Why do trade winds blow consistently?
Show answer & explanation
Answer: Warm air rises at the equator and sinks at 30° latitude, with the return flow bent westward by Earth's spin
Warm air rises at the equator and sinks at 30° latitude, with the return flow bent westward by Earth's spin ✓ — Correct! This is the Hadley cell: rising equatorial air flows poleward aloft, sinks near 30°, and the surface return is deflected west by the Coriolis effect, giving the northeast trades in the Northern Hemisphere and southeast trades in the Southern.
The Moon's gravity pulls the air along a steady path around Earth — Wrong. The Moon's pull is far too weak to steer surface winds; it raises tides in the ocean, not steady trade winds.
Fast high-altitude jet streams dip down and drag surface air steadily toward the equator — Wrong. Jet streams are fast high-altitude westerlies; they don't dip down to drive the surface trade winds, which come from the Hadley circulation and Coriolis deflection.