资源环境科技发展态势分析平台

The geochemical analysis of sediment in the northern North Yellow Sea shows that the sediment derived from the Yellow River could penetrate the Yellow Sea Warm Current and mingle with Yalu River-derived sediment in coastal areas. Further analysis indicates that the relative variations in coastal currents and the Yellow Sea Warm Current, which are regulated by the winter monsoon, dominate the process of cross-front transport. This suggests a dynamic mechanism involving cross-front sediment transport. During a period of strong northwesterly wind, the sediment derived from the Yellow River north of the Shandong Peninsula could disperse across the fronts in the surface layer, and when the wind subsides, sediments are delivered northward by barotropic current. This dynamic mechanism for sediment exchange in the North Yellow Sea can explain the multiple sediment sources found in the Yellow Sea, and it has implications for cross-front transport on a global scale.

Plain Language Summary River input sediments are usually deposited in nearshore areas due to the restriction by coastal fronts. However, terrigenous sediments can be found in offshore areas or deep ocean. This implies that fronts cannot completely trap coastal sediment. Numerous dynamic processes can cause cross-front sediment transport, for example, water dilution, gravity flow, and fronts penetration. In this study, the occurrence of Yellow River-derived sediment in the southern coastal area of the Liaodong Peninsula indicated that cross-front transport could occur in this area. Based on the combined analysis of sea surface height and sea surface temperature, we found that the winter monsoon could weaken surface fronts and enhanced the intensity of coastal current. This facilitated coastal sediment transport to offshore areas during northerly wind, then onshore after the wind. Cross-front transport load should be considerable as the suspended sediment concentration in nearshore areas can remarkably increase during the winter monsoon that usually last for almost half a year.