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The high-resolution multi-mode imaging satellite called GFDM (Gao Fen Duo Mo) has been successful launched in July 3 of 2020, which was integrated with 1 panchromatic and 8 multispectral bands with the spatial resolution of 0.42 m and 1.6 m, respectively. The Synchronization Monitoring Atmospheric Corrector (SMAC) instrument was also on board GFDM satellite, aiming for offering time synchronized and field of view overlapped atmospheric measurements to improve the atmospheric correction of the GFDM main sensor image. As the first civilian atmospheric corrector onboard high spatial resolution satellite with polarization detection, SMAC has 8 wavelength bands from visible to short-wave infrared with the spatial resolution about 6.7 km. In order take full advantage of the multispectral measurements of SMAC, we investigate to retrieve the aerosol optical depth (AOD) by using the intensity measurements in this study. To decouple the surface-atmosphere contribution from SAMC measurements, the corresponding surface reflectance over land is derived from the Moderate-resolution Imaging Spectroradiometer (MODIS) surface bi-directional reflectance climatology. Based on the principal component analysis method and the dataset from spectral libraries, the surface reflectance ratios are further obtained by spectral conversion with the spectral response function from MODIS to SAMC for aerosol retrieval. With the aerosol look-up table (LUT) established by the Second Simulation of the Satellite Signal in the Solar Spectrum (6S) radiation transmission model, the multispectral inversions are carried out and the AODs are retrieved. In addition, the AOD data from Aerosol Robotic Network are used to validate the retrieved results from SAMC by the spatial-temporal matching, the statistical parameters including the root mean square error (RMSE) and the correlation coefficient (R) are employed together. By this means, the retrieved AODs from the intensity measurements of SAMC are preliminary investigated.
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