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The Pearl River Estuary is the core water area of the Greater Bay area of Guangdong, Hong Kong, and Macao. The river net of the Pearl River Delta is dense and staggered, and its sediment transport process is complex due to the influence of runoff and tides. While sediment transport is a key process in river evolution, it is directly related to the flood control water supply and shipping safety of the Greater Bay area. To investigate the extent of the effect of sediment transport on the Greater Bay area, we analyzed the inversion of water surface sediment under tidal action using in-situ data, high-frequency GF-4 satellite image data (including multi temporal images), water quality, and reflection spectrum data from December 28, 2019 and June 20, 2020. The Mean Absolute Percentage Error (MAPE) value for atmospheric correction was 18.85%. We built several sediment inversion models based on the near-infrared, red, and blue band ratio of the GF-4 satellite image data. The best suited models for the flood and dry seasons had MAPE errors of 30% and 23.54%, respectively. We further obtained the continuous dynamic monitoring results and the daily change of sediment transport in the Pearl River Estuary at an interval of 2 h. The high frequency remote sensing inversion results gave a clear picture of the overall sediment transport dynamics of the estuary. Compared with the in-situ sediment concentration, the inversion results were consistent with the variation of sediment concentration in the tidal cycle. Moreover, we analyzed the dynamic characteristics of sediment transport under the influence of runoff tide. We found that with the rising tide, the overall suspended sediment concentration in Lingding Bay decreased considerably, Lingding Bay is a trumpet shaped estuary located outside the Pearl River Estuary. The north area of Neilingding Island is affected by human activities, thus the riverbed is degraded owing to reduced sediment input and reduced sediment resuspension to the surface. This creates a large water area of low suspended sediment content under the rising tide. Under the ebb tide, water with high suspended sediment content diffuses into the Macau Coastal Waters along the west bank of Lingding Bay. However, the southeast sediment diffusion is restricted by the backwaters from the Humen ebb current. Our method provides a new approach for large-scale operational monitoring of sediment transport in complex estuaries; furthermore, it provides a new strategy of cross-validation between the numerical simulation and remote sensing monitoring of sediment transport. [ABSTRACT FROM AUTHOR]