The high temperature in the north "roasts" the rainstorm in the South "dominates"—— What is the reason for the June of "waterlogging in the South and drought in the north" After several days of high temperature, the rain gently shook down the temperature in Beijing on June 22. However, this slight coolness was only a short stay. As soon as the sun shone on the 23rd, the temperature in Beijing immediately jumped to 36 ℃. However, compared with the 40 ℃ temperature in Henan, Hebei, Shandong and other places, and the 70 ℃ surface temperature, it is nothing. In Xuchang, Henan Province, the high temperature in recent days has caused the local cement road to "heat up". The North these days is like "Teppanyaki". But in the south, it is a different scene. Affected by the continuous large-scale heavy rainfall, floods occurred in many places in South China and Jiangnan, and 117 rivers in the Pearl River Basin exceeded the alarm. On June 15, Guangzhou's central urban area experienced a high tide with a return period of more than 100 years, and all passenger ship routes in the urban area were suspended. Netizens said that Guangzhou has become "Guangzhou". For the mode of "high temperature in the North + rainstorm in the South", netizens lamented that the sunny and rainy days in the north and South were not interconnected, and they felt a completely different summer. "Waterlogging in the South and drought in the north" is this June normal? Why? The reporter interviewed Yuanyuan, researcher of the climate prediction Office of the National Climate Center, Zhang Tao, chief forecaster of the Central Meteorological Observatory, Hu Xiao, chief meteorological analyst of China Weather Network, Zhoubing, chief expert of meteorological services of the China Meteorological Administration, and xuxiaofeng, President of the China Meteorological Services Association. Reporter: is it normal for Northern China to "roast" in June? Is it early? Yuan Yuan: compared with previous years, this year's regional high temperature did not happen earlier. On the contrary, the cold air was more active from May to the first half of June, and the northern region has been very cool. However, after June 15, a regional high temperature event occurred in North China and the Huang Huai Region. Zhang Tao: the high temperature weather is not abnormal in this season, but it is an abnormal situation for those areas where high temperature occurs. For example, in many areas of North China and the Huang Huai River, including many areas in Shanxi, the maximum temperature has broken through the historical extreme value of the same period. Whether such high-temperature weather will occur in the future is still unclear, but it will certainly occur again on a large scale in the country. The high-temperature weather on a large scale has not really started in terms of climate normality. For example, the most typical high-temperature and drought weather in Jiangnan usually comes in July. The high temperature in most parts of the north, such as the northeast and northern North China, has not really started. Reporter: what is the cause of this round of hot weather? Yuan Yuan: since June, the water vapor conditions in the lower troposphere of the Huang Huai Region have deviated. Most areas have mainly sunny, hot and rainy weather, with less precipitation. Especially after June 15, the air over Huang Huai Region was controlled by high pressure ridge, and the downdraft caused obvious warming effect; At the same time, affected by the solar short wave radiation in the daytime, coupled with the dry atmosphere, the ground temperature rises rapidly. The combination of these factors leads to high temperature weather. In the future, the high temperature in the north will gradually weaken. After the Northwest Pacific subtropical high rises northward, the subtropical high will mainly control the areas of Jiangnan and the Middle East of South China. The high temperature in the South will begin to develop and strengthen, and high temperature weather may occur for a long time. Hu Xiao: this high temperature weather is mainly affected by the eastward shift of the high pressure ridge, resulting in sunny, hot and rainy weather in many parts of the north. In addition, due to the influence of solar short wave radiation during the day, the weather is dry, which is conducive to the gradual rise of the ground temperature. The significant high surface temperature is mainly caused by strong solar radiation. Reporter: will there be more extreme high temperatures this year? Yuanyuan: it is expected that in the midsummer (July August), the south of China, mainly the Middle East of Jiangnan and the Middle East of South China, may have a long-term high-temperature weather process. Against the background of global warming, extreme weather and climate events have occurred frequently in recent years. It is necessary to pay special attention to the occurrence of extreme high temperatures and the possible adverse effects on people's production and life and energy supply, and take timely preventive measures such as power supply. Reporter: why is there so much heavy rainfall in the south this summer? Zhou Bing: this year, the heavy rainfall in South China lasted for a long time and accumulated a lot. It has been stable in South China and Jiangnan for more than a month. In some areas, it rained 28 days out of 30 days. Since May, 10 precipitation processes have occurred in South China, Jiangnan and other places. According to the statistics of the National Climate Center, from May 1 to June 15, the regional average rainfall in Fujian, Guangdong and Guangxi provinces was the highest since 1961. On the one hand, under the background of global warming, the instability of the atmospheric general circulation system has strengthened, resulting in enhanced convective activities, higher precipitation efficiency and higher rainfall; On the other hand, the ongoing La Nina event has provided an important climate background for the early onset of summer storms in the South China Sea and the early progress of China's rainy season this year. The southwest water vapor transport led by the monsoon circulation is relatively strong, and the subtropical high is relatively stable, which is conducive to the continuous transport of water vapor from the Northwest Pacific and affects South China and Jiangnan of China. In addition, with abundant water vapor conditions, the meridional degree of the atmospheric circulation in the middle and high latitudes of Europe and Asia increases, and the cold air activities affecting the eastern part of China are frequent. Especially since June, the cold vortex in the Northeast has become more active and developed southward, leading the cold air southward to affect the southern part of the Yangtze River Delta to southern China, resulting in abnormal precipitation in the pre flood season in southern China. Reporter: when will this round of continuous rainfall end? Zhou Bing: it is expected that in the next 10 years, the rain belt will rise northward in a ladder shape, and the continuous heavy rainfall in South China will end. The rain belt will jump north to the vicinity of the Huang Huai River and the Jiang Huai River. The heavy rainfall weather that has lasted for more than a month in South China and Jiangnan will eventually weaken and usher in less rain and high temperature weather. In the coming flood season in July, the rain belt will be mainly in the north, north of the Huaihe River, North China and south of the northeast. In the future, with the active typhoon, the southern region may encounter heavy rainfall again. It is necessary to pay attention to prevent mountain torrents, landslides, debris flows, urban and rural waterlogging and other disasters that may be caused by heavy rainfall. Xuxiaofeng: Although the heavy rainfall in South China is coming to an end, the rainy season is still in its initial stage nationwide, and more vigilance is needed in Jiangnan, Jianghuai, North China, northeast, southwest, northwest and other places. From the conventional situation, extreme drought and flood are easy to occur, with more rainfall in the early stage, and attention should be paid to drought prevention in the later stage. According to the weather and climate conditions that have occurred so far, the temporal and spatial anomalies are obvious, and the probability of extreme weather in the later period increases. Reporter: the monitoring results of the National Climate Center show that the La Nina event that began in the autumn of 2021 is still continuing. Is the recent extreme weather related to La Nina? Yuan Yuan: the La Nina event is not the direct cause of the current round of global high temperature, but it is one of the main factors affecting China's summer climate anomalies. Judging from the climate anomalies that have occurred so far, the summer storms in the South China Sea this year started earlier than usual, the pre flood season in South China and the rainy season in Southwest China started earlier, and the plum blossom in the South China and the middle and lower reaches of the Yangtze River also started earlier. The continuation of La Nina event has provided an important climate background for these early seasonal processes. The La Nina event that began in the autumn of 2021 is still continuing. At present, the attenuation is slow and slightly strengthened in May. The National Climate Center predicts that the La Nina event will weaken slightly in summer, and the sea surface temperature in the equatorial Middle East Pacific may maintain a weak cold water state in summer, but the sea surface temperature will develop and strengthen again in autumn and winter this year. Under the background of global warming, the atmosphere becomes more unstable and extreme events are frequent. (reporter cuixingyi) (outlook new era)