气候变化领域集成服务门户(CCPortal): Influence of Coriolis Force Upon Bottom Boundary Layers in a Large-Scale Gravity Current Experiment: Implications for Evolution of Sinuous Deep-Water Channel Systems

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DOI	10.1029/2019JC015284
	Influence of Coriolis Force Upon Bottom Boundary Layers in a Large-Scale Gravity Current Experiment: Implications for Evolution of Sinuous Deep-Water Channel Systems
	Davarpanah Jazi S.; Wells M.G.; Peakall J.; Dorrell R.M.; Thomas R.E.; Keevil G.M.; Darby S.E.; Sommeria J.; Viboud S.; Valran T.
发表日期	2020
ISSN	21699275
卷号	125 期号:3
英文摘要	Oceanic density currents in many deep-water channels are strongly influenced by the Coriolis force. The dynamics of the bottom boundary layer in large geostrophic flows and low Rossby number turbidity currents are very important for determining the erosion and deposition of sediment in channelized contourite currents and many large-scale turbidity currents. However, these bottom boundary layers are notoriously difficult to resolve with oceanic field measurements or in previous small-scale rotating laboratory experiments. We present results from a large, 13-m diameter, rotating laboratory platform that is able to achieve both stratified and highly turbulent flows in regimes where the rotation is sufficiently rapid that the Coriolis force can potentially dominate. By resolving the dynamics of the turbulent bottom boundary in straight and sinuous channel sections, we find that the Coriolis force can overcome centrifugal force to switch the direction of near-bed flows in channel bends. This occurs for positive Rossby numbers less than +0.8, defined as RoR = (Formula presented.) /Rf, where (Formula presented.) is the depth and time-averaged velocity, R is the radius of channel curvature, and f is the Coriolis parameter. Density and velocity fields decoupled in channel bends, with the densest fluid of the gravity current being deflected to the outer bend of the channel by the centrifugal force, while the location of velocity maximum shifted with the Coriolis force, leading to asymmetries between left- and right-turning bends. These observations of Coriolis effects on gravity currents are synthesized into a model of how sedimentary structures might evolve in sinuous turbidity current channels at various latitudes. © 2020. American Geophysical Union. All Rights Reserved.
英文关键词	centrifugal force; Coriolis force; Ekman boundary layers; gravity currents; laboratory experiments; sinuous submarine channels
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/186946
作者单位	Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto, ON, Canada; School of Earth & Environment, University of Leeds, Leeds, United Kingdom; Energy and Environment Institute, University of Hull, Hull, United Kingdom; School of Geography and Environmental Sciences, University of Southampton, Southampton, United Kingdom; Laboratoire des Écoulements Géophysiques et Industriels (LEGI), Grenoble, France
推荐引用方式 GB/T 7714	Davarpanah Jazi S.,Wells M.G.,Peakall J.,et al. Influence of Coriolis Force Upon Bottom Boundary Layers in a Large-Scale Gravity Current Experiment: Implications for Evolution of Sinuous Deep-Water Channel Systems[J],2020,125(3).
APA	Davarpanah Jazi S..,Wells M.G..,Peakall J..,Dorrell R.M..,Thomas R.E..,...&Valran T..(2020).Influence of Coriolis Force Upon Bottom Boundary Layers in a Large-Scale Gravity Current Experiment: Implications for Evolution of Sinuous Deep-Water Channel Systems.Journal of Geophysical Research: Oceans,125(3).
MLA	Davarpanah Jazi S.,et al."Influence of Coriolis Force Upon Bottom Boundary Layers in a Large-Scale Gravity Current Experiment: Implications for Evolution of Sinuous Deep-Water Channel Systems".Journal of Geophysical Research: Oceans 125.3(2020).