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摘要: 通过使用西沙海域锚定潜标的测流数据,分析了距浣熊台风路径100 km处海流受浣熊台风影响前后的动能谱、旋转谱和流剪切谱,从而阐明近惯性波,以及近惯性波与全日内潮波的相互作用机制.台风浣熊之后所引起的近惯性波主要在上250 m较强,其能量是普通风场所引起的40倍.近惯性波的能量向下传播至450 m左右,与此同时,强的近惯性流的剪切驱动着惯性波与全日内潮波之间的相互作用,从而产生强的近惯性波与全日内波的耦合波(f+D1).此三波耦合机制为Davies的波波相互作用理论提供了观测依据,同时,近惯性内波与全日内潮波之间的非线性相互作用,揭示了南海近惯性波能量耗散的一种机制.Abstract: To study the behaviors of near-inertial waves and the physical mechanism of nonlinear interaction between near-inertial waves and diurnal internal tidal waves by employing the data collected by moored ADCP in the northwestern South China Sea, the authors analyzed kinetic energy spectra,rotary spectra and the spectra of horizontal component difference in vertical direction. The authors investigated the upper-ocean responses after Typhoon Neoguri in the South China Sea (SCS) in April, 2008, and found that the intense energy of near-inertial waves after Typhoon Neoguri was dominant in the upper 250 m,which is about 40 times of the average value of near-inertial waves induced by winds (excluding Typhoon Neoguri).The energy of near-inertial waves can propagate downward to ~450 m. Furthermore, the intense horizontal flow difference drives interaction between near-inertial waves and diurnal internal tidal waves, and (f+D1) were oberserved. The wave-wave couple mechanism provides observational evidence for theoretical results.The process of nonlinear interacting reveals a significant energy dissipation mechanism in SCS.
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Key words:
- Near-inertial motions /
- Internal tides /
- Typhoon Neoguri /
- Xisha area in the SCS
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[1] Webster F. Observations of inertial-period motions in the deep sea. Reviews of Geophysics, 1968, 6(4): 473-490. doi: 10.1029/RG006i004p00473.
[2] Ekman V W. On the influence of the Earth's rotation on ocean-currents. Ark. Mat. Astron. Fys., 1905, 2(11): 1-52.
[3] Brooks D A. The wake of hurricane Allen in the western Gulf of Mexico. J. Phys. Oceanogr., 1983, 13(1): 117-129.
[4] Barron C N Jr, Vastano A C. Satellite observations of surface circulation in the northwestern Gulf of Mexico during March and April 1989. Cont. Shelf Res., 1994, 14(16): 607-627.
[5] Gill A E. Atmosphere-Ocean Dynamics. San Diego: Academic Press, 1982: 662.
[6] Munk W, Phillips N. Coherence and band structure of inertial motion in the sea. Rev. Geophys., 1968, 6(4): 447-472.
[7] Kroll J. The propagation of wind-generated inertial oscillations from the surface into the deep ocean. J. Mar. Res., 1975, 33: 15-51.
[8] Mihaly S F, Thomson R E, Rabinovich A B. Evidence for nonlinear interaction between internal waves of inertial and semidiurnal frequency. Geophys. Res. Lett., 1998, 25(8): 1205-1208.
[9] van Haren H, Maas L, Zimmerman J T F, et al. Strong inertial currents and marginal internal wave stability in the central North Sea. Geophys. Res. Lett., 1999, 26(19): 2993-2996.
[10] van Haren H, Maas L, Van Aken H. On the nature of internal wave spectra near a continental slope. Geophys. Res. Lett., 2002, 9(12): 1615, doi: 10.1029/2001GL014341.
[11] Müller P, Briscoe M. Diapycnal mixing and internal waves. // Müller P, Henderson D eds. Dynamics of Oceanic Internal Gravity Waves, II. Proceedings "Aha Huliko" a Hawaiian Winter Workshop, Honolulu: University of Hawaii at Manoa, 1999: 289-294.
[12] Alford M H. Observations of parametric subharmonic instability of the diurnal internal tide in the South China Sea. Geophys. Res. Lett., 2008, 35(15), doi: 10.1029/2008GL034720.
[13] Xie X H, Shang X D, Chen G Y, et al. Variations of diurnal and inertial spectral peaks near the bi-diurnal critical latitude. Geophys. Res. Lett., 2009, 36(2), doi: 10.1029/2008GL036383.
[14] Hibiya T, Nagasawa M. Latitudinal dependence of diapycnal diffusivity in the thermocline estimated using a finescale parameterization. Geophys. Res. Lett., 2004, 31(1), doi 10.1029/2003GL017998.
[15] van Haren H. Tidal and near-inertial peak variations around the diurnal critical latitude. Geophys. Res. Lett., 2005, 32(23), doi: 10.1029/2005GL024160.
[16] Kunze E, Firing E, Hummon J, et al. Global abyssal mixing inferred from lowered ADCP shear and CTD strain profiles. J. Phys. Oceanogr., 2006, 36(8): 1553-1576.
[17] Alford M H, MacKinnon J A, Zhao Z X, et al. Internal waves across the Pacific. Geophys. Res. Lett., 2007, 34(24), doi: 10.1029/2007GL031566.
[18] Jiang X P, Zhong Z, Jiang J. Upper ocean response of the South China Sea to typhoon Krovanh (2003). Dynamics of Atmospheres and Oceans, 2003, 47(1-3): 165-175.
[19] Gonella J. A rotary-component method for analysing meteorological and oceanographic vector time series. Deep-Sea Research and Oceanographic Abstracts, 1972, 19(12): 833-846.
[20] van Haren H, Millot C. Rectilinear and circular inertial motions in the Western Mediterranean Sea. Deep-Sea Research I: Ceanographic Research Papers, 2004, 51(11):1441-1455.
[21] van Haren H. Inertial and tidal shear variability above Reykjanes Ridge. Deep-Sea Research I: Ceanographic Research Papers, 2007, 54(6): 856-870.
[22] Davies A M, Xing J X. On the interaction between internal tides and wind-induced near-inertial currents at the shelf edge. J. Geophys. Res., 2003, 108(C3): 3099, doi: 10.1029/2002JC001375.
[23] Müller P, Holloway G, Henyey F, et al. Nonlinear interactions among internal gravity waves. Rev. Geophys., 1986, 24(3): 493-536.
[24] Gregg M C. Scaling turbulent dissipation in the thermocline. J. Geophys. Res., 1989, 94(C7): 9686-9698.
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