tendency_of_mass_fraction_of_stratiform_cloud_liquid_water_in_air_due_to_cloud_microphysics

complete
Created: Feb. 19, 2020
Proposer: Alison Pamment
Proposed Date: 2020-02-03
Change Date: Feb. 19, 2020, 1:24 p.m.
Term: tendency_of_mass_fraction_of_stratiform_cloud_liquid_water_in_air_due_to_cloud_microphysics
Unit: s-1
Unit ref: PRSC
AMIP:
GRIB:
The phrase "tendency_of_X" means derivative of X with respect to time. "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". In an atmosphere model, stratiform cloud is that produced by large-scale convergence (not the convection schemes). 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. "Cloud microphysics" is the sum of many cloud processes such as condensation, evaporation, homogeneous nucleation, heterogeneous nucleation, deposition, sublimation, the Bergeron-Findeisen process, riming, accretion, aggregation and icefall. The precise list of processes that are included in "cloud microphysics" can vary between models. Where possible, the data variable should be accompanied by a complete description of the processes included, for example, by using a comment attribute. Standard names also exist to describe the tendencies due to the separate processes.
Change Date: Feb. 19, 2020, 1:51 p.m.
Term: tendency_of_mass_fraction_of_stratiform_cloud_liquid_water_in_air_due_to_cloud_microphysics
Unit: s-1
Unit ref: PRSC
AMIP:
GRIB:
The phrase "tendency_of_X" means derivative of X with respect to time. "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". In an atmosphere model, stratiform cloud is that produced by large-scale convergence (not the convection schemes). "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. 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. "Cloud microphysics" is the sum of many cloud processes such as condensation, evaporation, homogeneous nucleation, heterogeneous nucleation, deposition, sublimation, the Bergeron-Findeisen process, riming, accretion, aggregation and icefall. The precise list of processes that are included in "cloud microphysics" can vary between models. Where possible, the data variable should be accompanied by a complete description of the processes included, for example, by using a comment attribute. Standard names also exist to describe the tendencies due to the separate processes.