黄土高原半干旱地区MODIS反演气溶胶算法的地表反射率关系研究

Study of the Surface Reflectance Relationships Used in MODIS Retrieval Algorithm of Aerosols over the Semi-Arid Region of the Loess Plateau

参照MODIS遥感陆地上空气溶胶第二代算法(C005-L),利用黄土高原半干旱地区(AERONET)(兰州大学半干旱气候与环境观测站,SACOL)的实测资料,基于6S大气辐射传输模式,分别用构建的SACOL气溶胶模型和6S的大陆型气溶胶模型对MODIS/Terra资料进行大气订正,得到了SACOL区域春季可见光通道和近红外通道的地表反射率以及0.66vs2.12和0.47vs0.66地表反射率简单关系式,并验证了三个通道的地表反射率关系及其随散射角和植被指数的变化。结果表明,0.47vs0.66通道地表反射率关系比0.47vs2.12通道地表反射率关系的相关性和稳定性更大,0.47vs2.12地表反射率关系与散射角的相关性不大。

According to the second-generation（Moderate-resolution imaging spectroradiometer,MODIS） retrieval algorithm of aerosol properties over land（C005-L）,the atmospheric correction of MODIS/Terra data at Semi-arid climate and environment observatory of lanzhou university（SACOL） of（Aerosol robotic network,AERONET） in the semi-arid region of the Loess Plateau was performed by respectively using the SACOL aerosol model based on surface observation and the continental aerosol model used in 6S.The surface reflectances of the visible and near-infrared channels of the SACOL area were obtained and the 0.66vs2.12 and 0.47vs0.66 surface reflectance relation and their change with scattering angle and vegetation index were verified.The results show that the correlation of surface reflectances between 0.47μm and 0.66μm is stronger and more stable than the one between 0.47μm and 2.12μm; the surface reflectance relation of 0.47vs2.12μm is not dependent on scattering angle.