利用可见光与近红外大气窗区的组合通道探测陆面上空气溶胶

摘要

A special method is proposed for remote sensing of aerosols over land through analyzing satellite-measured radiances reflected from the earth-atmospheric system at two shortwave atmospheric window channels of 0. 5 and 0.85 microns. Sensitivity tests reveal that the behavioral features of the differences (D) and ratios (R) between the refleeted radiances at these two channels with increasing aerosol optical depth are much different among different types of aerosols. Analyzing how D and R behave with varying aerosol optical depth can help us qualitatively distinguish aerosol types and quantitatively estimate their optical depth. in addition, it is also found that this method is feasible for the most common ground reflectance types.%本文提出了一种利用可见光与近红外大气窗区内的0.5μm和0.85μm双通道的组合,通过观测地气系统的反射辐射从卫星上遥感陆面上空气溶胶的方法.模拟试验发现,对于不同类型的气溶胶,随着气溶胶光学厚度的逐渐增大,0.5μm和0.85μm双通道的反射辐亮度的差值和比值呈现出明显不同的变化趋势,据此便可以识别出气溶胶的类型,并可进一步推算出其光学厚度.另外,模拟试验还发现,对于常见的几类地物反射率类型,该方法都是适用的.