干旱区生态环境知识资源中心

The observation of atmosphere dust in China's desert show that there is a continuous dust layer always existed in tower atmosphere under the height of 5 km. The dust concentration in the layer is changed with altitude and season. According to the Lidar data analysis the backscattering ratio value changes in the range of 2.5-5.5 in cleat weather. The higher value of the ratio can be extended to the height about the height of 3.5 km. The dust concentration is reduced sharply over 3.5 km. In the range of 15-20 km height, an aerosol layer is often observed in Shapotou region. The maximum backscattering ratio usually appears in 15-18 km. The value is approximately 1.2.