Simulation of suspended sediment transport initialized with satellite derived suspended sediment concentrations

Abstract

Suspended sediment transport in the Gulf of Kachchh is simulated utilizing the suspended sediment concentration (SSC) derived from Oceansat OCM imagery, as the initial condition in MIKE-21 Mud Transport model. Optimization of the model mud parameters, like settling velocity and critical shear stress for erosion are realized with respect to the sediment size distribution and the bottom bed materials observed in the Gulf. Simulated SSCs are compared with alternate OCM derived SSC. The results are observed to be impetus where the model is able to generate the spatial dynamics of the sediment concentrations. Sediment dynamics like deposition, erosion and dispersion are explained with the simulated tidal currents and OCM derived sediment concentrations. Tidal range is observed as the important physical factor controlling the deposition and resuspension of sediments within the Gulf. From the simulation studies; maximum residual current velocities, tidal fronts and high turbulent zones are found to characterise the islands and shoals within the Gulf, which results in high sediment concentrations in those regions. Remarkable variability in the bathymetry of the Gulf, different bed materials and varying tidal conditions induces several circulation patterns and turbulence creating the unique suspended sediment concentration pattern in the Gulf.

Cohesive Sediment Transport Modeling on Inner Ambon Bay

“…Hal ini memungkinkan konsentrasi sedimen sebagian besar akan tetap berada di dalam TAD (Hermanto, 1987;Tuhumury et al, 2007). Secara umum konsentrasi sedimen semakin rendah saat menjauhi muara sungai (sources) dan menuju ke tengah atau keluar dari teluk (Ramakrishnan and Rajawat, 2012;Sravanthi et al, 2015).…”

Using GOCI Retrieval Data to Initialize and Validate a Sediment Transport Model for Monitoring Diurnal Variation of SSC in Hangzhou Bay, China

“…In the study area, the suspended sediments consist mainly of fine particulate material and very fine suspended sediments released by the Changjiang River and Qiantang River [25,[42][43][44][45][46]. Beginning with the reference settling velocity of 0.0002 m/s given by Ramakrishnan and Rajawat [8], a uniform particle sinking rate 0.0006 m/s for suspended sediments is arrived at after model calibration. This settling velocity is passed to the hydrodynamic model and particle sinking is implemented in the advection-diffusion equation through an additional advection term in the vertical transport equation.…”

“…But the usefulness of the numerical approach is strongly dependent on the knowledge of oceanic dynamic processes, the correct determination of key parameters in formulations and the quality of initial fields, etc. [8,9]. Therefore, one can combine satellite remote sensing with numerical models to improve the utility of the research for suspended sediment transport and outcomes in coastal waters.…”

Modeling and remote sensing of suspended sediments in the Gulf of Kachchh, India

“…Suspended sediments have a direct impact on the underwater light availability for primary production, coastal erosion, accretion, and transport of minerals and pollutants to the oceans [Eisma, 1981]. The usage of satellite remote sensing data for monitoring the dispersal and distribution of suspended sediments has proven to be useful because of high-temporal images (every alternate day) at spatial resolution of as high as 360 m available from the Ocean Color Monitor (OCM) [Pradhan et al, 2004;Rajawat et al, 2005;Ramakrishnan and Rajawat, 2012]. Satellite-based monitoring of suspended sediments is of significance because of its greater spatial and temporal coverage as compared to sea-or ground-truth observations.…”

“…OCM data have demonstrated its widespread utility in sediment dispersal dynamics studies [Pradhan et al, 2004], underwater bed forms, and sediment plume [Kunte et al, 2003]. OCM-derived SSC products can also be input to simulate and predict SSC in the GK [Ramakrishnan and Rajawat, 2012]. Chauhan et al [2007] used the improved spatial resolution of OCM data to find sources, sinks, and dispersal pathways of suspended sediments in the GK.…”