Geography teachers use graphs to analyze the effect of the Three Gorges on the regional climate

I am not an expert, but an ordinary high school geography teacher. I use my limited geographic knowledge to try to explain the impact on the climate after the construction of the Three Gorges Project. Please add anything wrong. The reservoir construction will change the local geographic climate, and the huge project such as the Three Gorges reservoir has a greater impact, especially when the Three Gorges is built in a region with special terrain and geology, there is no way to discuss the requirements.

Relatively speaking, high school students can easily understand this part of content.
Based on the formation of the Three-Ring circulation: low-latitude Circulation
Due to the high temperature in the equator, the air flow expands and increases, and the air pressure at high altitude is high. Due to the influence of the horizontal pressure gradient, the air flow flows to the Polar Direction. Due to the influence of the ground direction and partial force, when the airflow moves to 30 degrees north latitude, it will accumulate and sink, so that the surface pressure of the region is relatively high, and the region is located in the subtropical region, so the formation of subtropical high. The surface pressure in the Equator region is low, which forms the low pressure band of the equator. On the surface, the air flows from high pressure to low pressure to form a low-latitude circulation.
Mid-latitude circulation and high-latitude Circulation
On the earth's surface, the air pressure in the subtropical high area is high, so the airflow flows to the Polar Direction. In the polar region, due to the low temperature, the airflow shrinks and sinks, the air pressure is high, and the airflow flows towards the equator. The air flows from the polar region and the air flows from the subtropical region face each other near 60 degrees, forming a front, called a polar front. The airflow in this region is forced to rise, thus forming a polar low-pressure zone. After the airflow rises, it is diverted at high altitude and flows to the secondary and polar directions to form the Middle-latitude circulation and high-latitude circulation.
Therefore, the sinking air flow is controlled by the subtropical high near the north latitude 30 °. it is sunny and dry, and the world's major tropical desert is distributed around the north latitude 30 °.

However, the desert area near the 30 ° north latitude is only East Asia and Southeast North America, while East Asia is even more obvious. Why? There is monsoon circulation.

East Asia is located in the world's largest continent: continental Asia and the largest ocean: the Pacific Ocean. The thermal differences between oceans and land are the biggest, So India's low pressure occurs in the northwest of India in summer, the original subtropical high in the original band was interrupted, and the original Subtropical High was pushed to the ocean to form a Hawaiian high. In winter, the land temperature was low, the air flow sank, and a high pressure was formed near the ground, that is, the Mongolia-Siberian high pressure interrupts the original polar low-pressure belt to retreat to the ocean. The main summer in China is affected by the Hawaiian high pressure and the Siberian high pressure in winter.

Before the construction of the Three Gorges, the Hawaiian high pressure control pushed the warm and wet air flow on the Pacific Ocean to move from the southeast to the northwest, and formed a front when it was raining, the reality is the formation of the front rain. With the increase of Hawaii's high pressure and the weakening of Mongolia's Siberian high pressure, the rainfall belt will gradually move to the north. The design is the North-South Movement of China's summer monsoon, 3-5 months in the vicinity of the south ridge, arrived in the Yangtze River basin in June, arrived in North China in July, arrived in Northeast China in August.
After the construction of the Three Gorges, a huge water body was formed in the eastern part of the Sichuan Basin. During the water retention period, the dam height reached 175 meters, and the daily water storage reached 135 meters, in the middle and lower layers of the dam, the water temperature of the upper and lower layers is significantly different. The water temperature ranges from 5 to 10 degrees. That is, we talk about cold water and keep hot water. Day after day, a large amount of solar radiation is stored in the Sichuan Basin, heat increases the water temperature of the reservoir, water vapor evaporates, and the greenhouse effect of water vapor is several times that of CO2. After the dam is built in the Sichuan Basin, a relatively independent system is formed. The temperature is high, and the atmosphere expands by heat, low pressure is formed near the ground, such.

High pressure is easily attracted by low pressure. A new region with low pressure appears in the Three Gorges region. In the last four to eight months, the high pressure in Hawaii in the Pacific Ocean will be attracted to the west, under normal circumstances, the Hawaiian high pressure will cover China in. Now, due to the low pressure zone in Sichuan, the Hawaiian high pressure is pushed forward to the west, thus preventing the summer monsoon from moving north, rather than arriving in the Middle and Lower Reaches of the Yangtze River around June, there may be clear and dry weather. The rain belt lingers in the two regions.
When the temperature was low, after November, China was basically under control of the Siberian high pressure in Mongolia. The low-pressure areas in Sichuan would also become more attractive to the Siberian high pressure and change some directions, from the original northwest to the southeast region to a more southern region, as a result of the strengthening of the Siberian attraction, the actual Mongolia Siberian high pressure also increased, will make the winter snow belt south shift, in the past, the main winter snowfall belts were in Hunan, northern jiangxi, and Southern Hubei, and they continued to move south to the Nanling area. Will the snow disaster in the past 08 years be affected?

subsequent forecasts of climate change in China:
1 the frequency of drought in the Middle and Lower Reaches of the Yangtze River and the upper and lower reaches of the Yangtze River will increase significantly
2 the rainfall in spring and summer in South China will increase, and the probability of heavy rain will increase.
3 in winter, in southern Hunan, the temperature in the two regions is lower than that in the past, and the snowfall increases.
4. The track of typhoon logon may change, and the possibility of typhoon moving westward increases. In Western Guangxi, the probability of a typhoon landing in northern Vietnam increases
5. Plum Rain in the Yangtze River is shortened or even disappears, and rainfall in southern Japan is affected
6. Drought in spring and summer may affect Southeast Asia.