The relationship between light and heat

Light and heat are important factors of climate. People often think that light and heat are the same, where there is more sunshine, it is hot, and where there is less sunshine, it is cold. This understanding is one-sided. Light and heat are both related and different. So what is the relationship between light and heat?

Illumination, focusing on the amount of solar radiation, is generally related to weather conditions, sunshine hours, topography and other factors. There are two main factors that affect the duration and intensity of sunshine:

1 and sunshine hours are related to the length of day and night.

Take the summer half year in the northern hemisphere as an example. The higher the latitude in the northern hemisphere, the longer the day and the more sunshine hours.

2. The sunshine intensity is related to the weakening of the atmosphere.

The less precipitation, the less attenuation and the stronger illumination; The higher the altitude, the thinner the air, the less attenuation and the stronger the light. The lower the latitude, the greater the altitude angle of the sun, the shorter the distance through the atmosphere, the less attenuation and the stronger the light; To sum up, light is mainly related to precipitation, altitude, latitude and the length of day and night.

The calculation method of heat is to subtract the energy lost at night from the solar radiation energy obtained during the day. We use the accumulated temperature to measure the amount of heat. There are two main factors that affect the accumulated temperature:

1, daytime temperature is related to atmospheric weakening.

During the day, the less attenuation, the more light the ground gets, especially in low latitudes. The greater the solar altitude angle, the smaller the irradiation area, the stronger the light energy per unit area and the higher the ground temperature. The more ground radiation is transmitted into the atmosphere, the higher the temperature. This is similar to the second point that affects illumination, and the main influencing factor is latitude.

2. The temperature at night is related to the insulation of the atmosphere.

At night, the ground loses heat. The more clouds there are, the more ground radiation the atmosphere absorbs, the more radiation it gives back to the ground, and the richer the heat.

The relationship between light and heat is complementary and mutually restrictive, and they change through different conditions.