Ministry Of Water Resources Officials: Local Drought Is A Natural Phenomenon &Nbsp, And Has Nothing To Do With The Three Gorges.

This year, the middle and lower reaches of the Yangtze River continued to suffer drought and some areas in recent years were violent. drought and flood The extreme weather events such as sharp turns have once again triggered the controversy over the pros and cons of the Three Gorges Project. Cai Qihua, director of the Yangtze River Water Resources Commission of the Ministry of water resources, said the Three Gorges project did not change the upper air weather situation in the basin.

Disaster cause

Extreme weather factors Global warming

Q is the continuous serious drought in the middle and lower reaches of Yangtze River and the current local flood caused by the Three Gorges reservoir?

Cai Qihua: the reason why the rainfall continues to be serious is due to the influence of the La Nina phenomenon in the equatorial eastern central Pacific (601099). Since this year, the atmospheric circulation system has been exceptionally prominent, the southern tropical system is weak, the cold air activities in the north are strong, and the water vapor spanport channel in the river basin has not been effectively established, resulting in a 40% less rainfall in the Yangtze River Basin.

The reason for the recent local flooding is that after June, the Yangtze River Basin is in the main flood season, and local heavy rainfall occurs in many places, resulting in the occurrence of local areas in many provinces and cities. Flood disaster But the main stream and main tributaries of the Yangtze River are stable. The reason for the four strong precipitation since June 3rd is the intersection of cold and warm air currents.

Q does the increase in extreme weather events in the Yangtze River Basin mean that the Three Gorges project is changing the upper air weather situation in the basin?

Cai Qihua: in recent years, global warming is an indisputable fact, which has led to frequent occurrence of extreme weather events. Judging from the weather causes, the main cause of extreme weather events is the change in altitude from the ground to about 5500 meters. The dam height of the Three Gorges dam is only 185 meters, which is a trace relative to the 5500 meters and will not affect the upper air weather situation in the Yangtze River Basin. In some areas, severe drought is a natural phenomenon occurring in the extremely dry season, which has nothing to do with the Three Gorges reservoir. Evaporation of large water storage projects may increase humidity in the surrounding area due to water evaporation, which is a positive effect on drought.

Pros and cons

The advantages and disadvantages of the project are fully certified.

Q how can we evaluate the advantages and disadvantages of the Three Gorges Project?

Cai Qihua: the construction of the Three Gorges project has more advantages than disadvantages. Flood control can effectively control the upstream flood. The flood control standard of Jingjiang reach can be raised from 10 years to 100 years. Last year's flood season, faced with the largest flood in the past ten years, the Three Gorges project has accumulated about 26000000000 cubic meters of flood water.

The discharge capacity of the Three Gorges Reservoir in dry season is larger than that in natural conditions, which is beneficial to improving the water environment and water supply conditions.

Has Q assessed the drawbacks of the Three Gorges Project and formulated corresponding solutions?

Cai Qihua: the possible adverse effects on the Three Gorges project, including the impact on the environment and ecology, the prevention and control of geological disasters in the reservoir area, and the protection of water environment, have been fully demonstrated in the Three Gorges demonstration stage, and a solution has been put forward in the design stage. During the construction period, the corresponding engineering construction has been completed according to the design.

After the completion of the operation, the optimal operation is carried out according to the operation of the project. At the same time, the problems brought about by the upstream and downstream areas have been seriously studied, and corresponding governance has been carried out to make the project more profitable and less harmful and long-term stability.