The national ＂avoid baking＂ map is released, and the high temperature hits you. …

　　China Meteorological News reporter Cui Guohui

　　From June 24 to 25, Beijing issued high-temperature warning continuously, Tianjin upgraded the yellow warning signal of high temperature to orange, and some cities in northern Shandong, eastern Hebei and southern Hebei also ushered in a big "roast". The citizens have said that how to say that it is hot on this day is simply a "teppanyaki" without a word!

　　Anyway, how "baked" is this summer? Why is it hotter in the north than in the south recently? How can the public avoid "baking"? This issue of "Chat" will talk to you.

　　what is actually happening

　　The high temperature of 35℃ to 37℃ in Huanghuai, North China locally exceeded 38℃

　　In China, it is generally called high temperature when the daily maximum temperature reaches or exceeds 35℃, and the high temperature weather process for several days (more than 3 days) is called high temperature heat wave (or called high temperature heat wave).

　　According to the monitoring data of the Central Meteorological Observatory, the high temperature areas in China were mainly concentrated in Beijing, Tianjin, eastern and southern Hebei, northern Shandong, northern Henan, eastern Inner Mongolia, western Jilin, western Liaoning and other places on June 24, and the scope was not too large. The highest temperature in the above areas is generally between 35℃ and 37℃. Among them, high temperature weather of 38℃ to 39℃ appeared in central and southern Tianjin and central Hebei. The highest temperature is 38.9℃, which appears at Tianjin Urban Climate Monitoring Station.

　　Due to the rapid rise in temperature, people obviously feel the heat in summer. But compared with the same period in history, there is still a big gap. In the same period of history, the highest temperature extremes in the above areas all exceeded 40℃, basically ranging from 41℃ to 42℃.

Chart Planning: Cui Guohui Production: Ding Qian

　　cause

　　Under the control of anticyclonic circulation, the weather is fine and the radiation warming is obvious

　　Ma Xuekuan, chief forecaster of the Central Meteorological Observatory, said that the main reason for the high temperature process in North China and Huanghuai areas was radiation warming.

　　Over the past few days, North China has been controlled by anticyclonic circulation, mainly sunny weather, and the short-wave radiation of the sun has obviously warmed up. In addition, there are warm ridges in the upper air in North China and Huanghuai areas, accompanied by a certain degree of downward flow.

　　Moreover, after a whole winter, the surface condition of the underlying surface in the north is not as humid as that in the south, and the dry environment on the surface is conducive to the temperature rise in a short time.

　　It stands to reason that the earth’s heat comes from the sun, and the closer it is to the sun, the higher the temperature should be. But why is there more high temperature in the north than in the south recently?

　　Ma Xuekuan said that in fact, the high temperature in North China and Huanghuai sometimes began in May. There is more precipitation in the south this season, and the subtropical high has not yet moved north, and the intersection of cold and warm air is mainly in the south. After the onset of the monsoon, the water vapor on the edge of the subtropical high came up, which just affected the southern region. There are many rainfall processes and clouds in the southern region, so it is not easy to have high temperature weather. In the north, however, sunny weather predominates, with less precipitation and weaker cold air. During the intermission of cold air activities, there will be more sunny and hot weather.

　　trend

　　The high temperature continued until around the 28th, concentrated in the south-central part of North China to the northern part of Huanghuai.

　　The Central Meteorological Observatory predicts that this high-temperature weather process will last until around the 28th, mainly concentrated in the central and southern parts of North China to the northern part of Huanghuai, that is, western Shandong, northern Henan, central and southern Hebei and Beijing-Tianjin areas. The high-temperature areas are not fixed every day, and the intensity is mostly at 35℃ to 38℃.

Chart Planning: Cui Guohui Production: Ding Qian

　　Due to the frequent occurrence of high temperature and heat wave weather in recent years, the disasters caused by high temperature are becoming more and more serious. China’s meteorological department has formulated high temperature warning signals, which are divided into three levels: yellow, orange and red. High temperature yellow warning signal generally means that the maximum daily temperature will be above 35℃ for three consecutive days; High temperature orange warning signal generally means that the maximum temperature will rise above 37℃ within 24 hours; High temperature red warning signal generally means that the maximum temperature will rise above 40℃ within 24 hours.

　　High temperature has a certain impact on people’s daily life and health and all sectors of the national economy. High temperature and heat wave make people feel uncomfortable, work efficiency is low, and the incidence of heatstroke, intestinal diseases and cardiovascular and cerebrovascular diseases increases; The demand for water and electricity for heatstroke prevention and cooling has soared, resulting in tight water and electricity supply and frequent failures. High temperature intensifies soil water evaporation and crop transpiration. When high temperature and little rain occur at the same time, it causes serious soil moisture loss, accelerates the development of drought and has a great impact on agricultural production. In addition, tourism, transportation, construction and other industries will also be affected to varying degrees.

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(Editor: Su Yujun)