How is the cold wave formed?
How is the cold wave formed?
The formation of the cold wave is generally mainly the cold high pressure that broke out in the Arctic, Siberia, Russia and southern Mongolia. The so-called cold wave refers to the cold air from high latitudes, which is rapidly strengthened in a specific weather situation and invades the middle and low latitudes, causing a wide range of severe cooling, strong winds and rainy and snowy weather along the way. Most of these areas are located in the Arctic. In winter, there is no sunshine for a long time, and there is snow and ice everywhere. The air masses staying in these areas are getting colder and drier. When this cold air mass accumulates to a certain extent and the air pressure increases to a level much higher than that in the south, it is like a flood stored in a mountain. At the first opportunity, it floods to the south with lower air pressure, forming a cold wave. According to the regulations of China's meteorological department, if the temperature drop caused by cold air intrusion reaches more than 10 degrees Celsius and the lowest temperature is below 5 degrees Celsius in one day, it is called a cold wave process. But in fact, this standard set by experts does not apply to southern provinces.
What is the phenomenon of cold wave?
Cold wave is a kind of disastrous weather in winter, and people are used to calling it cold wave. The so-called cold wave is a weather process in which cold air from the north invades China on a large scale, resulting in a large-scale sharp cooling and northerly winds. Cold waves generally occur in late autumn, winter and early spring. According to the regulations of China's meteorological department, if the temperature drop caused by cold air intrusion reaches more than 10℃ and the lowest temperature is lower than 5℃ in one day, it is called a cold wave process. Located in the Arctic at high latitudes, Siberia and the Mongolian Plateau, the ground rarely receives the heat of the sun all year round. Especially in winter, when the sun moves south, the angle of the sun in the northern hemisphere becomes smaller and smaller. So the ground absorbs less and less sunlight heat, and the surface temperature becomes very low. In the Arctic Ocean in winter, the temperature is often below -20℃, and the lowest can reach -60℃-70℃. 5438+ 10 The average temperature in June is often below -40℃. Because the temperature in the Arctic and Siberia is very low, the density of the atmosphere will increase greatly, and the air will continue to shrink and sink, increasing the pressure. This will form a strong, deep and broad cold and high-pressure air mass. When this cold and high-pressure force increases to a certain extent, it will flood into China like a tide that has burst its banks. This is the cold wave.
Official: There may be an extreme cold wave in February next year.
Recently, the cold wave has brought "cliff-like" strong cooling and a wide range of rain and snow weather. Some people question whether the violent cold wave is hitting the face of global warming. In this regard, Zhou Bing, chief expert of climate service of the National Climate Center, said that it is in the context of global warming that the frequency and intensity of extreme weather events such as high temperature heat waves, droughts, floods, typhoons and cold waves have increased. Global warming leads to more unstable climate, and the intensity of extreme cold events is increasing. Global warming has changed the characteristics of global atmospheric circulation, and affected local climate through the interaction between air and sea. In addition, arctic warming is also an important reason for extremely cold weather. It is predicted that 1- the cold air activity will be obviously strengthened in February next year, and the temperature in most parts of the central and eastern regions may be lower than normal, so there is a greater possibility of staged extreme cold wave events. All localities should continue to guard against the adverse effects of low-temperature weather, do a good job in dispatching and supplying energy such as coal, electricity, oil and gas, do a good job in ensuring Spring Festival travel rush, and strengthen fire prevention in forests, grasslands and urban-rural fringe areas.
Is the cold wave affected by monsoon?
Most of China is located in the north temperate zone, bordering the world's largest ocean in the east and the world's largest continent in the west. The thermal properties of land and sea are very different. There is a big difference in air pressure between two seasons in Xia Dong, resulting in a remarkable monsoon climate. The winter winds that affect China mainly come from Siberia and Mongolia. The wind direction in winter is northwest wind, and the cold wave is affected by winter wind, which brings severe weather such as strong wind and cooling. Winter winds are characterized by cold and dryness. Summer monsoon is characterized by high temperature and rainy weather, which is beneficial to agricultural production. Cold wave refers to the cold air coming from polar regions or cold zones in winter half a year, which invades the middle and low latitudes on a large scale like tides. When a cold wave strikes, the temperature will drop sharply, accompanied by strong winds, rain and snow.