Winter in the south depends on shaking the next sentence

The winter in the south is already shivering with cold by shaking a word.

catch cold

(1) Cold, Chinese vocabulary, Chinese pinyin is hán lěng, which means that people feel cold when the temperature is low. Cold can be divided into wet cold and dry cold. At the same temperature, wet cooling is colder than dry cooling. Cold refers to the feeling of fear of cold and cold climate; Low temperature, feeling cold; Generally used to describe winter.

(2) The cold weather in China is the result of frequent southward movement of Siberian cold air. Siberia is the "cold pole" in the northern hemisphere, which makes China the coldest place at the same latitude in the world. Siberian cold air appears as a cold air mass heading south on the weather map. But the cold air mass is not isolated, it is often a part of a larger weather system-cyclones on the weather map.

(3) The cyclone is mainly composed of a pair of cold and warm air masses, with a cold air mass in the west and a warm air mass in the east. This extratropical cyclone rotates counterclockwise and moves from west to east at the same time. The dividing line between cold and warm air masses is called cold front. After the cold front, the local area changed from warm air mass to cold air mass, and the wind direction changed from south wind to north wind.

(4) This is the truth of the proverb "The south wind blows to the end, and the north wind reciprocates". So there will be a sharp cooling after the cold front. The climate of China is characterized by hot in the south and cold in the north, with a large temperature difference between the north and the south. The winter climate in northern China is cold for two reasons. First, the direct point of the sun in winter is located in the southern hemisphere. The farther north, the shorter the day, and the lower the height of the sun at noon, the less solar radiation energy is obtained.