What caused the weather to get cold?

The cold weather is caused by La Nina phenomenon.

Affected by La Nina phenomenon, the water temperature in the equatorial western Pacific Ocean is high, and the water evaporation increases, leading to the east

Sub-regional meridional circulation anomaly. In addition, since the spring, the northerly airflow has prevailed in the north of China, while the warm and humid airflow in the southeast is relatively weak. Therefore, cold waves and strong winds frequently appear in the north. At this time, East Asia is being affected.

The impact of the Asian high. Therefore, it has strengthened the power of Siberian cold air moving rapidly southward. After the cold air crossed the border, the temperature plummeted.

Mr. Yang, chief forecaster of China Meteorological Bureau, said: This year, because everyone feels global warming, the characteristics of warm winter are obvious. In winter or early winter, there is less cold air in most parts of the country, one is weak and the other is less frequent. Because the two conditions that must be met when it is going to snow or rain are warm and humid airflow (the air must have considerable humidity, moisture and high temperature), which comes from the south and comes from the tropical region; Another condition is that there must be cold air.

Air coordination, cold air from the polar regions, from cold regions.