tendency_of_air_temperature_due_to_boundary_layer_mixing

accepted
Created: Feb. 5, 2024
Proposer: Jonathan Gregory & Lars Barring
Proposed Date: 2024-01-10
#270
Change Date: Feb. 5, 2024, 4:45 p.m.
Term: tendency_of_air_temperature_due_to_boundary_layer_mixing
Unit: K s-1
Unit ref: KPRS
AMIP:
GRIB:
The phrase "tendency_of_X" means derivative of X with respect to time. Air temperature is the bulk temperature of the air, not the surface (skin) 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. "Boundary layer mixing" means turbulent motions that transport heat, water, momentum and chemical constituents within the atmospheric boundary layer and affect exchanges between the surface and the atmosphere. The atmospheric boundary layer is typically characterised by a well-mixed sub-cloud layer of order 500 metres, and by a more extended conditionally unstable layer with boundary-layer clouds up to 2 km. (Reference: IPCC Third Assessment Report, Working Group 1: The Scientific Basis, 7.2.2.3, https://archive.ipcc.ch/ipccreports/tar/wg1/273.htm).
Change Date: Feb. 5, 2024, 4:53 p.m.
Term: tendency_of_air_temperature_due_to_boundary_layer_mixing
Unit: K s-1
Unit ref: KPRS
AMIP:
GRIB:
The phrase "tendency_of_X" means derivative of X with respect to time. Air temperature is the bulk temperature of the air, not the surface (skin) 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. "Boundary layer mixing" means turbulent motions that transport heat, water, momentum and chemical constituents within the atmospheric boundary layer and affect exchanges between the surface and the atmosphere. The atmospheric boundary layer is typically characterised by a well-mixed sub-cloud layer of order 500 metres, and by a more extended conditionally unstable layer with boundary-layer clouds up to 2 km. (Reference: IPCC Third Assessment Report, Working Group 1: The Scientific Basis, 7.2.2.3, https://archive.ipcc.ch/ipccreports/tar/wg1/273.htm). It is strongly recommended to include a units_metadata attribute.
Change Date: Feb. 9, 2024, 3:49 p.m.
Term: tendency_of_air_temperature_due_to_boundary_layer_mixing
Unit: K s-1
Unit ref: KPRS
AMIP:
GRIB:
The phrase "tendency_of_X" means derivative of X with respect to time. Air temperature is the bulk temperature of the air, not the surface (skin) 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. "Boundary layer mixing" means turbulent motions that transport heat, water, momentum and chemical constituents within the atmospheric boundary layer and affect exchanges between the surface and the atmosphere. The atmospheric boundary layer is typically characterised by a well-mixed sub-cloud layer of order 500 metres, and by a more extended conditionally unstable layer with boundary-layer clouds up to 2 km. (Reference: IPCC Third Assessment Report, Working Group 1: The Scientific Basis, 7.2.2.3, https://archive.ipcc.ch/ipccreports/tar/wg1/273.htm). In order to convert the units correctly, it is essential to know whether a temperature is on-scale or a difference. Therefore this standard strongly recommends that any variable whose units involve a temperature unit should also have a units_metadata attribute to make the distinction. units_metadata="temperature: difference" means that the temperature quantity is the difference between two temperatures, so the origin of the scale is irrelevant, and only the unit of measure matters. It is strongly recommended to include the attribute units_metadata="temperature: difference".
Change Date: Feb. 23, 2024, 4:27 p.m.
Term: tendency_of_air_temperature_due_to_boundary_layer_mixing
Unit: K s-1
Unit ref: KPRS
AMIP:
GRIB:
The phrase "tendency_of_X" means derivative of X with respect to time. Air temperature is the bulk temperature of the air, not the surface (skin) 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. "Boundary layer mixing" means turbulent motions that transport heat, water, momentum and chemical constituents within the atmospheric boundary layer and affect exchanges between the surface and the atmosphere. The atmospheric boundary layer is typically characterised by a well-mixed sub-cloud layer of order 500 metres, and by a more extended conditionally unstable layer with boundary-layer clouds up to 2 km. (Reference: IPCC Third Assessment Report, Working Group 1: The Scientific Basis, 7.2.2.3, https://archive.ipcc.ch/ipccreports/tar/wg1/273.htm). It is strongly recommended that a variable with this standard name should have the attribute units_metadata="temperature: difference", meaning that it refers to temperature differences and implying that the origin of the temperature scale is irrelevant, because it is essential to know whether a temperature is on-scale or a difference in order to convert the units correctly (cf. https://cfconventions.org/cf-conventions/cf-conventions.html#temperature-units).