Rain Shadows(The Orographic Effect)

Rain Shadows:

Area of land that receives less

precipitation because of a Mountain Range to its

windward side.

Air MassesCalifornia wind usually

blows West (Pacific Ocean) to the East. As it travels over the

Pacific Ocean, it picks up moisture.

Air mass hits Coast Range Mts. & has to rise approx. 3,500 to pass over to the other side.

As the air rises, it cools at a rate of 30F/ 1000 feet.

Cool air holds less moisture than warm air.

Air cools then the water condenses.

A rain cloud forms.

Once over the top of the mountain,

the air falls, warms, and the rain stops.

Western side = Rainfall. The Biome is a Forest

Eastern side = Not much rain.The Biome is a Desert.

EastWest