| Autor: |
Gong, Wenping1,2,3, Chen, Lianghong2,3, Zhang, Heng1,2,3, Yuan, Lirong1,2,3, Chen, Zhaoyun4 chenzy@stu.edu.cn |
| Předmět: |
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| Zdroj: |
Journal of Geophysical Research. Oceans. Feb2020, Vol. 125 Issue 2, p1-25. 25p. |
| Abstrakt: |
River plumes are important pathways for the transportation of terrigenous materials to coastal oceans. This study uses the Regional Ocean Modeling System to investigate the dynamics of a small river plume from a lateral river tributary discharging into an estuary. In particular, the plume is surface advected under buoyancy force alone, and the Earth's rotation helps to increase the plume's spread in a downstream‐biased pattern. Adding tides to the model changes the plume into a bottom‐advected one, and the plume is advected in an alongshore direction, with its spreading more upstream biased. Tide‐induced mixing and tidal advection are responsible for the changes in the plume structure, especially the tidal asymmetry between ebb and flood tides; the tidal residual circulation is insignificant. When river discharge from the estuary head is imposed, the plume is forced to propagate downstream extensively. This study offers insights into the transport and fate of riverine materials in tributaries that flow into semienclosed waterbodies. Plain Language Summary: A lateral river plume discharging from a tributary into an estuarine water body is widely observed in the world. How the river discharge from the estuary head impacts the dynamics of the lateral river plume is not sufficiently explored. The Pearl River Estuary is taken here as an example, which features lateral tributary river inflow. The dynamics of the lateral river plume are not only influenced by the Earth's rotation, tides, and ambient stratification but also influenced by the river discharge from the estuary head. For example, when the river discharge from the estuary head arrives, the strong seaward flow causes lateral river plume to spread more downstream. A series of numerical experiments are conducted to find the key factors on the lateral river plume dynamics. The results of this study are important to understand the pathways and fates of the lateral riverine materials into the estuary. Key Points: Lateral river plume spreads further downstream with the addition of river discharge from the estuary headTidal mixing and advection overwhelm tidal residual current on changing the lateral plume's structureInitial vertical stratification enhances the offshore dispersal of the lateral river plume [ABSTRACT FROM AUTHOR] |
| Databáze: |
GreenFILE |
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