Geographical climate of Ji-Er Railway

The landform is dominated by the Mongolian plateau, with complex and diverse forms. The average altitude is about 1000 meters. Loess hills and stony hills are distributed at the junction of mountainous areas with high plains and plain, with low mountains, valleys and basins in the middle, which leads to serious soil erosion. It has a vast territory, developed strata, frequent magmatic activities, good metallogenic conditions and rich mineral resources. In Mesozoic and Cenozoic, influenced by the westward subduction of the Pacific plate, two famous grade II metallogenic belts appeared in China, which were located on the contact axis between these two main structural units and the third uplift belt of Neocathaysia. The former is grade II gold-copper polymetallic metallogenic belt in the northern margin of North China platform, and the latter is grade II copper polymetallic metallogenic belt in Daxinganling.

The climate is dominated by temperate continental monsoon climate. It has the characteristics of less and uneven precipitation, strong wind force and drastic changes in cold and summer. The general characteristics are sudden temperature rise in spring, windy, short and hot in summer, concentrated precipitation, sudden temperature drop in autumn, frost often comes early, long and cold in winter, and many cold waves. Annual solar radiation increases from northeast to southwest, and precipitation decreases from northeast to southwest. The annual average temperature is 0℃ ~ 8℃, the annual average temperature difference is 34℃ ~ 36℃, and the daily average temperature difference is 12℃ ~ 16℃. The annual total precipitation is 50 ~ 450 mm, with more precipitation in the northeast and less precipitation in the west. The precipitation in the eastern Oroqen Autonomous Banner is 486 mm, the annual precipitation in the Alashan Plateau in the west is less than 50 mm, and that in Ejina Banner is 37 mm The evaporation in most areas is greater than l200, the annual evaporation in Daxing 'anling is less than 1, 200mm, and that in Bayannaoer Plateau is greater than 3,200 mm. Inner Mongolia is abundant in sunshine and light energy resources. The annual sunshine hours in most areas are more than 2,700 hours, and those in the western part of Alashan Plateau are more than 3,400 hours. The annual average number of windy days is 10 ~ 40 days, of which 70% occurs in spring. Among them, Xilingol and Wulanchabu Plateau lasted for more than 50 days; The number of sandstorm days is 5-20 days in most areas, more than 20 days in western Alashan and Ordos Plateau, and the average daily gale of Huluchigute in Ejina Banner of Alashan League is 108 days.