Labs / Geography
Rain Shadow Effect
Ocean wind carries damp air toward a mountain. As it climbs the windward slope it cools, the moisture condenses into cloud and rain, and the air that finally pours down the far side is warm and bone-dry. Drag the peak up and down, or turn the moisture and wind dials, to see a lush green slope and a desert form on opposite sides of the same ridge.
Windward —Leeward —Cloud base —Lee warming —Biome —
What to try
- Raise the mountain higher and higher. Does the leeward side get warmer or cooler as the peak climbs?
- Where does the cloud first appear when the incoming air is very moist versus quite dry?
- Can you find a mountain low enough that no rain falls at all? What happens to both slopes then?
- Why is the air rushing down the leeward side warmer than the air that arrived over the ocean?
- Turn the wind up. Does faster wind change how much rain the windward slope collects?