Final answer:
The rainshadow effect refers to the climate pattern where the leeward side of a mountain range is significantly drier than the windward side, caused by moist air losing its moisture as it passes over the mountains. This leads to semi-arid or arid conditions as seen in regions influenced by the Himalayas, the Andes, and the Great Plains in the United States. The correct option is d.
Step-by-step explanation:
The effect produced when mountain barriers trap moisture on the windward side, leaving the leeward side much drier, is known as the rainshadow effect. This occurs when moist air from the ocean rises over a mountain range, cools, and precipitates its moisture on the windward side.
Subsequently, as the air descends on the leeward side, it warms up, becoming drier, which causes a reduction in precipitation and results in semi-arid or arid conditions.
The Himalayas and the Andes mountain chain are notable examples where this effect significantly influences the regional climate, causing high levels of aridity in areas such as western China and the Atacama region of Chile.
Similarly, the rain shadow effect creates differing conditions on Hawaiian islands such as Kauai, where one side may receive significant rainfall, while the opposite side experiences semi-desert conditions. In the United States, the Great Plains encounter a semi-arid climate due to the rain shadow effect of the western mountain ranges.
Hence, Option d is correct.