Ferrel cell
Topic: Atmospheric Pressure, Winds and General Circulation · NCERT: Class 11, Ch 9 "Atmospheric Circulation and Weather Systems"
Meaning
The Ferrel cell is the middle-latitude loop of air between about 30° and 60° latitude, in each hemisphere. Near the ground, air flows towards the poles. The Coriolis force (a turning effect caused by the Earth's spin) bends this air into the westerlies. The cell is thermally indirect: direct heating does not drive it. The Hadley cell on one side and the polar cell on the other turn it, like a gear between two gears. William Ferrel described it in 1856. In real weather, travelling cyclones and anticyclones carry most of the heat across these latitudes.
Example
North-west Europe, including Britain, lies under the Ferrel cell. Its surface westerlies bring mild, rainy weather from the Atlantic all year.
Don't confuse with
- Hadley cell: a direct thermal cell between 0° and 30°. Air rises at the equator because the Sun heats it strongly, and the surface winds are the trade winds, not the westerlies.