Online maps of the cold tide and typhoon routes invading China

Cold wave is one of the disastrous weather systems, which refers to the severe cooling along the way caused by the large-scale invasion of cold air in polar or cold regions under specific weather conditions.

The frost front passes through the region, and the temperature drops sharply in a short time, accompanied by strong winds, often accompanied by rain and snow. After the frost passes through, if the weather is clear and the wind is weak, there are often frosts and frosts. From late autumn to early spring, most parts of China suffer from cold air attacks. In China's Cold Wave Yearbook published in 1980, the criteria for the division of cold waves are as follows: during the period affected by cold waves, the total daily mean temperature process cooling > 10℃ and the absolute value of negative temperature anomaly > 5℃, or the absolute value of total process cooling > 7℃ and the absolute value of negative temperature anomaly > 3℃. If the above criteria are not met, they are called respectively according to the degree of cooling. Strong cold air activity and cold air activity. The cold wave affecting most areas is defined as national cold wave, while the cold wave affecting only some areas is defined as regional cold wave.

There are four main paths affecting China's cold wave: the West cold wave originated from Iceland, Britain and moved eastward along the 45 degrees north latitude line, first arrived in Northwest Xinjiang, China, and then directly arrived in North China, bringing obvious precipitation and more snow in North China; the northwest cold wave originated from Norway and its Arctic Ocean west of New Territories, and then moved eanously. The southeast movement through Russia's Siberia and Mongolia enters China, with frequent occurrences and strong influence, often bringing sand and dust weather; the northern cold wave originates from the Arctic Ocean east of New Territories, and the southern movement through Russia's Siberia and Mongolia enters China, generally bringing gale weather; the northeast cold wave originates from Russia. The Far East and the Okhotsk Sea have a great influence on the northeast of China.