Polar cells
Encyclopedia
Polar cells are part of a three-cell movement involving Hadley cell
Hadley cell
The Hadley cell, named after George Hadley, is a circulation pattern that dominates the tropical atmosphere, with rising motion near the equator, poleward flow 10–15 kilometers above the surface, descending motion in the subtropics, and equatorward flow near the surface...

s and Ferrel cells which show atmospheric circulation
Atmospheric circulation
Atmospheric circulation is the large-scale movement of air, and the means by which thermal energy is distributed on the surface of the Earth....

and surface winds.

Cold dense air descends over the poles, which creates high pressure; this cold air moves along the surface to lower latitudes. At around 60 degrees north and south, this air has been warmed up and rises upwards, creating a zone of low pressure.
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