Estimating suspended sediment concentrations in a shallow estuary from MODIS red-channel reflectance (MODIS estimated suspended sediment concentration) (2011)
Haihong Zhao, Qin Chen, Nan D. Walker, Quanan Zheng, and Hugh L. Macintyre
The study utilized the Moderate Resolution Imaging Spectroradiometer (MODIS) red-channel reflectance with a spatial resolution of 250m to estimate a suspended sediment concentration (SSC) in the Mobile Bay estuary, Alabama. Based on monthly in situ sampling, a new algorithm was developed using an exponential regression model. SSC in Mobile Bay and Mississippi Sound was mapped by applying the new algorithm. The SSC maps during a cold front passage have revealed how the resuspension and transport of sediments respond to the variable wind forcing in the micro-tidal system. Particle tracking based on a three-dimensional hydrodynamic model was utilized to explain what was observed from the satellite imagery. It has been found that the rapid disappearance of the surface SSC after a cold front passage was mainly caused by settling of sediments rather than flushing out of the estuary. The study demonstrates that a combination of SSC mapped from the MODIS band-1 reflectance and three-dimensional numerical modeling is an effective tool to analyze sediment dynamics in the Mobile Bay estuary and other similar estuaries.