China News Service, Beijing, September 2 (Wei Xianghui) At present, the continuous high temperature weather in the south has ended.

This summer, while the south was experiencing scorching heat, parts of the north were flooded.

What is the reason for this year's "drought in the south and flood in the north"?

Will this phenomenon become a new trend?

The picture shows the waters of the Nanchang section of the Ganjiang River, with a large riverbed exposed.

Photo by Liu Zhankun

The high temperature warning in the southern region has been lifted, and the northern region has entered autumn one after another.

  According to statistics from the China Meteorological Administration, from July 21 to August 30, the Central Meteorological Observatory issued high temperature warnings for 41 consecutive days, including 12 consecutive days of high temperature red warnings.

  On August 31, the Central Meteorological Observatory announced that at present, the continuous high temperature weather in the south has ended.

On the afternoon of August 30, the Central Meteorological Observatory lifted the high temperature warning.

It is expected that in the next 10 days, there will be no large-scale high-temperature weather in my country, except that there will be 35-38 ℃ high temperature weather in some basins in Xinjiang, central and southern Hunan, central and southern Jiangxi, and northern Guangxi after September 6.

  With the end of the high temperature season in the south, the cold air in the north began to become active, and various places entered autumn one after another.

  According to China Weather Network, as of August 30, the northeastern region, most of the northwestern region, and the western and northern regions of North China have entered autumn, and the autumn frontier has reached the line from northern Hebei, Shanxi, southern Shaanxi to southern Gansu.

Among the big cities, Harbin, Changchun, Shenyang, Hohhot, Yinchuan, Urumqi, Lanzhou, Taiyuan and other places have already entered the autumn.

On August 30, a gorgeous sunset was seen in Beijing after the rain.

Photo by China News Agency reporter Sheng Jiapeng

Is there an abnormality in the "water and fire double heaven" in the north and south?

  This year, the heavy rain that southerners crave seems to be heading north.

  On August 30, according to the website of the Ministry of Water Resources, since July this year, the Yangtze River Basin has continued to experience high temperature and little rainfall, with less water coming from the river, and the water level has continued to decline. The drought has developed rapidly.

As of August 30, the area of ​​arable land in the Yangtze River Basin was 43.25 million mu, and 4.73 million people and 710,000 large livestock were affected by the drought.

  Previously, in the same period of time when the south experienced a scorching heat wave, parts of the Northwest, North China, and Northeast China ushered in a strong precipitation process, forming an abnormal phenomenon of "southern drought and north flood".

On August 3, the China Meteorological Administration announced at a regular press conference that in July, there were many torrential rains in the northern region and the extremes were strong, and the daily precipitation of 30 national meteorological stations exceeded the extreme value in July.

  According to media reports, since July 11, floods have occurred in Shanxi, Shaanxi, Gansu and other places due to heavy rain.

At 22:00 on August 17, a sudden heavy rainfall caused flash floods and mudslides in Datong County, Xining City, Qinghai Province.

On August 18, there was a sudden torrential rain in Ordos City, Inner Mongolia, and many dangerous situations such as road water accumulation, flooded houses and trapped people occurred in many places.

  On August 17, the General Office of National Defense and the Department of Emergency Management deployed to deal with droughts in the south and floods in the north, requiring strict prevention of heavy rains and floods in the north, and drought and disaster mitigation in the south.

"Large grain-producing county" Dong'an, Hunan does a good job of "water article" to fight drought and protect people's livelihood Photo by Fu Yong

Expert: The overall precipitation is still the pattern of "less in the north and more in the south"

  In fact, "droughts in the south and floods in the north" are nothing new in China.

In March this year, at the press conference of the China Meteorological Administration, Xiao Chan, deputy director of the National Climate Center, introduced that the precipitation in northern China in 2021 will be the second largest in history, second only to 1964, and the annual precipitation in Beijing, Tianjin and Hebei will be the largest in history.

Talking about the reasons, he said that more precipitation in the north is affected by various factors, which are related to climate warming.

  Xiao Chan introduced that in the past 70 years, the main rain belts in China have been characterized by significant chronological changes.

From the 1950s to the 1970s, the rainbands were mainly located in the area north of the Yellow River, showing the characteristics of “floods in the north and droughts in the south”; since the 1980s, there were two rainbands in the north and south, one of which was located in the three northeastern provinces and northern Inner Mongolia, and the other A rain belt is located in the middle and lower reaches of the Yangtze River, that is, "southern floods and northern droughts"; in the past ten years, the rain belt has begun to show obvious characteristics of northward uplift and northward expansion.

  According to the Farmer's Daily report, many experts said that from the perspective of precipitation, although China has already experienced a trend of "the northward expansion of the rainfall belt", in general, the precipitation in the north is still lower than that in the south, and it should still be "less in the north and more in the south." However, the situation of periodic droughts in the south and floods in the north in certain time periods in individual years cannot be ruled out. The risk of drought in the south does exist.

  On August 30, the website of the Ministry of Water Resources announced that according to forecasts, the rainfall in the upper reaches of the Yangtze River in September was 10% higher than that of the same period of the previous year, which is beneficial to the relief of the drought, but the drought in some severely arid areas may still continue; The rainfall in the lake and Poyang Lake areas is 20% to 50% lower than that of the same period of the previous year. The main stream of the middle and lower reaches of the Yangtze River and the rivers of the two lakes have less water, and the water level continues to decline. The drought may further develop and the drought resistance situation is still severe.