Cite this paper:
YANG Bing, HOU Yijun, HU Po. Observed near-inertial waves in the wake of Typhoon Hagupit in the northern South China Sea[J]. Journal of Oceanology and Limnology, 2015, 33(5): 1265-1278

Observed near-inertial waves in the wake of Typhoon Hagupit in the northern South China Sea

YANG Bing1,2,3, HOU Yijun1,2, HU Po1,2
1 Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China;
2 Key Laboratory of Chinese Academy of Sciences for Ocean Circulation and Waves, Institute of Oceanology, Qingdao 266071, China;
3 University of Chinese Academy of Sciences, Beijing 100049, China
Abstract:
Energetic near-inertial internal waves (NIWs) were observed on the continental slope of the northern South China Sea in September 2008.Characteristics of the observed near-inertial waves were examined based on current data recorded by a moored acoustic Doppler current profiler.Results of a simple slab model indicated that the NIWs were generated by the surface winds of Typhoon Hagupit.Following Hagupit's passage, the wave field was dominated by baroclinic NIWs.The near-inertial currents were surface-intensified with a maximum of 0.52 m/s but still reached 0.1 m/s at the depth of 210 m.Moreover, the near-inertial currents were clockwise-polarized and slightly elliptical.A depth-leading phase of the nearinertial currents was evident, which indicated downward energy propagation.However, the rotary vertical wavenumber spectra suggested that upward energy propagation also existed, which was consistent previous theoretical study.The frequency of the NIWs, modified by the positive background vorticity, was 0.714 2 cycles per day, which was 0.02 f0 higher than the local inertial frequency (f0).The near-inertial kinetic energy evolved exponentially and had an e-folding timescale of about 3 days.The vertical phase and group velocity were estimated to be 10 and 2.1 m/h, respectively, corresponding to a vertical wavelength of 340 m.The NIWs were dominated by the second mode with a variance contribution of >50%, followed by the third mode, while the first mode was insignificant.
Key words:    near-inertial internal waves|South China Sea|Typhoon Hagupit   
Received: 2014-09-28   Revised: 2015-01-03
Tools
PDF ( KB) Free
Print this page
Add to favorites
Email this article to others
Authors
Articles by YANG Bing
Articles by HOU Yijun
Articles by HU Po
References:
Alford M H, Lien R C, Simmons H et al.2010.Speed and evolution of nonlinear internal waves transiting the South China Sea.J.Phys.Oceanogr., 40 (6): 1 338-1 355.
Alford M H.2001.Internal swell generation: the spatial distribution of energy flux from the wind to mixed layer near-inertial motions.J.Phys.Oceanogr., 31 (8): 2 359-2 368.
Amante C, Eakins B W.2009.ETOPO1 1 arc-minute global relief model: procedures, data sources and analysis.National Geophysical Data Center, NOAA, Boulder Colorado.http://dx.doi.org/10.7289/V5C8276M.
Brooks D A.1983.The wake of hurricane Allen in the western gulf of Mexico.J.Phys.Oceanogr., 13 (1): 117-129.
Byun S S, Park J J, Chang K I, Schmitt R W.2010.Observation of near-inertial wave reflections within the thermostad layer of an anticyclonic mesoscale eddy.Geophys.Res.Lett., 37: L041606.
Chen G X, Xue H J, Wang D X, Xie Q.2013.Observed nearinertial kinetic energy in the northwestern South China Sea.J.Geophys.Res., 118 (10): 4 965-4 977.
Chu P C, Veneziano J M, Fan C W, Carron M J, Liu W.2000.Response of the South China Sea to tropical cyclone Ernie 1996.J.Geophys.Res., 105 (C6): 13 991-14 009.
Cuypers Y, Vaillant X L, Bouruet-Aubertot P, Vialard J,McPhaden M J.2013.Tropical storm induced nearinertial internal waves during the Cirene experiment: energy fluxes and impact on vertical mixing.J.Geophys.Res., 118 (1): 358-380.
D'Asaro E A.1985.The energy flux from the wind tonearinertial motions in the surface mixed layer.J.Phys.Oceanogr., 15 (8): 1 043-1 059.
D'Asaro E A.1995.A collection of papers on the ocean storms experiment.J.Phys.Oceanogr., 25 (11): 2 817-2 818.
Fofonoff N P, Millard R C Jr.1983.Algorithms for computation of fundamental properties of seawater.In: Unesco Technical Papers in Marine Science.Unesco, Paris.53p.
Fu L L.1981.Observations and models of inertial waves in the deep ocean.Rev.Geophys., 19 (1): 141-170.
Garrett C.2001.What is the "near-inertial" band and why is it different from the rest of the internal wave spectrum? J.Phys.Oceanogr., 31 (4): 962-971.
Geisler J E.1970.Linear theory of the response of a two layer ocean to a moving hurricane.Geophys.Fluid Dyn., 1 (1-2): 249-272.
Gill A E.1982.Atmosphere-Ocean Dynamics.Academic Press, New York.346p.
Gill A E.1984.On the behavior of internal waves in the wakes of storms.J.Phys.Oceanogr., 14 (7): 1 129-1 151.
Gonella J.1972.A rotary-component method for analysing meteorological and oceanographic vector time series.Deep Sea Res.Oceanogr.Abstr, 19 (12): 833-846.
Guo C, Chen X.2014.A review of internal solitary wave dynamics in the northern South China Sea.Prog.Oceanogr., 121: 7-23.
Kunze E.1985.Near-inertial wave propagation in geostrophic shear.J.Phys.Oceanogr., 15 (5): 544-565.
Leaman K D, Sanford T B.1975.Vertical energy propagation of inertial waves: a vector spectral analysis of velocity profiles.J.Geophys.Res., 80 (15): 1 975-1 978.
Lee D K, Niiler P P.1998.The inertial chimney: the nearinertial energy drainage from the ocean surface to the deep layer.J.Geophys.Res., 103 (C4): 7 579-7 591.
Lee I H, Wang Y H, Yang Y, Wang D P.2012.Temporal variability of internal tides in the northeast South China Sea.J.Geophys.Res., 117 (C2): C02013.
Liu J L, Cai S Q, Wang S G.2011.Observations of strong nearbottom current after the passage of Typhoon Pabuk in the South China Sea.J.Mar.Res., 87 (1): 102-108.
Liu Q Y, Kaneko A, Su J L.2008.Recent progress in studies of the South China Sea circulation.J.Oceanogr., 64 (5): 753-762.
Ma B B, Lien R C, Ko D S.2013.The variability of internal tides in the Northern South China Sea.J.Oceanogr., 69 (5): 619-630.
Mackinnon J A, Gregg M C.2005.Near-inertial waves on the New England shelf: the role of evolving stratification, turbulent dissipation, and bottom drag.J.Phys.Oceanogr., 35 (12): 2 408-2 424.
Moehlis J, Smith S G L.2001.Radiation of mixed layer nearinertial oscillations into the ocean interior.J.Phys.Oceanogr., 31 (6): 1 550-1 560.
Munk W, Wunsch C.1998.Abyssal recipes II: energetics of tidal and wind mixing.Deep Sea Res., 45 (12): 1 977-2 010.
Oey L Y, Ezer T, Wang D P, Fan S J, Yin X Q.2006.Loop Current warming by Hurricane Wilma.Geophys.Res.Lett., 33 (8): L08613.
Park J J, Kim K, Schmitt R W.2009.Global distribution of the decay timescale of mixed layer inertial motions observed by satellite tracked drifters.J.Geophys.Res., 114 (C11):C11010.
Plueddemann A J, Farrar J T.2006.Observations and models of the energy flux from the wind to mixed-layer inertial currents.Deep Sea Res., 53 (1-2): 5-30.
Pollard R T, Millard R C.1970.Comparison between observed and simulated wind-generated inertial oscillations.Deep Sea Res., 17 (4): 813-821.
Pollard R T.1980.Properties of near-surface inertial oscillations.J.Phys.Oceanogr., 10 (3): 385-398.
Price J F.1983.Internal wave wake of a moving storm.Part I.Scales, energy budget and observations.J.Phys.Oceanogr., 13 (6): 949-965.
Qi H B, De Szoeke R A, Paulson C A, Eriksen C C.1995.The structure of near-inertial waves during ocean storms.J.Phys.Oceanogr., 25 (11): 2 853-2 871.
Rossby C G.1937.On the mutual adjustment of pressure and velocity distributions in certain simple current systems.J.Mar.Res., 1 (3): 239-263.
Shay L K, Chang S W, Elsberry R L.1990.Free surface effects on the near-inertial ocean current response to a hurricane.J.Phys.Oceanogr., 20 (9): 1 405-1 424.
Shay L K, Elsberry R L.1987.Near-inertial ocean current response to Hurricane Frederic.J.Phys.Oceanogr., 17 (8): 1 249-1 269.
Silverthorne K E, Toole J M.2009.Seasonal kinetic energy variability of near-inertial motions.J.Phys.Oceanogr., 39 (4): 1 035-1 049.
Sun L, Zheng Q A, Tang T Y et al.2012.Upper ocean nearinertial response to 1998 Typhoon Faith in the South China Sea.Acta Oceanol.Sin., 31 (2): 25-32.
Sun L, Zheng Q A, Wang D X et al.2011a.A case study of near-inertial oscillation in the South China Sea using mooring observations and satellite altimeter data.J.Oceanogr., 67 (6): 677-687.
Sun Z Y, Hu J Y, Zheng Q A et al.2011b.Strong near-inertial oscillations in geostrophic shear in the northern South China Sea.J.Oceanogr., 67 (4): 377-384.
Wang G H, Su J L, Ding Y H et al.2007.Tropical cyclone genesis over the South China Sea.J.Mar.Syst., 68 (3-4): 318-326.
Wang G, Qiao F L, Hou Y J et al.2008.Response of internal waves to 2005 Typhoon Damrey over the northwestern shelf of South China Sea.J.Ocean Univ.Chin., 7 (3): 251-257.
Welch P.1967.The use of fast Fourier transform for the estimation of power spectra: a method based on time averaging over short, modified periodograms.IEEE Trans.Audio Electroacoust., 15 (2): 70-73.
Xu Z H, Yin B S, Hou Y J et al.2013.Variability of internal tides and near-inertial waves on the continental slope of the northwestern South China Sea.J.Geophys.Res., 118 (1): 197-211.
Yang B, Hou Y J.2014.Near-inertial waves in the wake of 2011 Typhoon Nesat in the northern South China Sea.Acta Oceanol.Sin., 33 (11): 102-111.
Zervakis V, Levine M.1995.Near-inertial energy propagation from the mixed layer: theoretical considerations.J.Phys.Oceanogr., 25 (11): 2 872-2 889.
Zheng Q A, Lai R J, Huang N E et al.2006.Observation of ocean current response to 1998 Hurricane Georges in the Gulf of Mexico.Acta Oceanol.Sin., 25 (1): 1-14.
Copyright © Haiyang Xuebao