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The Bohai Sea is the receiving basin of the Yellow River (Huanghe), one of the largest contributors of global terrestrial materials to the sea. An area of fine-grained sediment deposition extends northeast of the Yellow River and its formation mechanism is still unclear. A calibrated, high-resolution coupled model of the Bohai and Yellow Seas was used to investigate sediment transport pathways in the region under the influence of strong and varying winds in winter. Numerical results highlight the importance of storm events in modifying the regional sediment resuspension and transport. During winter, the prevailing winds are typically from the northeast and northwest, interspersed by relaxation periods with weak winds. Winds influenced the currents and sediment movement in the Bohai Sea through several processes: local wind waves and resuspension, coastal-trapped waves in the Bohai Sea, and remotely forced coastal-trapped waves in the Yellow Sea. During northwesterly winds, sediment off the Yellow River Delta was mainly transported eastward along the south coast of Bohai Sea and escaped the Bohai Sea through the southern Bohai Strait. When northeasterly winds prevailed, sediment transport split into three branches: westward into the Bohai Bay, northeastward to the central Bohai Sea, and eastward along the south coast of Bohai Sea. Modeling results driven by synoptic winds indicate a more complex sediment transport pattern than previously understood with monthly average wind forcing. These findings challenge the traditional view of predominantly eastward sediment transport during winter and help to explain the observed grain size distribution in the Bohai Sea, in particular the accumulation of fine-grained sediments northeast of the Yellow River. • Storms are important in modifying the regional sediment resuspension and transport. • Sediment movement in BS depends on local winds, its related CTWs and CTWs in YS. • The formation of muddy areas northeast of the YRD is related to the varied winds. [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]