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Baroclinic instability leads to eddy formation. While there is a mid-latitude convective cell, its importance to heat transport is dwarfed by these eddies, which stir heat from the equator towards the pole. Eddy heat transport is horizontal, in contrast to the convective overturning at lower latitudes, and so varies less with height. The mid-latitude region dominated by weather systems extends from 30° to 60° N and S, where it gives way to the polar convective cell.
The seasonal variation and heat transport capacity of the Hadley and mid-latitude regimes can be demonstrated by examining data from the atmosphere.
General Circulation in the Atmosphere
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Fast Rotation Experiment
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