What caused this cold rain?

This is a superstitious saying: It is no accident that it snows in China. It's because God punishes people who do too much evil, and God is angry! Don't think that we can change the climate on another day. We must never ignore the infinite power of God! Scientifically speaking, the abnormal atmospheric circulation under La Nina phenomenon is the "culprit", and the rare snowstorm has been going on since the founding of New China. In the context of global warming, why is there such a large range of snowfall and low temperature weather in China? According to the latest data provided by the Forecast and Disaster Reduction Department of China Meteorological Bureau, the precipitation in nine provinces, such as Hubei, exceeds 20 years, including Sichuan, Shaanxi, Gansu and Qinghai. Judging from the duration of snowfall, from June 65438+1October 10 to August 28, the snowfall days in Jiangxi, Hunan and other provinces 1 1 provinces are all more than once in 20 years, of which Henan, Shaanxi, Gansu, Qinghai and Shanxi are more than once in a hundred years, and Anhui. According to Yang Guiming, chief forecaster of the Central Meteorological Observatory, compared with many years, the biggest feature of this year's blizzard is the short time interval between rain and snow. He said: "It is not uncommon for rain and snow to occur frequently in three or nine days, but in this year 15 days, there have been three processes, almost once a week, and each time it is a long-lasting large-scale snowfall, which is rare in history." The abnormal atmospheric circulation under La Nina phenomenon is the "culprit" of snowstorm. "The direct cause of the recent large-scale rain and snow weather is the abnormal atmospheric circulation." Sun Jun, chief forecaster of the Central Meteorological Observatory, said. He analyzed that from the evolution of atmospheric circulation in the short and medium term, there have been frequent cold air and active warm and humid airflow since the winter of this year. Especially since June+10 in 5438, the circulation in the middle and high latitudes is mainly meridional, with frequent cold air activities. In addition, the subtropical system is strong, northwest than normal, which is conducive to transporting warm and humid air from the south to the north. On the one hand, the cold air in the north is very active, and the warm and humid airflow in the south is constantly transported northward. The intersection of cold and warm air currents is mainly located in the central and eastern regions of China, which creates favorable circulation conditions for large-scale rain and snow weather. This year's atmospheric circulation anomaly is related to the "La Nina event" that is taking place in the equatorial Middle East Pacific. Li Weijing, deputy director of the National Climate Center, said that from the perspective of climate change, the current low temperature in the equatorial Middle East Pacific is one of the manifestations of the "La Nina" phenomenon. Statistical analysis shows that the meridional dimension of mid-latitude atmospheric circulation may be strengthened in the winter of the year and the spring of the following year when the strong La Nina event occurred, that is, frequent cold air activities may easily lead to low temperature in most parts of northern and eastern China and more precipitation in the north of the Yangtze River. Why is this year's heavy snow so slow to "recede"? Experts attribute the reason to the stability of atmospheric circulation. Sun Jun said: "It is precisely because of the stable atmospheric circulation during this period that the warm and humid airflow and cold air in the southwest have been around 30 degrees north latitude, especially in the middle and lower reaches of the Yangtze River, so there will be no obvious turning point in the recent rain and snow weather." Yang Guiming introduced that there are several kinds of cold air affecting China: First, the cold air mass comes from polar directions, such as Mongolia and Lake Baikal, and the cold air force is strong, mainly due to strong winds and cooling processes. Second, the cold air mass from Siberia will also bring strong winds and cool weather, but the intensity is not as good as the former. There is also a kind of cold air coming from the west road, such as starting from Iceland, passing through the European Mediterranean and coming from west to east. This kind of cold air is easy to bring a wide range of snowfall. "The continuous snowfall in China this year is because the southwest warm and humid airflow from the west road meets the cold air east of Lake Baikal on the east road in Huanghuai, Jianghuai and northern Jiangnan. In addition, the warm and humid airflow in Huanghuai is more active, and it is prone to snowstorm weather. "