What is the Tricellular Model

Refer to the diagram for easy understanding.

The Tricellular model is simply a chain showing the connections between 3 distinct cells namely the Hadley Cell, the Ferrel Cell and the Polar Cell. The origin of the Tricellular model is the equator extending outwards to the poles.

Hadley Cell

Air is heated at the equator and rises creating cumulonimbus clouds with heavy rain. The air continues outwards and descends at the 30^o South and North of the equator creating a subtropical HP (Ferrel cell). This is another factor causing the creation of deserts at the subtropical highs e.gSahara Desert

Polar Cell (LP)

Cold air from the poles converge and rises with the sub-tropical warm air creating a polar front with unstable conditions..

Ferrel Cell

This cell lies between the Hadley and the Polar cell. Raised air from the tropical and polar low pressure converge and descends at 30^o creating an area of high pressure with stable conditions.