气候变化领域集成服务门户(CCPortal): Residual Sediment Transport in Tidally Energetic Estuarine Channels With Lateral Bathymetric Variation

CCPortal

DOI	10.1029/2020JC016140
	Residual Sediment Transport in Tidally Energetic Estuarine Channels With Lateral Bathymetric Variation
	Zhou J.; Stacey M.T.
发表日期	2020
ISSN	21699275
卷号	125 期号:10
英文摘要	The residual sediment transport in tidally energetic estuarine channels is investigated by means of idealized cross-sectional modeling. The lateral bathymetric variation follows a Gaussian profile, assuming longitudinal uniformity. The total along-channel residual sediment flux is decomposed into contributions from an advective flux and a tidal pumping flux. Two important mechanisms are found to modify the tidal covariance between sediment concentration and current velocity, thereby contributing to the tidal pumping of sediment. First, longitudinal and lateral straining of salinity leads to tidal asymmetries in stratification and thus sediment resuspension. Second, lateral circulations directly redistribute suspended sediments within the cross section, which are then differentially transported by the along-channel tidal currents. A general relationship between the phasing of the lateral circulations and the resulting lateral-advection-driven tidal pumping is proposed. Reduced-physics experiments with lateral sediment advection turned off provide the first evidence that lateral-advection-driven tidal pumping plays a leading role in sediment transport for tidally energetic estuaries with nonnegligible lateral depth gradients. Additionally, a temporal decomposition breaks down the cross-sectionally averaged tidal pumping flux into individual contributions from different tidal phases (early tide, peak tide, and late tide), providing a new perspective on tidal asymmetry in sediment resuspension and settling. The direction and strength of tidal pumping (both stratification-driven and lateral-advection-driven) are shown to depend on lateral bathymetry, sediment grain size, and longitudinal buoyancy gradient forcing. ©2020. American Geophysical Union. All Rights Reserved.
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/186609
作者单位	Department of Civil and Environmental Engineering, University of California, Berkeley, CA, United States
推荐引用方式 GB/T 7714	Zhou J.,Stacey M.T.. Residual Sediment Transport in Tidally Energetic Estuarine Channels With Lateral Bathymetric Variation[J],2020,125(10).
APA	Zhou J.,&Stacey M.T..(2020).Residual Sediment Transport in Tidally Energetic Estuarine Channels With Lateral Bathymetric Variation.Journal of Geophysical Research: Oceans,125(10).
MLA	Zhou J.,et al."Residual Sediment Transport in Tidally Energetic Estuarine Channels With Lateral Bathymetric Variation".Journal of Geophysical Research: Oceans 125.10(2020).