Excuse me, what are the reasons for the differences in haze on the east and west sides of Taihang Mountains?
1. The eastern foothills of Taihang Mountains emit too much PM2.5 and other pollutants into the air
The basic reason for the formation of the haze belt in the eastern foothills of Taihang Mountains is the human activities in this area The total amount of PM2.5 and other pollutants emitted into the air (exhaust gas from vehicles and other vehicles, corporate exhaust gas and flying dust, etc.) is too much. Taking urban Beijing as an example, after a northwest wind blows clean air (PM2.5 value is below 50 points), the clean air can only last for about a day, because the value of new PM2.5 pollutants here is between 50 and 50 every day. Around 70 o'clock. In this case, as long as there are 2-3 consecutive days of calm weather, the urban area of Beijing will enter a state of severe pollution.
2. The tall buildings at the eastern foot of the Taihang Mountains are an important factor in causing stable weather
According to man-made terrain climatology, man-made tall buildings and huge building groups will, to a certain extent, Change the climate of the local and surrounding areas and even distant areas. This is because tall buildings and huge building complexes are essentially equivalent to new mountains and hills appearing on the earth. They will increase the surface roughness and thus increase the corresponding degree of wind resistance (the height range of their influence is 4-5 times the height of the building). ).
3. The water vapor stored in Taihang Mountain is losing
Taihang Mountain was originally a geomantic treasure land with dense forests and abundant water. This is recorded in the "Book of Mountains and Seas" and a large number of ancient books. The third mountain range in the "Wuzang Mountain Sutra - Beishan Sutra" describes the landscape of the Taihang Mountains 4,200 years ago. At that time, many water systems originated from the Taihang Mountains, and there were many large lakes in the North China Plain (see the 42-square-meter giant painting "Emperor Yu's Mountains and Rivers" and "Classic Illustrated Reading of the Classic of Mountains and Seas", "Dictionary of Appreciation of the Classic of Mountains and Seas", "Ten Days Talk about the Classic of Mountains and Seas" and other monographs). Since then, as the Yuan, Ming and Qing dynasties established their capitals in Beijing, a large number of trees in the Taihang Mountains were cut down for construction and heating. As a result, the original forest vegetation here was destroyed, and the amount of water flowing from the Taihang Mountains to the Bohai Sea was also reduced accordingly.
4. The amount of water vapor evaporating from the Bohai Sea is decreasing
Most of the water vapor stored in the Taihang Mountains comes from the water vapor evaporating from the Bohai Sea, and the carrier is the east wind blowing from the direction of the Bohai Sea. In addition, there is a small amount of water vapor transported by southerly, southeasterly, southwesterly and northeasterly winds. There is no doubt that the water vapor in the Bohai Rim region mainly depends on the evaporation of water vapor in the Bohai Sea; therefore, once the evaporation of water vapor in the Bohai Sea decreases, it will inevitably lead to a decrease in water resources in the Bohai Rim region. Or, conversely, the decreasing trend of water resources in the Bohai Sea region indicates that the evaporation of water vapor in the Bohai Sea is decreasing. The decrease in vapor evaporation from the Bohai Sea may also be one of the factors responsible for the formation of the haze belt at the eastern foot of the Taihang Mountains.