气候变化领域集成服务门户(CCPortal): Impact of Background Geostrophic Currents With Vorticity on Resonant Triad Interaction Over Mid-Ocean Ridges

CCPortal

DOI	10.1029/2021JC017227
	Impact of Background Geostrophic Currents With Vorticity on Resonant Triad Interaction Over Mid-Ocean Ridges
	Wang S.; Cao A.; Liang X.; Chen X.; Meng J.
发表日期	2021
ISSN	21699275
卷号	126 期号:4
英文摘要	Turbulent mixing driven by internal tides (ITs) in the ocean is essential for the maintenance of large-scale circulation. The resonant triad interaction (RTI) is an important mechanism by which ITs are dissipated. Based on a series of numerical simulations, we show that background geostrophic currents (BGCs) with nonzero vertical relative vorticity significantly impact the RTI by changing the effective Coriolis frequency. BGCs with negative vorticity (Northern Hemisphere) broaden the frequency range of internal waves so as to engender subharmonic waves at frequencies lower than the local Coriolis frequency near the topography. In addition, subharmonic waves at frequencies that are approximately half the tidal frequency are generated along the IT beams in the presence of BGCs with strong negative vorticity. Those subharmonic waves have larger vertical wavenumbers and hence smaller scales. In contrast, BGCs with positive vorticity (Northern Hemisphere) narrow the frequency range of internal waves and lead to the generation of energetic subharmonic beams. Intense RTI occurs when the effective Coriolis frequency is basically equal to half the tidal frequency, with powerful subharmonic waves detected at half the tidal frequency. Furthermore, in the presence of BGCs with vorticity, energy dissipation is significantly enhanced. Therefore, the development of parameterization of IT-driven mixing should consider the important role of BGCs in modulating RTI. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	background geostrophic current; internal tide; numerical simulation; relative vorticity; resonant triad interaction
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/186357
作者单位	Key Laboratory of Physical Oceanography, Ocean University of China, Qingdao and Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, China; Ocean College, Zhejiang University, Zhoushan, China; Laboratory for Regional Oceanography and Numerical Modeling, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, China; School of Marine Science and Policy, University of Delaware, Lewes, DE, United States; College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao, Shandong, China
推荐引用方式 GB/T 7714	Wang S.,Cao A.,Liang X.,et al. Impact of Background Geostrophic Currents With Vorticity on Resonant Triad Interaction Over Mid-Ocean Ridges[J],2021,126(4).
APA	Wang S.,Cao A.,Liang X.,Chen X.,&Meng J..(2021).Impact of Background Geostrophic Currents With Vorticity on Resonant Triad Interaction Over Mid-Ocean Ridges.Journal of Geophysical Research: Oceans,126(4).
MLA	Wang S.,et al."Impact of Background Geostrophic Currents With Vorticity on Resonant Triad Interaction Over Mid-Ocean Ridges".Journal of Geophysical Research: Oceans 126.4(2021).