气候变化领域集成服务门户(CCPortal): Wave Modulation of Flows on Open and Closed Reefs

CCPortal

DOI	10.1029/2020JC016645
	Wave Modulation of Flows on Open and Closed Reefs
	Lindhart M.; Rogers J.S.; Maticka S.A.; Woodson C.B.; Monismith S.G.
发表日期	2021
ISSN	21699275
卷号	126 期号:4
英文摘要	Using observations, numerical models, and theory, we explore a framework to classify reefs as open or closed based on their dynamics. While the concepts of open and closed reefs are used widely in studies of coral reef hydrodynamics and are generally based on geometry, there is no consensus on what qualifies as open and closed. With observations from Ofu, American Samoa, we show that the reef flat exhibits two different dynamical regimes depending on tidal and wave forcing. Flow over this reef flat resembles a classic one-dimensional barrier reef flow during low tide, where wave setup creates a cross-reef pressure gradient which forces flow on the flat. On high tide, however, flow on the flat is oblique to the crest, and at times directed offshore. We reproduce this behavior in an idealized numerical model of a fringing reef. We classify open reefs as a condition where an onshore, wave-generated pressure gradient is balanced by friction, and closed reefs as a condition where an onshore radiation stress gradient is opposed by an offshore pressure gradient. Results from the fringing reef model show that the system transitions between open and closed behavior over a tidal cycle. Results from an additional barrier reef numerical model exhibits almost exclusively open reef behavior, for which we derive a simple theoretical model. We argue that classifying reefs as open or closed based on their dynamics, rather than geometry, is a more meaningful approach to comparing reefs and predicting their dynamical response to wave and tidal forcing. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	Closed reef; coral reef; open reef; wave-driven 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/186368
作者单位	Bob and Norma Street Environmental Fluid Mechanics Laboratory, Department of Civil and Environmental Engineering, Stanford University, Stanford, CA, United States; COBIA Lab, University of Georgia, Athens, GA, United States
推荐引用方式 GB/T 7714	Lindhart M.,Rogers J.S.,Maticka S.A.,et al. Wave Modulation of Flows on Open and Closed Reefs[J],2021,126(4).
APA	Lindhart M.,Rogers J.S.,Maticka S.A.,Woodson C.B.,&Monismith S.G..(2021).Wave Modulation of Flows on Open and Closed Reefs.Journal of Geophysical Research: Oceans,126(4).
MLA	Lindhart M.,et al."Wave Modulation of Flows on Open and Closed Reefs".Journal of Geophysical Research: Oceans 126.4(2021).