Tri-cellular model of atmospheric circulation & Pressure belts of the world

Published on 31 Jan 2025

The Tri-cellular model of atmospheric circulation is a simplified representation of the global atmospheric circulation patterns, divided into three major cells in each hemisphere: the Hadley cell, Ferrel cell, and Polar cell. These cells play a crucial role in redistributing heat and moisture around the Earth.

• Hadley Cell: Near the equator, warm air rises, creating a low-pressure zone.

• Ferrel Cell: Mid-latitudes, between approximately 30° and 60°. The descending air from the Hadley cell creates high pressure at around 30° latitude.

• Polar cells: At the poles, the polar cell involves rising air. This air cools and descends at around 60° latitude, creating high pressure.

Pressure belts of the world

• Equatorial low-pressure belt / doldrums: Formed around the equator (0°). Low pressure due to intense solar heating, leading to rising warm, moist air, and convergence of trade winds. Area receives heavy precipitation with calm winds.

• Subtropical Highs pressure belt / Horse latitude: Located around 30° latitude. High pressure due to descending air from the Hadley cell, creating stable conditions. They bring heavy precipitation to western coast. 

• Sub -Polar Low-Pressure Belt: Formed around 60° latitude. Low pressure caused by the convergence of polar easterlies and westerlies. Associated with stormy weather and the polar front.

• Polar high-pressure belt: Formed around Polar Regions (90°). High pressure due to descending cold air from the polar cell, creating stable conditions. Associated with polar easterlies.

Tags:
Geography

Keywords:
Tri-cellular model of atmospheric circulation & Pressure belts of the world adley cell Ferrel cell Polar cell pressure belts

Syllabus:
General Studies Paper 1

Topics:
Physical Geography