Final answer:
Warm, water-laden air lifting over a mountain range causes orographic precipitation. The cooling and condensation of water vapor result in rain on the windward side and a rain shadow, a dry area, on the leeward side, leading to significant climate differences around the mountain range.
Step-by-step explanation:
When warm, water-laden air blows against a mountain range, the air is pushed upward leading to orographic precipitation, which is a type of precipitation that occurs when moist air is lifted and cooled as it moves over a mountain barrier. This process often leads to the formation of rain shadow areas on the leeward side of the mountain range.
The uplifted air from the ocean loses heat and its ability to hold water vapor as it rises over the mountain range. Consequently, the vapor condenses and falls as precipitation on the windward side. This results in abundant rainfall in those areas. However, as the air descends on the leeward side, it warms up and any remaining moisture evaporates, leading to arid conditions and creating the rain shadow effect.
This phenomenon significantly impacts the climate and ecosystem on both sides of the mountains, such as the Cascades and Sierra Nevada, which influence the distribution of rainfall and the aridity of regions in their rain shadow such as eastern Washington and eastern Oregon.