东亚沙尘源地、沙尘输送路径的遥感研究

东亚沙尘灾害严重影响东亚各国的生态环境 ,在源地大量侵蚀表层土壤 ,在输送过程中严重污染大气环境质量。此外 ,作为气溶胶 ,对区域辐射平衡和天气系统产生重大影响。本文利用 Sea Wi FS遥感数据分析了东亚沙尘灾害的源地、沙尘输送路径 ,结果显示 :东亚沙尘的三个主要源地是蒙古的戈壁、内蒙古中西部的沙漠戈壁和塔克拉玛干沙漠。沙尘输送路径有北路、中路和南路三条 ,北路主要影响中国的东北地区 ,中路主要影响中国的华北地区 ,南路主要影响中国的华中、华东地区。通过遥感确定沙尘源地和沙尘输送路径对于东亚沙尘灾害的治理有指导意义 ,也是对沙尘大气模式的一种检验。

Remote Sensing Study of Tracks and Source Areas of Eastern Asian Dust

Eastern Asian dust has great influences on ecosystem and atmosphere environment. The remote sensing data of 'true color' SeaWiFS image (7 months' daily data from Dec,2000 to Jun,2001 ) is used to analyze the source areas and tracks as well as temporal-spatial distribution of eastern Asian dust. The result indicates that three main dust sources are Gobi of Mongolia, desert and Gobi of inner Mongolia, and Taklamakan desert. There are three tracks of eastern Asian dust according to difference of affected areas, that is, north track, middle track and south track. And the north track affects the northeastern China, the middle track affects northern China, and the south track affects eastern China. Based on the statistics of 7 months' daily SeaWiFS data, this paper find that Asian dust occurs most frequently in spring, especially in April. As dust sources, Taklamakan desert has 80 dust days, desert and Gobi of inner Mongolia has 19 dust days, and Gobi of Mongolia has 13 dust days. But not all dust occurred in dust sources moves away to the outside. Moreover, as dust affected areas, northeastern China has 19 dust days, northern China has 20 dust days, and eastern China has 10 dust days.