Improving Remote Sensing of Aerosol Optical Depth over Land by Polarimetric Measurements at 1640 nm: Airborne Test in North China

Remote Sensing

Bin Sun¹  Xiaobing Sun¹  Yanli Qiao¹  Han Wang¹  Zhao Liu²  Wei Huang²  Zhengqiang Li²  Lili Qie²  Xingfeng Chen²  Weizhen Hou²  Donghui Li² 

[1] Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031 , China;State Environmental Protection Key Laboratory of Satellite Remote Sensing,Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100101, China;

关键词: aerosol optical depth (AOD);    polarized surface reflectance;    1640 nm;    airborne Advanced Multi-angle Polarized Radiometer (AMPR);   

DOI  :  10.3390/rs70506240

来源: DOAJ

【 摘 要 】

An improved aerosol retrieval algorithm based on the Advanced Multi-angular Polarized Radiometer (AMPR) is presented to illustrate the utility of additional 1640-nm observations for measuring aerosol optical depth (AOD) over land using look-up table approaches. Spectral neutrality of the polarized surface reflectance over visible toshort-wavelength infrared bands is verified, and the 1640-nm measurements correctedfor atmospheric effects are used to estimate the polarized surface reflectance at shorter wavelengths. The AMPR measurements over the Beijing-Tianjin-Hebei region in north China reveal that the polarized surface reflectance of 670, 865 and 1640 nm are highly correlated with correlation slopes close to one (0.985 and 1.03) when the scattering angle is less than 145°. The 1640-nm measurements are then employed to estimate polarized surface reflectance at shorter wavelengths for each single viewing direction, which are then used to improve the retrieval of AOD over land. The comparison between AMPR retrievals and ground-based Sun-sky radiometer measurements during three experimental flights illustrates that this approach retrieves AOD at 865 nm with uncertainties ranging from 0.01 to 0.06, while AOD varies from 0.05 to 0.17.

【 授权许可】

Unknown