On the internet, some netizens put forward the theory of "Three Gorges induced drought", saying that the Three Gorges Project is the chief culprit of this year's rare drought in the middle and lower reaches of the Yangtze River.
In response to the "Three Gorges induced drought theory", some well-known experts and scholars in meteorology, geology, water conservancy and other fields said that there is no evidence to support the "Three Gorges induced drought in the Yangtze River" theory.
Liu Min, director of the Wuhan Regional Climate Center of Hubei Meteorological Bureau, who has been monitoring the impact of the Three Gorges on climate for a long time, said that the current means and observation data have no basis to show that the Three Gorges Project triggered the drought in the middle and lower reaches of the Yangtze River.
"This drought is a cyclical climate phenomenon, mainly affected by atmospheric circulation. From the monitoring data, the impact on regional temperature and humidity before and after dam construction is also very weak. " Liu Min said.
According to reports, the environmental impact report of the Three Gorges Project on the Yangtze River scientifically analyzes the climate problems after the formation of the Three Gorges Reservoir. The basic conclusion is that after the completion of the Three Gorges Reservoir, the influence range of temperature, humidity, wind and fog in the reservoir area and its adjacent areas will generally not exceed 10 km.
Liu Min said that due to La Nina phenomenon, the northwest airflow is dominant. This year, the cold air frequently went south, which also suppressed the warm and humid airflow in the north, and it has been difficult to form continuous precipitation. This has also caused less rainfall in most parts of the middle and lower reaches of the Yangtze River since last June 165438+ 10.
On 24th, Zheng Shouren, chief designer of Three Gorges Project, chief engineer of Yangtze River Water Conservancy Commission and academician of China Academy of Engineering, responded to the "Three Gorges Drought Theory". He said: "Whenever we encounter extreme weather, we can't blame the Three Gorges Project. On the contrary, without the Three Gorges Project, the drought in the middle and lower reaches of the Yangtze River will intensify. "
According to Zheng Shouren, according to the design, the Three Gorges Reservoir starts to store water at the end of the flood season of the Yangtze River every year, and releases the water in the following dry season to replenish water for the middle and lower reaches of the Yangtze River. "Since June 5438+ 10 this year, the inflow released by the Three Gorges Reservoir is higher than the natural runoff of the Yangtze River, especially when there is a severe drought in the downstream, the reservoir discharges at a flow rate of 8,000 to 1 0,000 cubic meters per second, which is at least 2,000 cubic meters higher than the natural inflow."
According to the hydrological records of the Three Gorges Cascade Dispatching and Communication Center of the Three Gorges Project, the water level of the Three Gorges Reservoir has dropped from the highest175m to152.7m on 24th. "In this water level range, the original storage capacity of the Three Gorges Reservoir is about 654.38+073 billion cubic meters, which has been released to the middle and lower reaches." Zhao Yunfa, deputy chief engineer of the ladder dispatching center, said.
It is understood that the Three Gorges Reservoir will replenish about 300 million cubic meters of water every day after increasing the discharge flow at the request of the National Defense General on May 20 to support the drought relief in the middle and lower reaches. At present, the water level of hydrological stations in the middle and lower reaches of the Yangtze River has obviously rebounded.
In order to support drought resistance, the water replenishment process of the Three Gorges Reservoir will last until June 10 when the Yangtze River flood season comes.
Bianhe Town, Jianli County, Jingzhou City is a small town located in the middle reaches of the Yangtze River. A canal was built to divert water from the Yangtze River to irrigate farmland. After the Three Gorges increased the discharge, the drought-resistant situation in the whole town was effectively improved.
"After the water level rises, it becomes much easier for the pump to take water. At present, the water level of the Yangtze River is only 1 meter away from the canal intake. If the water level rises a little, there is absolutely no need to pump irrigation. " Pan Kejian, vice mayor, has high hopes for the drought-resistant function of the Three Gorges Project.
Pan Kejian believes that the advantages of the Three Gorges Project outweigh the disadvantages. "1998 There was a big flood in the Yangtze River. At that time, the Three Gorges Project had not been repaired. Jingzhou is in a hurry. After the completion of the Three Gorges, especially the flood last year, the flood control situation in Jingzhou has improved. "
Facing the public's doubts, Cao Guangjing, chairman of China Three Gorges Corporation, who is in charge of the operation and management of the Three Gorges Project, said in an exclusive interview with reporters on the 24th that since the impoundment of the Three Gorges Project, the Three Gorges Project has been taking measures to minimize the ecological impact of the Three Gorges Project.