D. How do mountains in California affect the weather?

Mountains in California significantly influence the weather through a variety of mechanisms, primarily related to orographic lift, rain shadow effects, and temperature variations. Here’s a detailed explanation of how these processes work: 1. **Orographic Lift**: - When moist air from the ocean moves inland, it encounters the Sierra Nevada mountain range. As the air rises over the mountains, it cools and condenses, leading to precipitation. This process is known as orographic lift. - The western slopes of the Sierra Nevada receive substantial rainfall due to this effect, resulting in lush forests and diverse ecosystems. 2. **Rain Shadow Effect**: - After the air has risen and lost moisture on the windward side of the mountains, it descends on the leeward side (the eastern slopes). As the air descends, it warms and dries out, creating a rain shadow. - This results in significantly less precipitation in areas like the eastern Sierra and the Great Basin, leading to arid conditions and desert landscapes. 3. **Temperature Variations**: - Mountains can also create microclimates. Higher elevations tend to be cooler than lower areas, which can lead to different weather patterns within short distances. - For example, while it may be warm and dry in the valleys, temperatures can be much cooler in the mountains, affecting local weather conditions. 4. **Influence on Storm Patterns**: - The presence of mountains can alter the path of storms. Storm systems may be deflected or intensified as they interact with the mountain ranges, leading to localized weather phenomena. 5. **Seasonal Changes**: - In winter, the Sierra Nevada can receive heavy snowfall, which is crucial for California's water supply. The snowpack acts as a reservoir that melts in the spring and summer, providing water for agriculture and urban areas. In summary, the mountains in California play a crucial role in shaping the state's weather patterns through orographic lift, the rain shadow effect, temperature variations, and their influence on storm systems. This complex interaction leads to diverse climates across the state, from the wet coastal regions to the dry deserts.