- Air near equator is heated and rises until it hits the stratosphere where
- further heating ceases.
Air below pushes the stratospheric air outward, north and south.
Once air hits the stratosphere it continues cooling + flows north and south.
cools enough to begin to sink.
Asit sinks, warms and picks up water vapor, drying the environment.
This occurs around 30o and 60 latitude, north and south.(deserts)