Affected by clear sky radiation, many friends shouted "cold" yesterday morning. Indeed, from last night to around sunrise this morning, the temperature in Shenzhen dropped all the way, and yesterday morning was colder than the same period the day before yesterday. I believe everyone has such a question: It is still a little hot at noon. Why does the temperature suddenly turn cold in the morning and evening? Why is the temperature difference between day and night comparable to riding a roller coaster? Here, we will discuss clear sky radiation with you.
The so-called clear sky radiation refers to the phenomenon that the ground will cool down when there is no cloud or partial cloudy at night. Because the cloud is like a quilt, it keeps warm at night. If there is no cloud or it is very cloudy at night, it seems that you will feel cold when you sleep without a quilt at night. It's sunny recently, and it's cloudy for some time. Under the influence of weak cold air and clear sky radiation, the temperature difference between day and night has also increased. Unconsciously, February is over. What's your impression of the weather in February?
In February, the main climate feature of our city was "warmer and less rain, and the drought days in the second half of the month broke records". As of February 26th, the monthly average temperature was 18.9℃, which was 2.3℃ higher than the normal period (16.6℃), making it the fifth highest in history. The highest temperature is 28.4℃, the eighth highest in history; The lowest temperature 1 1.4℃ is the third highest in history.
The average rainfall in the whole city (including Shenshan Mountain) is 65438±0.8mm, which is 97% less than the same period in the last five years (66.6mm) and the lowest in the last ten years. In the first half of the month, the warm and humid airflow was active and the weather was warm and humid. It turned sunny and dry in the second half of the month, and the number of dry days (minimum relative humidity ≤ 50%) was 1 1 day, the highest in history.