Why are deserts so dry?
Show answer & explanation
Answer: Air that rises at the equator and sinks near 30° latitude
Air that rises at the equator and sinks near 30° latitude ✓ — Correct! Most deserts form around 30° latitude, where air that rose at the equator has cooled, sunk back down and warmed as it falls. Warm sinking air cannot form rain clouds, so places like the Sahara, Arabian and Australian deserts stay arid.
Too much sun evaporates water before rain can fall — Wrong. Evaporation is high in deserts, but it is a result of the dry air, not the cause. Deserts exist mainly because sinking air prevents rain clouds from forming in the first place.
Sand absorbs all moisture before it can reach the ground — Wrong. Sand does not soak up moisture from the air to create deserts. Deserts form because sinking air keeps rain clouds from forming, not because of what the ground is made of.