作者: Tian, LQ (Tian, Liqiao); Wai, OWH (Wai, Onyx W. H.); Chen, XL (Chen, Xiaoling); Li, WB (Li, Wenbo); Li, J (Li, Jian); Li, WK (Li, Wenkai); Zhang, HD (Zhang, Haidong)
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摘要: This study proposed a method for developing high spatial resolution Gaofen-1 satellite (GF-1) Wide Field Imager (WFI)-based total suspended matter concentration (C-TSM) retrieval model with the assistance of Moderate Resolution Imaging Spectroradiometer (MODIS) data, using the Deep Bay in China as a case. Based on long-term calibrated C-TSM measurements of optical backscatter (OBS) 3A turbidity and temperature monitoring system of two stationary stations from January 2007 through November 2008, 33 match-ups were selected to build an exponential retrieval model for MODIS atmospherically corrected remote-sensing reflectance (R-rs) ratio (R-rs,R-645/R-rs,R-555). Validation of the MODIS model showed well agreement with the seven in situC(TSM) measurements with a root mean squared error (RMSE) of 5.06mgl(-1) and a coefficient of determination R-2 of 0.80. Aided with six MODIS retrieved C-TSM products, different band combinations (single band (R-rc,R-660), band subtraction (R-rc,R-660-R-rc,R-560), band ratio (R-rc,R-660/R-rc,R-560), and total suspended matter index at 660nm band (TSMI660) were evaluated for simultaneous GF-1 WFI Rayleigh-corrected reflectance (R-rc). The results showed that the exponential model based on the Rayleigh-corrected reflectance ratio (R-rc,R-660/R-rc,R-560) could achieve acceptable accuracy, with RMSE of 14.80mgl(-1) and R-2 of 0.62. The proposed method would be helpful for dynamic monitoring in the Deep Bay, and more important could also provide an alternative approach for studies when in situ measurements are unreachable.
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