What is a Rainshadow?

 

Definition of a Rainshadow: As air moves up over a mountain range, it gets cold and loses the ability to hold moisture - so it rains or snows on the mountain. When the air moves down the other side of the mountain, it gets warmer. Warm air can hold lots of moisture, so it doesn't "let go" of the water vapor in the form of precipitation (rain, fog, snow) much at all. The other side of the mountain which receives no rain is said to be in the "shadow" of the mountains because of this atmospheric effect. The Amazon River The Atacama Desert