When clouds pass over mountain ranges, precipitation often occurs on the seaward side of the mountain. Which of the following explains why this happens?

Question

A.
The mountains act as a barrier and prevent the clouds from traveling farther inland.
B.
The mountains release heat energy, which warms the water vapor in the air.
C.
The mountains force the clouds to rise, and they cool as they rise.
D.
The mountains create a high pressure system which leads to rainfall.

Answer 1

The correct explanation for why precipitation often occurs on the seaward side of mountain ranges is:

C. The mountains force the clouds to rise, and they cool as they rise.

This process is known as orographic lift. When moist air encounters a mountain range, it is forced to rise over the mountains. As it rises, the air pressure decreases and the air cools, leading to condensation of the water vapor in the air and resulting in precipitation. This is why the windward side (the side facing the incoming moisture) typically receives more rainfall, while the leeward side may experience a rain shadow effect with significantly less precipitation.