a stable heat engine that dissipates thermal imbalances by generating local instabilities (eddies).
Atmospheric Energy cycle
Total potential energy converted to kinetic energy and subsequently destroy by friction.
Available Potential Energy
The difference between the potential energy of an atmospheric column and that of its base state (i.e., mean state of the atmosphere)
adiabatic equilibrium (i.e., no thermal gradients exist on an isobaric surface)
Atmospheric motion is produced by thermal gradient
not the actual temp
Ascent of warm air or descent of cold air
descent of warm air or ascent of cold
eddy (wave) component
corresponds to thermal and wind speed variations along a latitude circle
varies latitudinally (north south)
zonal available potential energy
The meridional temp gradient (temp change along a line of longitude), is caused by differential heating of the earth's surface.
principal internal energy conversion
between zonal and eddy availible potential energy, and between eddy availible potential energy and eddy kinetic energy.
This stage may also involve large stationary or retrograding eddies
characterized by large waves (ridges/troughs)
Equivalent Barotropic Atmosphere
Conditions in which there is a temperature gradient,but isotherms are parallel to the isobars (geopotential height contours). The thermal wind exists,but it can only alter the geostrophic wind speed, not the direction of the geostrophic wind. Seebaroclinic atmosphere, barotropic atmosphere, thermal wind
Tradeoff of relative vorticity and coriolis along a line of constant absolute vorticity
Conditions in which there may be a pressure (geopotential height) gradient, but no temperature gradient in the atmosphere. See baroclinic atmosphere,equivalent barotropic atmosphere, thermal wind
Winds are unidirectional and increase speed with height.
No thermal advections
Temp gradients along constant pressure surfaces.
tilted pressure trough with height
migratory cyclones and frontal zones
Difference between the UL and LL geostrophic wind
difference between the UL and LL vorticity
Measures the mean strength of the mid-lat zonal geostrophic wind.