Causes of extreme cold weather in the United States

Vladimir Ryabinin, an expert of the World Meteorological Organization, said in an interview with the media that the southward polar vortex is the main cause of extremely cold weather, while the polar warming is the inducement hidden under the surface.

The so-called polar vortex is a large-scale cold air vortex active in polar high altitude, and its influence is usually limited to polar regions and high latitudes. Ryabinin analyzed that the temperature rise in the Arctic caused by climate change is more serious than that in other places, and the temperature difference between the polar region and the mid-latitude region is reduced, which weakens the ability of the polar high to control the polar vortex and causes the polar vortex to "wander" to the mid-latitude region. Reflected in the weather, the possibility and frequency of cold air "invading" mid-latitude areas, causing large-scale temperature drop and snowstorm are increasing.

Of course, it gets hot when it's cold. Just like the freezing weather in the United States thousands of miles away, European countries are warm and harmonious everywhere, and the highest temperature in many western European cities during the day exceeds 10 degrees Celsius. Ryabinin believes that there is a close relationship between them. Influenced by North America controlled by high pressure, the Atlantic depression at the same latitude will transport warm air to Europe.

As mentioned earlier, Ryabinin emphasized that this abnormal weather phenomenon is closely related to the polar climate change in recent years.

The fifth periodic report on climate change assessment released by the United Nations Intergovernmental Panel on Climate Change (IPCC) last year also shows that the probability of extreme weather events such as drought, typhoon and flood is increasing due to climate change.