Why does ground hardening absorb more solar radiation?

Because the reflectivity of the ground depends on the nature and state of the ground, the ground is smooth after hardening, which absorbs more solar radiation and transmits more heat to the atmosphere.

the ground reflectivity depends on the nature and state of the ground. Generally speaking, the reflectivity of dark soil is smaller than that of light soil, wet soil is smaller than that of dry soil, rough surface is smaller than that of smooth surface, the average reflectivity of land surface is 1-35%, and the reflectivity of new snow surface is the largest, reaching 95%.

the water surface reflectivity varies with the solar altitude angle, and the smaller the solar altitude angle, the greater the reflectivity. For the undulating water surface, the average reflectivity is about 7-1%. Therefore, even if the total radiation intensity is the same, the solar radiation obtained by different underlying surfaces is still very different, which is one of the reasons for the uneven distribution of ground temperature.

Influencing factors of solar radiation:

1. Latitude position

The low latitude leads to the high angle of the sun at noon, and the distance of solar radiation passing through the atmosphere is short, which is less weakened by the atmosphere, and more solar radiation reaches the ground; On the contrary, it is less.

2. Weather conditions

In sunny weather, because the clouds are few and thin, the atmosphere has a weak weakening effect on solar radiation, and the solar radiation reaching the ground is strong; In rainy weather, due to the thick and numerous clouds, the atmosphere has a strong weakening effect on solar radiation, and the solar radiation reaching the ground is weak.

3. Altitude

The altitude is high, the air is thin, and the weakening effect of the atmosphere on solar radiation is weak, so the solar radiation reaching the ground is strong; On the contrary, it is weak.

4. The length of sunshine

The sunshine time is long, and the solar radiation is strong; Short sunshine time, weak solar radiation. For example, in summer in China, the temperature difference between the north and the south is not large, because the higher the latitude, the longer the daytime, which makes up for the energy lost due to the low solar altitude.