Deserts

Deserts receive less than 25 cm of precipitation annually and form in four main regions: subtropics, rain shadow areas, regions with cold ocean currents, and polar regions. Subtropical deserts like the Sahara form due to dry air from the equator. Rain shadow deserts, such as the Gobi, are shielded by mountains. Cold ocean currents create deserts like the Atacama by cooling air and causing rain before clouds reach land. Polar deserts, like Antarctica, form due to extreme cold freezing water vapor. Despite differences, all deserts are characterized by dryness.

What role do cold ocean currents play in the formation of deserts?

Describe the characteristics that make Antarctica the largest desert in the world.