People who love plateau travel must have this question: if plateaus are closer to the sun, why are they colder? This phenomenon is especially obvious in mountain systems — for example, the snow that never melts at the mountaintop. What causes the higher you go, the colder it gets? Let’s try to explain:
1. Because of low air pressure and thin air. High-altitude areas have poor atmospheric insulation, leading to significant heat loss.
2. There are fewer clouds at high altitudes, so the nighttime counter-radiation effect on the ground is weaker, resulting in lower temperatures. Due to the high altitude, less heat is absorbed from the ground during the day, so as altitude increases, the temperature decreases.
3. The temperature of the atmosphere mainly comes from the Earth’s long-wave radiation. At high altitudes, the air is thin. During the day, less of the ground's long-wave radiation is absorbed, so the temperature is lower; at night, the atmospheric insulation is poorer, also resulting in low temperatures. Therefore, the higher the altitude, the lower the temperature. Within the troposphere, for every 100 meters of altitude increase, the temperature drops by approximately 0.6 degrees.
In simple terms:
The temperature changes we feel do not come directly from the sun’s heat but from the air above the Earth. The Earth absorbs the sun’s heat and releases it into the surrounding air. As a result, the air gradually warms up from the bottom up. Therefore, the higher the mountain, the less heat it receives from the atmosphere, and the naturally colder it is. Also, the higher the mountain, the thinner the air, which retains even less heat. That’s why when we climb high mountains close to the sun, we don’t feel too hot — instead, we feel very cold.