Why is it hot in cloudy days and cold at night?

The reason why the temperature difference between day and night is small is that the temperature is not high during the day and not low at night, so the temperature difference is small.

Clouds are thick during cloudy days, and solar radiation is not easy to reach the ground directly, which reduces the ground radiation, so the temperature will not be very high. So the temperature is lower on cloudy days.

On cloudy days, the clouds are thick at night, and the ground radiation still takes away the heat from the ground. However, because clouds can absorb a lot of ground radiation and convert it into atmospheric inverse radiation, the temperature will be higher at this time.

To sum up, the temperature is not high during the day and not low at night, so the temperature difference is small.

The temperature difference between day and night of extended data is determined by the difference between the highest temperature during the day and the lowest temperature at night. In actual measurement, the highest temperature during the day is often around 14 in the afternoon, and the lowest temperature at night is often before sunrise.

In a period of time, the highest temperature and the lowest temperature are the temperature difference during this period. For example, the highest temperature 18℃ and the lowest temperature -2℃ in a city have a temperature difference of 20℃. Generally speaking, the temperature difference between day and night is larger in inland areas and smaller in coastal areas, because the specific heat capacity of water is greater than that of soil.

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