Why are there so many extreme weather this year?

It is the alternation of greenhouse effect and La Nina phenomenon!

Probably this winter is the reason for the extreme freezing weather in the south-

1. Mr. Yang, chief forecaster of China Meteorological Bureau, said: In winter or early winter, there is less cold air in most parts of China, one is weak and the other is not frequent. Because we all know that the two conditions that must be met when it snows or rains are warm and humid airflow (the air must have considerable humidity, moisture and high temperature), which comes from the south and from the tropical region; Another condition is that there must be cold air, which comes from the polar regions and from the mountainous areas. The cold air affecting our country in the early winter of this year is relatively weak, and the frequency is not much. Even with warm and humid airflow, it is not easy to snow without cold air. Therefore, before 1 month, there was relatively little precipitation, dry air and high temperature in most parts of China. However, in 1 month, great changes have taken place in the atmospheric circulation, making the cold air activities in China more active. After the cold air is active, the warm and humid air flow at low latitudes gradually strengthens, just combining cold and warm. Therefore, during this period, the cold air is relatively strong, the cold air activity is relatively frequent, and the warm and humid airflow is relatively strong. These two air currents have the same influence and meet by coincidence. So recently, especially in the Yangtze River basin, there are more rainy and snowy weather, and the low temperature weather lasts for a long time.

2. Personally, I think it may be caused by the cold front weather caused by the cold air mass formed by the southward Asian high originating from Mongolia and Siberia. But simply from the perspective of the Asian high and cold front heading south, isn't it a bit one-sided? In that case, there will be low temperature snowfall in eastern China every winter. But how to explain the reason for such a rare large-scale continuous snowfall this year?

I think the most important reason for this abnormal weather is La Nina. Affected by La Ni? a phenomenon, the water temperature in the equatorial western Pacific Ocean is high, and the water evaporation increases, which leads to the abnormal meridional circulation in East Asia. In addition, since the beginning of spring, northerly airflow has prevailed in northern China, resulting in frequent cold waves and strong winds in the north. We know that at this time, East Asia is being affected by 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. In addition, the warm and humid air flow from the southwest Indian Ocean to the north continuously increases the humidity and interacts with the cold air, thus forming continuous topographic precipitation (snow). Caused the recent continuous low temperature snowfall.

The above is just my personal opinion, I hope I can help you:)

3. In addition, netizens said:

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The explanation is very clear!

I hope it helps you ~