DOI: 10.1029/2017JF004425
Scopus记录号: 2-s2.0-85047663790
论文题名: Shortwave Sand Transport in the Shallow Surf Zone
作者: Brinkkemper J.A. ; Aagaard T. ; deBakker A.T.M. ; Ruessink B.G.
刊名: Journal of Geophysical Research: Earth Surface
ISSN: 21699003
出版年: 2018
卷: 123, 期: 5 起始页码: 1145
结束页码: 1159
语种: 英语
英文关键词: measurements
; sand transport
; surf zone
; wave asymmetry
Scopus关键词: flow modeling
; flow velocity
; morphodynamics
; ocean wave
; sediment transport
; shallow water
; surf zone
; turbulence
; Ameland
; Frisian Islands
; Netherlands
; West Frisian Islands
英文摘要: Empirical parameterizations of the shortwave sand transport that are used in practical engineering models lack the representation of certain processes to accurately predict morphodynamics in shallow water. Therefore, measurements of near-bed velocity and suspended sand concentration, collected during two field campaigns (at the Sand Engine and Ameland, the Netherlands) and one field-scale laboratory experiment (BARDEXII), were here analyzed to study the magnitude and direction of the shortwave sand flux in the shallow surf zone. Shortwave sand fluxes dominated the total sand flux during low-energetic accretive conditions, while the mean cross-shore current (undertow) dominated the total flux during high-energetic erosive conditions. Under low-energetic conditions, the onshore-directed shortwave sand flux scales with the root-mean-square orbital velocity urms and velocity asymmetry Au but not with the velocity skewness. Under more energetic conditions the shortwave flux reduces with an increase in the cross-shore mean current (Formula presented.) and can even become offshore directed. For all data combined, the contribution of the shortwave flux to the total flux scales with (Formula presented.), with a high contribution of the shortwave flux (∼70%) when this ratio is high (∼ 10) and low contributions (∼0%) when this ratio is low (∼1). We argue that the velocity asymmetry is a good proxy for the net effect of several transport mechanisms in the shallow surf zone, including breaking-induced turbulence. These field and laboratory measurements under irregular waves thus support the hypothesis that the inclusion of velocity asymmetry in transport formulations would improve the performance of morphodynamic models in shallow water. ©2018. The Authors. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/114032
Appears in Collections: 气候减缓与适应
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作者单位: Department of Physical Geography, Faculty of Geosciences, Utrecht University, Utrecht, Netherlands; Now at Waterproof Marine Consultancy and Services, Lelystad, Netherlands; Institute of Geoscience and Natural Resources, University of Copenhagen, Copenhagen K, Denmark; UMR 7266 LIENSs, CNRS Université de la Rochelle, La Rochelle, France
Recommended Citation:
Brinkkemper J.A.,Aagaard T.,deBakker A.T.M.,et al. Shortwave Sand Transport in the Shallow Surf Zone[J]. Journal of Geophysical Research: Earth Surface,2018-01-01,123(5)