Influence of Three Gorges Dam Construction on Yichang Climate

It has a serious impact on the climate in China.

1. The impoundment of the Three Gorges has enlarged the surface of Gaoxia Lake from Chongqing to Yichang, and increased the upward water vapor flow in this area. This vertical upward air flow prevented the Siberian cold air, which is of great significance to China's climate, from going south and the Pacific warm and humid air flow from going north, and the original balance of climate laws was broken.

2. In winter, the warm and humid air flow in the Pacific Ocean is blocked from moving northward, and a large number of them gather in southern central China, southern Chongqing, Guizhou, northern Guangxi, Hunan and Hubei, northern Fujian, and most of western Zhejiang, resulting in an increase in the frequency of winter frost and snow disasters in this area. However, in the northern Qin-Ba mountain area, northern Sichuan, Henan, Shaanxi and Gannan areas, the warm and humid airflow that can form rainfall is obviously reduced in winter, which is characterized by high temperature and drought in winter.

3. In summer, the cold air in northern Qinba Mountain, northern Sichuan, Henan, Shaanxi, Gannan, southern Siberia and the rising water vapor of the Three Gorges produced more rainfall, while drought occurred in Central China, South China, East China, Chongqing and Guizhou.

In the case of drought, the Three Gorges will certainly open the floodgates to release water. As the lake surface shrinks, the upwelling airflow above will temporarily decompress and sink, creating strong convection opportunities for cold air in the south and warm and humid airflow in the north. Therefore, the violent alternation of drought and flood in a region is likely to be a disaster that needs attention in the future.

The Three Gorges reservoir area is an important part of the economic belt in the upper reaches of the Yangtze River, the ecological environment barrier in the middle and lower reaches of the Yangtze River and the focus of ecological environment construction in the west. It is an important power supply base and inland shipping trunk area in China, and has a very important strategic position in promoting economic development along the Yangtze River, economic exchanges between the east and the west and the development of the western region. The Assessment Report on the Impact of Climate Change in the Three Gorges Reservoir Area of the Yangtze River, edited by Cai Qinghua and others, is written by more than 20 experts with rich theoretical and practical experience in the research of the Three Gorges Reservoir Area, organized by the National Climate Center of China Meteorological Bureau, through a large number of data collection, summary and the author's existing achievements. The report is based entirely on the existing results. This book does not stick to the unified division of time and space. Its purpose is to expound the facts and impacts of climate change in the Three Gorges reservoir area, put forward adaptation and mitigation countermeasures according to local conditions, and provide theoretical basis and scientific and technological support for the sustainable development of social economy in the Three Gorges reservoir area under the background of global climate change. The Assessment Report on the Impact of Climate Change in the Three Gorges Reservoir Area of the Yangtze River is also the first research achievement on the vulnerability and adaptability of climate change at the basin scale in China.