What is the cold wave when the temperature drops suddenly?

Cold wave is a kind of disastrous weather. It is a large-scale strong cold air activity. The standard of cold wave is: within 48 hours, the minimum temperature in the Yangtze River basin and its northern area drops to above 10℃, and the minimum temperature in the middle and lower reaches of the Yangtze River reaches below 4℃, accompanied by strong winds of 5-7 on land and 6-8 at sea.

Cold wave cold air affecting China is mainly formed in polar regions, Siberia and Mongolia. Generally speaking, cold air affects China in three ways: West Road, Middle Road and East Road. Not every cold wave can reach the south of China, and some only reach the Yangtze River basin or turn east in the north of the Yangtze River. Which way the cold air takes does not depend entirely on the cold air path before entering China, but mainly depends on the strength of the ground cold high pressure and the circulation situation. The cooling caused by cold wave is most obvious in northwest and northeast China.

Why is the cold wave a disastrous weather? Mainly because when the cold wave strikes, the temperature drops suddenly, accompanied by strong winds, sandstorms, precipitation and frost. These weather processes have brought serious harm to the winter wheat areas in northern China. Spring also brings sandstorm weather to the dry and loose areas in northwest China and Inner Mongolia. It can also cause large-scale rain and snow weather in the south of the Yangtze River, accompanied by lightning, hail and other phenomena. However, the Qinghai-Tibet Plateau and Yunnan-Guizhou areas in China are less affected by the cold wave.

In daily life, people often refer to the cold wave as the cold wave, but in fact this familiar name is wrong.

From our previous discussion on the cold wave, you can easily find that the cold wave is a meteorological term and a weather process, which breaks out in late autumn and has timeliness and seasonality in early spring.

Cold wave is a special term of oceanography, which means that large-scale seawater flows in a certain direction at a relatively stable speed, and the water temperature is lower than the ocean current in the passing sea area.

From the semantic point of view, the word "flow" has a non-stop meaning, while the word "tide" has the nature of explosion and cycle, and it is rapid and turbulent with a short duration.