自20世纪50年代艾比湖湖面面积急速退化造成大面积湖底裸露,裸露的干涸湖底成为丰富的粉尘和盐尘源,使得该地区面临严重的盐尘灾害威胁.为了研究艾比湖流域盐尘灾害对区域大气污染状况以及盐尘气溶胶光学性质,利用MODIS气溶胶产品数据获取2002年至今该地区尘暴总体演变态势;利用云-气溶胶偏振雷达(CALIOP)遥感数据以及Microtops II手持太阳光度计,对盐尘灾害高发时间段大气气溶胶总后向散射系数、退偏比、色比、气溶胶光学厚度(AOD)及Angstr(o)m波长指数(α)等参数进行特征分析,利用拉格朗日混合扩散模型(HYSPLIT)讨论盐尘污染的输送.实验结果表明:受大风天气和人类活动影响,春季是艾比湖流域盐尘灾害高发时段;盐尘灾害发生时,粉尘影响范围主要集中在近地面低空,对近尘源区的精河县、托托乡和乌苏市等地区造成较大影响;风速是影响局地气溶胶变化的主要因素,在局地尘源介入的影响下,距干涸湖底不同距离的地区气溶胶光学性质存在一定差异;盐尘主要在近尘源地区沉降,部分粉尘颗粒上升至高空大气,可对华北地区造成影响.地基和卫星遥感技术相结合,可实现区域气溶胶光学特性的准确估算,为认识盐尘灾害提供科学参考.%In the past 50 years,the Ebinur Lake had deteriorated rapidly.The dry lake became a rich source of dust and salt,causing the region to face serious threat of salt dust disaster.At present,studies on salt dust pollution focus on conditions for salt storms,wind erosion intensity of Lake Bottom,and dust fall flux.Few studies investigated the regional air pollution caused by salt dust storms and the optical properties of salt dust aerosols.The temporal variability,vertical distribution,and potential diffusion characteristics of salt dust in Ebinur region were investigated using the ground-based and satellite remote sensing and its potential diffusion characteristics were analyzed using the HYSPLIT model to learn more about aerosol optical properties.The aerosol product data provided by the MODIS were used to obtain the overall evolution trend of dust storms in Ebinur Lake Basin.CALIOP data provided the vertical distribution of aerosol including total attenuated backscatter coefficient,volume depolarization ratio,and color ratio.The AOD and Angstrom exponent obtained by Microtops Ⅱ sun photometer observations at the Jinghe and Wusu sites were used to investigate the aerosol properties in salt dust storms.The HYSPLIT model was used to simulate the salt dust diffusion trajectory of Ebinur Lake in spring.The degradation of the lake was the main reason for the occurrence of soil salinization and salt dust storms in Ebinur Lake Basin.The influence range of salt dust disaster in Ebinur region was mainly concentrated in the southeast of Ebinur Lake.The most active period of salt dust release and transportation was in spring.Salt dusts were mainly settled in Jinghe area,which was close to the dry lake bottom.The particle size of the aerosol particles in the atmosphere decreases,and the particle size increases with the increase in the distance from the dry lake dust source area.Thus,the area,which was far from the dust source,was not only affected by the Ebinur Lake salt dusts,but was also affected by the local dust source intervention.In the spring,the atmospheric aerosols were mainly in the form of coarse mode,and the dust aerosols were the main factor.The wind speed was the main factor affecting the local aerosol.Salt dust aerosols were mainly concentrated in the range of 0-2 km.The depolarization ratio was 10％-20％,the cumulative frequency was 28.538％,the color ratio was 0.4-0.8,and the cumulative frequency was 51.378％.With increasing height,the irregularity and size of the aerosol decreased,and little possibility was observed for the dust particles to be transported in other areas at high altitude.The aerosol particles mainly showed hydrophobicity when the dust storm occurred.However,aerosol particles,which are affected by the local aerosols,also showed a certain degree of hydrophilicity.The potential diffusion path to the eastern regions mainly affects Jinghe,Wusu,Kuitun,Shawan,Shihezi,Changji,Urumqi,Hami as well as Gansu,Inner Mongolia,Mongolia,Hebei,Liaoning,and other regions.The combination of ground-based and satellite remote sensing techniques to estimate regional aerosol optical properties can provide a scientific reference for the comprehensive understanding of salt dust disasters.
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