Recently, China is experiencing a wave of strong cold wave weather, and there is even a spectacle of West Lake freezing. This is partly related to global warming. While global warming has led to an overall increase in temperatures, it has also led to warming in the Arctic and weakening of the westerly jets, which in turn has triggered polar vortices** and cold air moving south. So even though we are experiencing a cold winter, this does not contradict the trend of global warming.
(1) The relationship between global warming and cold waves
Global warming has led to the warming of the Arctic and the weakening of the westerly jets, which in turn has triggered polar vortices** and cold air moving south. Temperatures in the Arctic are rising faster than in the middle and low latitudes, where the intensity of the westerly jet stream weakens due to the reduced temperature difference. The stable polar vortex is confined to the Arctic region by the westerly jet stream, but in the context of global warming, the polar vortex becomes unstable, and in the cold season, it will occur ** and move southward, bringing the impact of cold waves.
(2) Rollercoaster ups and downs of temperature
Recently, the temperature in our country has shown a rollercoaster of ups and downs. In early December, the temperature in most parts of China was warm, but from December 14, it was affected by a wide range of cold wave weather, and the temperature dropped sharply, and the temperature in some areas even broke through the historical extreme. This phenomenon of warm and cold fluctuations is relatively common in winter, and is not only affected by global warming, but also related to the disturbance of the Arctic vortex** and the westerly wind belt in the middle and high latitudes.
(3) A variety of factors affecting cold wave weather
The intensity of cold wave weather depends not only on the effects of global warming, but also on the activity of the Arctic vortex and the westerly wind belt in the mid- and high-latitudes. In addition, El Niño can also have an impact on cold air activity. The El Niño-induced anomalous anticyclone in the Philippines transports tropical water vapor to mainland China and meets cold air from high latitudes, resulting in the occurrence of snowfall.
According to the National Climate Center, the ups and downs of cold and warm winters are likely to continue to be noticeable, and temperatures may experience a rollercoaster of changes again. The intensity of the East Asian winter monsoon is generally weak, except for the low temperature in the northeast of Inner Mongolia, the northern part of Heilongjiang, most of the country and the southern part of Qinghai, the temperature in most parts of China is close to the normal level.
In terms of precipitation, the precipitation in the central and eastern parts of China is more, and the precipitation in the rest of the country is close to the normal level or less. The cold air activity is more active, and strong cooling and snowfall may occur in the northern region, while low temperatures, rain, snow and freezing weather may occur in the southern part of the Yangtze River and the eastern part of the southwest region. In addition, in the context of global warming, the frequency and intensity of extreme weather events are likely to increase, and more frequent cold spells may occur.
Overall, although we are experiencing cold weather, this does not rule out the trend of global warming. Global warming has led to the warming of the Arctic and the weakening of the westerly jets, which in turn has triggered polar vortices** and cold air moving south. Future weather** shows that temperatures are likely to continue to fluctuate in the winter and the frequency of cold spells is likely to increase. Therefore, while dealing with cold weather, we also need to pay attention to the impact of global warming and strengthen measures to combat climate change.