中国典型气溶胶模型光学特性分析及在大气校正中的应用

Optical Property Analysis of Typical Aerosol Models in China and Their Application in Atmospheric Correction

针对中国区域内卫星影像大气校正中气溶胶模型的适用性问题,基于Lorenz-MIE理论,结合多角度偏振相机(DPC)的3个观测通道,分析了中国典型气溶胶模型的光学特性,并将其出现频率较高(>5%)的模型组合用于可见短波红外高光谱相机(AHSI)观测仿真数据的大气校正中。通过对比校正结果,得到如下结论:在大气较为清洁的情况下,适合应用城市污染型与夏季粉煤灰型的模型组合或二次污染型与夏季粉煤灰型的模型组合,对中国区域内卫星影像进行大气校正;在气溶胶光学厚度较大(或能见度较低)时,华北、华南和西北区域内卫星影像大气校正中二次污染型与夏季粉煤灰型的模型组合更为适用,华东区域则是城市污染型与夏季粉煤灰型的模型组合更适合。

The optical properties of typical aerosol models in China are analyzed to solve the applicability problem of aerosol models for the atmospheric correction of satellite images in China.The Lorenz-Mie theory is used,combining with three observation channels of the directional polarization camera(DPC).The model combination with a higher frequency(>5%)is used in the atmospheric correction of simulation data observed by the advanced hyper-spectral imager(AHSI).From the comparison of the atmospherically corrected results,the following conclusions can be drawn:under the condition of relatively clean atmosphere,it is suitable to apply the combination of the urban polluted(F-ULW)model and the summer fly ash(C-ULW)model or the secondary polluted(F-BLW)model and the C-ULW model to the atmospheric correction of satellite images in China;when the aerosol optical thickness is large(or the visibility is low),the combination of the F-BLW model and the C-ULW model is more suitable for the atmospheric correction of satellite images in North China,South China,and Northwest China,while the combination of the F-ULW model and the C-ULW is more suitable for the atmospheric correction of satellite images in Eastern China.