6.1.2—Atmospheric circulation
- Syllabus
- First assessment 2026
- Objective
- 6.1.2
- Level
- HL
Move Heat Away from the Equator
Unequal solar heating creates pressure and temperature contrasts; rising, sinking and rotating air redistribute energy through idealized Hadley, Ferrel and Polar cells.
Warm air expands and rises, cool air sinks, and pressure gradients move air. The cells help explain wind and rainfall belts, but they do not erase temperature differences.
More direct equatorial sunlight warms air that rises and transports energy poleward aloft before descending elsewhere.
To explain broad circulation and energy transport, not predict every local wind or storm.
The three-cell model is idealized; mountains, seasons and oceans modify real circulation.