利用GF-4 PMS数据反演城市地区气溶胶光学厚度

高分四号是我国发射的第一颗地球同步轨道卫星,具有较高的空间分辨率及快速重复成像能力,在城市大气环境的高动态监测方面拥有较大的应用潜力。针对城市地区地表反射率高、地表类型复杂,传统的单一算法较难实现大气气溶胶光学厚度有效反演等问题,以北京市为研究区,使用了一种暗目标法和地表反射率数据库相结合的方法,分别对2017年5月25日和10月5日两个时相的气溶胶光学厚度进行了估算。结果表明,该方法能够有效实现城市暗目标区和亮目标区的气溶胶反演,且与MODIS标准陆地气溶胶产品及AERONET站点地面观测数值较为一致,相关系数超过了 0.9。

Aerosol Optical Depth Retrieval over Urban Areas Using GF-4 PMS Images

GF-4 is the first geosynchronous orbit satellite launched in China,which has high spatial resolution and fast repetitive imaging ability,and has great application potential in the high dynamic monitoring on urban atmospheric environment.Due to the high surface reflectivity and complex surface types in urban areas,it is difficult to implement the effective inversion of atmospheric aerosol optical depth (AOD) by a single algorithm.In this paper,a method of combining dark target algorithm with surface reflectence database was used for Beijing city to estimate the aerosol optical thickness on May 25 and October 5,2017,respectively.The results show that this method can effectively retrieve the urban AOD of dark target area and bright target area,the retrieved AOD has a good correlation with MODIS standard land aerosol products (MOD04) and AERONET ground observation data,and the correlation coefficients reach more than 0.9.