question.
height_at_center_of_aerosol_layer:
Height is the vertical distance above the surface. The center corresponds to the
height corresponding to the mean air pressure of the top and bottom of the layer
containing aerosol particles.
Canonical unit: m
air_pressure_at_center_of_aerosol_layer:
(Air pressure is not specified further within the CF standard name table). The
center corresponds to the mean air pressure of the top and bottom of the layer
containing aerosol particles.
Canonical unit: Pa
dry_atmosphere_mole_fraction_of_methane
Mole fraction is used in the construction "mole_fraction_of_X_in_Y", where X is
a material constituent of Y. A chemical species denoted by X may be described by a
single term such as "nitrogen" or a phrase such as "nox_expressed_as_nitrogen". The
construction "dry_atmosphere_mole_fraction" means that the quantity refers to the
whole atmospheric column and is calculated as the total number of particles of X in
the column divided by the number of dry air particles in the same column, i.e. the
effect of water vapor is excluded. For localized values within the atmospheric
medium, standard names including "in_air" are used. The chemical formula for methane
is CH4.
Canonical unit: 1
atmosphere_mole_content_of_carbon_monoxide:
"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 carbon monoxide is CO.
Canonical unit: mol m-2
atmosphere_mole_content_of_water_vapor:
"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 water vapor is H2O.
Canonical unit: mol m-2
surface_upwelling_shortwave_flux_in_air_due_to_fluorescence:
The surface called "surface" means the lower boundary of the atmosphere.
"shortwave" means shortwave radiation. Upwelling radiation is radiation from below.
It does not mean "net upward". 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. 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. The fluorescence is caused by chlorophyll.
Canonical unit: mol s-2 m-2 m-1 sr-1
(Note: do not simplify the unit to mol s-2 m-3 sr-1, the first is a surface
area, the second is a radiation wavelength).
atmosphere_mole_content_of_methane:
"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 methane is CH4.
Canonical unit: mol m-2
atmosphere_mole_content_of_semiheavy_water_vapor:
"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 semiheavy or deuterated water vapor is HDO.
(Note: I use semiheavy_water here to leave room for heavy_water)
Canonical unit: mol m-2
height_of_cloud_optical_centroid:
The cloud height at optical centriod is a height within the cloud, near the
optical thickness center of the cloud. See also: air_pressure_at_cloud_optical_centroid.
Canonical unit: m
atmosphere_mole_content_of_nitrogen_dioxide:
"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 chemical formula for
nitrogen_dioxide is NO2.
Canonical unit: mol m-2
air_temperature_at_150cm:
Air temperature is the bulk temperature of the air, not the surface (skin)
temperature. This is the 1.5 m height at which synoptic observations are performed.
(Note: oddly enough I coun't find this parameter in the list. I use 150 cm to
avoid using a dot in a standard name value).
Canonical unit: K
air_temperature_at_cloud_optical_centroid:
Air temperature is the bulk temperature of the air, not the surface (skin)
temperature. The cloud optical centriod pressure is a pressure level inside the
cloud, near the optical thickness center of the cloud. See also:
air_pressure_at_cloud_optical_centroid.
Canonical unit: K
* The following names were submitted before, but do not yet appear in the
standard_name table, this serves as a reminder, using the latest reply on the list as
a starting point. See the thread with subject "New standard_name values for some
cloud and aerosol related variables" started by me on 30 September 2015:
ultraviolet_aerosol_index:
ultraviolet means ultraviolet radiation, with wavelengths shorter than 400 nm.
The UV-Aerosol Index is a UV color index that represents the deviation of the
outgoing TOA radiation in the UV from that of a standard atmosphere, featuring
Rayleigh scattering and gas absorption, in particular by ozone. No cloud droplets or
suspended liquid or solid particles (aerosols) are present in the standard
atmosphere. It is bounded below by a Lambertian surface, featuring isotropic
reflection, assumed independent of wavelength. The ultraviolet aerosol index is
computed from the Earth reflectances at two UV wavelengths. A positive deviation from
the standard atmosphere is often, but not exclusively, attributed to the absorption
of radiation by aerosols, while negative values represent increased scattering, not
necessarily by aerosols. The wavelengths used for the computation of the ultraviolet
aerosol index should be indicated using a coordinate variable with standard name
radiation _wavelength and length 2. This support coordinate variable should be given
in the ancillary_variables attribute.
(Note: not the coordinates attribute, as this is an annotation, not a
coordinate).
Canonical unit: 1
air_pressure_at_cloud_optical_centroid:
The cloud optical centriod pressure is a pressure level inside the cloud, near
the optical thickness center of the cloud.
Canonical unit: Pa
effective_cloud_area_fraction_assuming_fixed_cloud_albedo:
"X_area_fraction" means the fraction of horizontal area occupied by X. "X_area"
means the horizontal area occupied by X within the grid cell or the satellite
footprint. Cloud area fraction is also called "cloud amount" and "cloud cover". The
cloud area fraction is for the whole atmosphere column, as seen from the surface or
the top of the atmosphere. Cloud area fraction assuming fixed cloud albedo is the
cloud area fraction by assuming the clouds in the X_area having the same fixed cloud
albedo value (Y). The clouds having cloud_area_fraction_assuming_fixed_cloud_albedo
and cloud albedo Y yield the same reflectance at TOA as the real clouds in the
X_area. 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. The assumed albedo shall
be attached to the variable either by an attribute 'assumed_cloud_albedo' (if the
value is independent of geolocation) or through the ancillary_variables to a variable
with standard_name 'cloud_albedo'.
Canonical unit: 1
cloud_albedo_assuming_completely_cloudy_sky
cloud_albedo_assuming_completely_cloudy_sky means a derived (retrieved) cloud
albedo in an area assuming the scene is completely cloud covered (the grid cell or
satellite footprint). 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.
Canonical unit: 1
air_pressure_at_cloud_optical_centroid_assuming_completely_cloudy_sky
The cloud optical centriod pressure is a pressure level inside the cloud, near
the optical thickness center of the cloud.
air_pressure_at_cloud_optical_centroid_assuming_completely_cloudy_sky means a cloud
optical centriod pressure assuming the scene is completely cloud covered (the grid
cell or satellite footprint). 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.
Canonical unit: Pa
* The following names are close, but not close enough for our purposes:
atmosphere_optical_thickness_due_to_ambient_aerosol_particles:
The optical thickness is the integral along the path of radiation of a volume
scattering/absorption/attenuation coefficient. The radiative flux is reduced by a
factor exp(-optical_thickness) on traversing the path. A coordinate variable of
radiation_wavelength or radiation_frequency can be specified to indicate that the
optical thickness applies at specific wavelengths or frequencies. The atmosphere
optical thickness applies to radiation passing through the entire atmosphere.
"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. "Ambient aerosol
particles" are aerosol particles that have taken up ambient water through hygroscopic
growth. The extent of hygroscopic growth depends on the relative humidity and the
composition of the particles. To specify the relative humidity and temperature at
which the quantity described by the standard name applies, provide scalar coordinate
variables with standard names of "relative_humidity" and "air_temperature". 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.
(Note: The description seems to indicate a slant path, not a vertical path. We
need the latter, which also seems to be more appropriate for modellers. Any
suggestions for a new name and full description?)
Canonical unit: 1
Thank you for reading this far.
Maarten Sneep
--
KNMI
T: 030 2206747
E: [email protected]
R: A2.14
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