气候变化领域集成服务门户(CCPortal): Exchange Flow and Material Transport Along the Salinity Gradient of a Long Estuary

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DOI	10.1029/2021JC017185
	Exchange Flow and Material Transport Along the Salinity Gradient of a Long Estuary
	Xiong J.; Shen J.; Qin Q.
发表日期	2021
ISSN	21699275
卷号	126 期号:5
英文摘要	Most estuaries are characterized by non-uniform axial topography with shallow shoals near the mouth. Previous studies have addressed the impacts of the axial topographic variations on mixing and estuarine circulations yet seldom on material transport and retention. This study investigates the longitudinal structure and mechanisms of exchange flow and material transport of Chesapeake Bay (CB), featuring a shallow sill in the lower bay, by applying total exchange flow (TEF) algorithm, tracer experiments, and partial residence time (PRT) using a validated 32-years numerical model simulation. A retention coefficient was adopted to quantify the material retention rate using two characteristic PRTs: with and without incorporating water parcels returning to a concerned region. It is found that shoaling from the Rappahannock Shoal to the mouth causes persistent downwelling, strong reflux, and the highest material retention rate in the middle of the bay. The gravitational circulation and the river outflow dominate the transport of salt and riverine dissolved materials (RDMs), whereas the contribution of the tidal oscillatory process is localized near the mouth. The dominance of river outflow over the gravitational circulation for transporting RDMs is confined within the upper bay, where PRTs exhibit distinct seasonality. PRTs show small seasonality in the middle to the lower bay controlled by the exchange flow. The present analysis combining TEF, efflux/reflux theory, and PRT is applicable to other coastal aquatic ecosystems to characterize the water exchange and renewal efficiency along the salinity gradient and understand the contributions of transport to biogeochemical processes. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	Chesapeake Bay; convergence/divergence; material retention coefficient; partial residence time; reflux/efflux; topography-induced downwelling/upwelling; total exchange flow
语种	英语
来源期刊	Journal of Geophysical Research: Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/186296
作者单位	Virginia Institute of Marine Science, William & Mary, Gloucester Point, VA, United States
推荐引用方式 GB/T 7714	Xiong J.,Shen J.,Qin Q.. Exchange Flow and Material Transport Along the Salinity Gradient of a Long Estuary[J],2021,126(5).
APA	Xiong J.,Shen J.,&Qin Q..(2021).Exchange Flow and Material Transport Along the Salinity Gradient of a Long Estuary.Journal of Geophysical Research: Oceans,126(5).
MLA	Xiong J.,et al."Exchange Flow and Material Transport Along the Salinity Gradient of a Long Estuary".Journal of Geophysical Research: Oceans 126.5(2021).