气候变化领域集成服务门户(CCPortal): Near-Inertial Wave Propagation in the Wake of Super Typhoon Mangkhut: Measurements From a Profiling Float Array

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DOI	10.1029/2020JC016749
	Near-Inertial Wave Propagation in the Wake of Super Typhoon Mangkhut: Measurements From a Profiling Float Array
	Johnston T.M.S.; Wang S.; Lee C.-Y.; Moum J.N.; Rudnick D.L.; Sobel A.
发表日期	2021
ISSN	21699275
卷号	126 期号:2
英文摘要	Near-inertial internal waves (NIWs) are generated by inertially-rotating winds under tropical cyclones (TC). Since NIWs are mostly horizontal, their vertical propagation out of the mixed layer is slow. However, mesoscale vorticity and shear increase vertical group speed by increasing near-inertial frequency and horizontal wavenumber. To assess NIW propagation, a profiling float array under Super Typhoon Mangkhut in September 2018 made broad and persistent measurements in space and time of density in the upper 200 m and depth-mean velocity. The TC wake was a region of positive vorticity on its southern side, displayed elevated shear, and thereby enhanced downward propagation of NIWs. The vertical energy flux is estimated as 0.04–0.11 W m−2, which is about 1%–4% (3%–8%) of the mean total (near-inertial) wind work of 3.0 (1.3) W m−2 calculated from a high-resolution TC model. Considerable uncertainties arise in the (a) estimated group speed based on wavelength, shear, and frequency and (b) energy density based on depth-varying density and the NIW polarization relations, which are sensitive to frequency. Following the TC's passage, NIWs propagated southward and horizontal wavelengths decreased from 1,000 to 500 km, as time progressed. Also, we identify an interfacial wave at the mixed layer base, which displaces isopycnals vertically. The following process is suggested. As the North Equatorial Current flows over these displacements, which act as topographic obstacles, secondary NIWs propagate up-/downward into the mixed layer/thermocline. These waves are 180° out of phase in the mixed layer and thermocline, which can enhance shear at the mixed layer base. © 2020. American Geophysical Union. All Rights Reserved.
英文关键词	internal waves; profiling floats; tropical cyclone; wake
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/186467
作者单位	Scripps Institution of Oceanography, University of California, San Diego, CA, United States; Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY, United States; Lamont Doherty Earth Observatory, Columbia University, New York, NY, United States; College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, United States
推荐引用方式 GB/T 7714	Johnston T.M.S.,Wang S.,Lee C.-Y.,et al. Near-Inertial Wave Propagation in the Wake of Super Typhoon Mangkhut: Measurements From a Profiling Float Array[J],2021,126(2).
APA	Johnston T.M.S.,Wang S.,Lee C.-Y.,Moum J.N.,Rudnick D.L.,&Sobel A..(2021).Near-Inertial Wave Propagation in the Wake of Super Typhoon Mangkhut: Measurements From a Profiling Float Array.Journal of Geophysical Research: Oceans,126(2).
MLA	Johnston T.M.S.,et al."Near-Inertial Wave Propagation in the Wake of Super Typhoon Mangkhut: Measurements From a Profiling Float Array".Journal of Geophysical Research: Oceans 126.2(2021).