Editing Fundamentals of Meteorology (section)

== The Coriolis Effect and Prevailing Winds ==

As the circulation cells move air north and south, the rotation of the Earth fundamentally alters their path. Because the Earth is a rotating sphere, the equator spins much faster (roughly 1,000 mph) than the poles (near 0 mph). As air moves across these differing rotational speeds, its path appears to curve relative to the surface. 

This phenomenon is known as the '''Coriolis Effect'''. It deflects moving air to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. The combination of the surface air movements within the three circulation cells and the deflection of the Coriolis effect creates Earth's major '''prevailing winds'''.

* '''The Trade Winds:''' In the Hadley cell, surface air flows from the 30-degree high-pressure zones back toward the equator. The Coriolis effect deflects this air westward. These reliable, steady easterly winds (blowing from east to west) are known as the Trade Winds.
* '''The Westerlies:''' In the Ferrel cell, surface air moves poleward from 30 degrees to 60 degrees. The Coriolis effect deflects this air eastward. These winds, blowing from west to east, dominate the mid-latitudes and drive the weather systems across North America and Europe.
* '''The Polar Easterlies:''' In the Polar cell, cold surface air moves equatorward from the poles. Deflected westward by the Coriolis effect, these winds blow from the east, bringing frigid polar air into the upper mid-latitudes.

Understanding these circulation patterns is crucial for meteorology, as they dictate global precipitation distribution, govern ocean surface currents, and determine the pathways of major storm systems across the planet.