The main culprit of cold air going south this year may be polar vortex. How does polar vortex affect the weather in China?

True! ! Polar vortex is often the "real murderer behind the scenes" in extremely cold weather. The polar vortex is a big vortex, just like the vortex in water. The center of the cyclone is a low-pressure airflow, which flows into the center from all directions and diverges from the center to all directions. This is the direction of high-pressure airflow. Usually, it is a large cold vortex at high altitude in polar regions. Its position, intensity and movement have a very obvious impact on the weather in polar regions and high latitudes, especially the cold wave weather, which has a vital impact. In 2008, the cause of the large-scale low-temperature rain, snow and freezing disaster in southern China was related to this polar vortex anomaly. In some areas, the latitude is high, the solar radiation is less, the heat is less, the airflow sinks, and a lot of cold air is accumulated. When the vortex leaves the polar region and goes south, it will bring extreme cold to people in mid-latitude areas. However, polar vortex is generally stable, and there are three main forms of existence, each of which has different functions. ? Generally speaking, the first type is ring pole type, with only one vortex center, and generally there will be no cold wave weather; The second type is dipole splitting, which has two closed centers, one in North America and the other in North Asia. When its vortex center is in northern Asia, cold wave weather often occurs. The third is multi-level distribution, which will be divided into three or more centers. If there is polar vortex in Lake Baikal, cold wave weather will often occur in China.