Retrieval of aerosol fine-mode fraction over China from satellite multiangle polarized observations: validation and comparison
Abstract. The aerosol fine-mode fraction (FMF) is an important
optical parameter of aerosols, and the FMF is difficult to accurately
retrieve by traditional satellite remote sensing methods. In this study, FMF
retrieval was carried out based on the multiangle polarization data of
Polarization and Anisotropy of Reflectances for Atmospheric Science coupled
with Observations from Lidar (PARASOL), which overcame the shortcomings of
the FMF retrieval algorithm in our previous research. In this research, FMF
retrieval was carried out in China and compared with the AErosol RObotic
NETwork (AERONET) ground-based observation results, Moderate Resolution
Imaging Spectroradiometer (MODIS) FMF products, and Generalized Retrieval of
Aerosol and Surface Properties (GRASP) FMF results. In addition, the FMF
retrieval algorithm was applied, a new FMF dataset was produced, and the
annual and quarterly average FMF results from 2006 to 2013 were obtained
for all of China. The research results show that the FMF retrieval results
of this study are comparable with the AERONET ground-based observation
results in China and the correlation coefficient ( r ), mean absolute error
(MAE), root mean square error (RMSE), and the proportion of results that
fall within the expected error (Within EE) are 0.770, 0.143, 0.170, and
65.01 %, respectively. Compared with the MODIS FMF products, the FMF
results of this study are closer to the AERONET ground-based observations.
Compared with the FMF results of GRASP, the FMF results of this study are
closer to the spatial variation in the ratio of PM 2.5 to PM 10 near
the ground.