Climate and Forecast Standard Names
type: ConceptScheme
has top concept: lagrangian_tendency_of_air_pressure

lagrangian_tendency_of_air_pressure
type: Concept
top concept of: Climate and Forecast Standard Names
source: cf-standard-name-table.html
replaces: vertical air velocity expressed as tendency of pressure
replaces: omega
definition: "tendency_of_X" means derivative of X with respect to time. The Lagrangian tendency of a quantity is its rate of change following the motion of the fluid, also called the "material derivative" or "convective derivative". The Lagrangian tendency of air pressure, often called "omega", plays the role of the upward component of air velocity when air pressure is being used as the vertical coordinate. If the vertical air velocity is upwards, it is negative when expressed as a tendency of air pressure; downwards is positive. 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.
note: Mapping to be determined
in scheme: Climate and Forecast Standard Names