Final answer:
The altitude of the sun influences the concentration and intensity of solar radiation that reaches the Earth's surface, with higher sun positions leading to more direct and intense insolation. This affects seasonal temperature variations and can impact global climate and weather patterns.
Step-by-step explanation:
The altitude of the sun affects the amount of solar insulation (insolation) received at any point on Earth because the angle at which sunlight hits the Earth changes with the sun's position in the sky. When the Sun is low on the horizon, sunlight spreads over a larger area and is less concentrated, resulting in less heat per unit area. Conversely, when the Sun is high in the sky, such as during summer at midday, sunlight is more direct and concentrated, leading to greater heating.
Additionally, sunlight must pass through more of the Earth's atmosphere when the Sun is low in the sky, which scatters and absorbs some of the light, further diminishing the intensity of the solar radiation reaching the surface. In contrast, when the Sun is overhead, sunlight travels through less atmosphere, conserving more of its energy to heat the surface.
This concept is crucial in understanding seasonal temperature variations, where the differing sun altitudes during summer and winter lead to differences in heating and consequently the seasons. Additionally, differences in sun altitude affect global climate patterns, atmospheric chemistry, and regional weather systems.