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A calibrated, coupled model of the Bohai and Yellow Seas is developed to investigate sediment transport and deposition processes around a distinct clinoform east of the Shandong Peninsula. On the clinoform, deposition patterns vary seasonally with the regional hydrography and the East Asian Monsoon. A local maximum in sediment deposition is located offshore from spring to autumn, whereas sediment deposition is greater near the coast and decreases seaward in winter. From spring to autumn, a thermal front develops around the Yellow Sea Cold Water Mass and limits sediment transport seaward, enhancing sediment deposition and leading to high deposition rate in a focused region offshore. Sediment is transported to the region by the southward basin-scale cyclonic circulation, and the cross-shelf gradient in stratification, sediment resuspension, and vertical mixing at the front lead to a convergence in sediment transport and deposition. Sediment deposition over the clinoform is the greatest during the transition from summer to autumn when the thermal front persists but sediment supply increases. This results from weakened stratification and greater resuspension near the coast due to stronger winds, waves, and sea-surface cooling. A seasonal seaward shift of the frontal position toward deeper water is consistent with the decreasing heat flux, and the corresponding shift in location of maximum sediment deposition shifts seaward. In winter, the thermocline disappears and vertical mixing increases throughout the region. SSC over the clinoform increases due to active resuspension and net deposition decreases, and instead sediment is transported seaward and deposits in the South Yellow Sea. Current velocity, SSC and sediment deposition rates decrease seaward, in contrast to the focused trapping at the thermal front from spring to autumn. The deposition rates around the thermal front from spring to autumn are greater than in the winter, so the high net sediment accumulation over an annual cycle occurs in the same region as the longer-term accumulation preserved in the omega-shaped clinoform. • Sediment deposition rates are increased at a thermal front from spring to autumn at east of the Shandong Peninsula. • Seasonal shifts of the position of thermal front and sediment depo-center broaden the sediment accumulation region. • The monsoonal climate plays a dominant role in the seasonally varying circulation and sediment transport in the Yellow Sea. [ABSTRACT FROM AUTHOR]

Wang, A. M.; Wang, H. J.; Bi, N. S., and Wu, X., 2016. Sediment transport and dispersal pattern from the Bohai Sea to the Yellow Sea. Suspended sediment flux, dispersal patterns and its possible mechanisms in the Bohai Sea were investigated based on the observational data in May and November, 2012, data retrieved from MODIS imageries and the ocean current data from HYCOM. The sediment dispersal pattern and the annual net sediment flux presented evident seasonal variability. During wintertime, the prevailing strong northerly winds and the related high wave heights resuspended the sediment along the coast of the Huanghe Delta that was transported into the Laizhou Bay along its western coast and exported to the Bohai Strait through the eastern Laizhou Bay as enhanced by the coastal current. The wintertime contributed approximately 4.84 Mt of suspended sediment flux to the Yellow Sea, as higher than the flux in summertime by one order. In summertime, the less energetic environment together with the stratified water column was unfavorable to the sediment export to the Yellow Sea. As a result, the sediment delivered by the Huanghe to the sea in summertime mostly accumulated within the subaqueous delta, which acted as a primary source of sediment export to the Yellow Sea in wintertime. [ABSTRACT FROM AUTHOR]

Distribution of suspended sediment in the Bohai Sea and its seasonal variability were investigated based on the datasets obtained from four cruises carried out in different seasons in 2010 and 2012. The results indicate that the spatial distribution of suspended sediment in the Bohai Sea was dominated by the river input and coastal resuspension that depends on the type of local surface sediment and hydrodynamics. The suspended sediment was mostly concentrated in the southern Bohai Sea particularly around the Yellow River Delta in the summer season as impacted by the river plume but confined within a very limited area near the river mouth, whereas in winter–spring seasons sediment concentration became much higher as a result of active coastal resuspension induced by energetic wave actions in the shallow water. High sediment concentration was found in Liaodong Bay in winter–spring seasons when dynamics become strong but decrease significantly in summer seasons. The sediment concentration in the southern Bohai Strait was much higher than that in the northern part, suggesting evident sediment export to the Yellow Sea particularly in the winter–spring seasons. Strong seasonal variability of suspended sediment distribution in the Bohai Sea was consistent with the monsoon activity and associated wave actions and coastal currents that are varying seasonally. The dominance of seasonal monsoon signal and associated wave dynamics make the subaqueous Yellow River delta to be a major sink for the terrestrial sediment in the summer seasons, but transiting to a primary source in winter–spring seasons for sediment redistribution in the Bohai Sea and sediment export to the Yellow Sea. The seasonal patterns of suspended sediment distribution in the Bohai Sea and the dominance of monsoon activities may provide a good reference to understanding the sediment transport in the China Shelf Seas where sediment resuspension and coastal circulation are evidently driven by monsoon. [ABSTRACT FROM AUTHOR]