GED Science TestEarth and Space ScienceMedium
A climatologist is analyzing long-term climate data for a desert region located around 30 degrees latitude. They observe that this region consistently experiences high atmospheric pressure, clear skies, and very little precipitation. Which atmospheric circulation cell is primarily responsible for these climatic conditions?
- APolar Cell
- BWalker Circulation
- CHadley Cell
- DFerrel Cell
Show answer & explanationAnswer & explanation
Correct answer: C. Hadley Cell
The Hadley Cell is responsible for the atmospheric circulation between the equator and approximately 30 degrees latitude. Warm, moist air rises at the equator, moves poleward, cools, and then descends around 30 degrees latitude, creating high-pressure zones, clear skies, and arid conditions characteristic of deserts.
Why the other options are wrong
- A. The Polar Cell operates at high latitudes (60-90 degrees) and is associated with cold, dry conditions.
- B. Walker Circulation is an east-west atmospheric circulation in the equatorial Pacific, not a global north-south cell.
- D. The Ferrel Cell operates at mid-latitudes (30-60 degrees) and is associated with temperate zones.
Hadley Cell
The Hadley Cell is a tropical atmospheric circulation cell that extends from the equator to approximately 30 degrees latitude in both hemispheres, characterized by rising air near the equator and sinking air at 30 degrees.
- Drives trade winds.
- Responsible for the formation of major deserts at 30° latitude.
- Warm air rises at the equator, cools, and descends at 30°.
Memory trick: Hot air from the equator Had-ley to go up, then down at thirty, making deserts dry.