• Bishop, S. P., D. R. Watts, and K. A. Donohue, 2013: Divergent eddy heat fluxes in the Kuroshio Extension at 144°–148°E. Part I: Mean structure. J. Phys. Oceanogr., 43, 15331550, https://doi.org/10.1175/JPO-D-12-0221.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Boccaletti, G., R. Ferrari, and B. Fox-Kemper, 2007: Mixed layer instabilities and restratification. J. Phys. Oceanogr., 37, 22282250, https://doi.org/10.1175/JPO3101.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Brachet, S., P. Y. Le Traon, and C. Le Provost, 2004: Mesoscale variability from a high-resolution model and from altimeter data in the North Atlantic Ocean. J. Geophys. Res., 109, C12025, https://doi.org/10.1029/2004JC002360.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chang, Y.-L., and L.-Y. Oey, 2014: Instability of the North Pacific Subtropical Countercurrent. J. Phys. Oceanogr., 44, 818833, https://doi.org/10.1175/JPO-D-13-0162.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chelton, D. B., M. G. Schlax, and R. M. Samelson, 2011: Global observations of nonlinear mesoscale eddies. Prog. Oceanogr., 91, 167216, https://doi.org/10.1016/j.pocean.2011.01.002.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chen, X., B. Qiu, S. Chen, Y. Qi, and Y. Du, 2015: Seasonal eddy kinetic energy modulations along the North Equatorial Countercurrent in the western Pacific. J. Geophys. Res. Oceans, 120, 63516362, https://doi.org/10.1002/2015JC011054.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Cronin, M. F., and Coauthors, 2013: Formation and erosion of the seasonal thermocline in the Kuroshio Extension Recirculation Gyre. Deep-Sea Res. II, 85, 6274, https://doi.org/10.1016/j.dsr2.2012.07.018.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Cummings, J. A., 2005: Operational multivariate ocean data assimilation. Quart. J. Roy. Meteor. Soc., 131, 35833604, https://doi.org/10.1256/qj.05.105.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ducet, N., and P.-Y. Le Traon, 2001: A comparison of surface eddy kinetic energy and Reynolds stresses in the Gulf Stream and the Kuroshio Current Systems from merged TOPEX/Poseidon and ERS-1/2 altimetric data. J. Geophys. Res., 106, 16 60316 622, https://doi.org/10.1029/2000JC000205.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Duhaut, T. H. A., and D. N. Straub, 2006: Wind stress dependence on ocean surface velocity: Implications for mechanical energy input to ocean circulation. J. Phys. Oceanogr., 36, 202211, https://doi.org/10.1175/JPO2842.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Eden, C., and C. Böning, 2002: Sources of eddy kinetic energy in the Labrador Sea. J. Phys. Oceanogr., 32, 33463363, https://doi.org/10.1175/1520-0485(2002)032<3346:SOEKEI>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ferrari, R., and C. Wunsch, 2009: Ocean circulation kinetic energy: Reservoirs, sources, and sinks. Annu. Rev. Fluid Mech., 41, 253282, https://doi.org/10.1146/annurev.fluid.40.111406.102139.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Frankignoul, C., and P. Müller, 1979: Quasi-geostrophic response of an infinite β-plane ocean to stochastic forcing by the atmosphere. J. Phys. Oceanogr., 9, 104127, https://doi.org/10.1175/1520-0485(1979)009<0104:QGROAI>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Garnier, V., and R. Schopp, 1999: Wind influence on the mesoscale activity along the Gulf Stream and the North Atlantic currents. J. Geophys. Res., 104, 18 08718 110, https://doi.org/10.1029/1999JC900070.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hughes, C. W., and C. Wilson, 2008: Wind work on the geostrophic ocean circulation: An observational study of the effect of small scales in the wind stress. J. Geophys. Res., 113, C02016, https://doi.org/10.1029/2007JC004371.

    • Search Google Scholar
    • Export Citation
  • Itoh, S., and I. Yasuda, 2010: Characteristics of mesoscale eddies in the Kuroshio–Oyashio Extension region detected from the distribution of the sea surface height anomaly. J. Phys. Oceanogr., 40, 10181034, https://doi.org/10.1175/2009JPO4265.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jayne, S. R., and Coauthors, 2009: The Kuroshio Extension and its recirculation gyres. Deep-Sea Res. I, 56, 20882099, https://doi.org/10.1016/j.dsr.2009.08.006.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jia, F., L. Wu, and B. Qiu, 2011: Seasonal modulation of eddy kinetic energy and its formation mechanism in the southeast Indian Ocean. J. Phys. Oceanogr., 41, 657665, https://doi.org/10.1175/2010JPO4436.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jouanno, J., J. Sheinbaum, B. Barnier, J. M. Molines, and J. Candela, 2012: Seasonal and interannual modulation of the eddy kinetic energy in the Caribbean Sea. J. Phys. Oceanogr., 42, 20412055, https://doi.org/10.1175/JPO-D-12-048.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kang, D., E. N. Curchitser, and A. Rosati, 2016: Seasonal variability of the Gulf Stream kinetic energy. J. Phys. Oceanogr., 46, 11891207, https://doi.org/10.1175/JPO-D-15-0235.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kelly, K. A., R. J. Small, R. M. Samelson, B. Qiu, T. M. Joyce, Y.-O. Kwon, and M. F. Cronin, 2010: Western boundary currents and frontal air–sea interaction: Gulf Stream and Kuroshio Extension. J. Climate, 23, 56445667, https://doi.org/10.1175/2010JCLI3346.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lee, E., Y. Noh, B. Qiu, and S.-W. Yeh, 2015: Seasonal variation of the upper ocean responding to surface heating in the North Pacific. J. Geophys. Res. Oceans, 120, 56315647, https://doi.org/10.1002/2015JC010800.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Legg, S., and J. C. McWilliams, 2001: Convective modifications of a geostrophic eddy field. J. Phys. Oceanogr., 31, 874891, https://doi.org/10.1175/1520-0485(2001)031<0874:CMOAGE>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Liang, X. S., 2016: Canonical transfer and multiscale energetics for primitive and quasigeostrophic atmospheres. J. Atmos. Sci., 73, 44394468, https://doi.org/10.1175/JAS-D-16-0131.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Liang, X. S., and D. G. M. Anderson, 2007: Multiscale window transform. Multiscale Model. Simul., 6, 437467, https://doi.org/10.1137/06066895X.

  • Liang, X. S., and A. R. Robinson, 2007: Localized multi-scale energy and vorticity analysis: II. Finite-amplitude instability theory and validation. Dyn. Atmos. Oceans, 44, 5176, https://doi.org/10.1016/j.dynatmoce.2007.04.001.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mizuno, K., and W. B. White, 1983: Annual and interannual variability in the Kuroshio Current System. J. Phys. Oceanogr., 13, 18471867, https://doi.org/10.1175/1520-0485(1983)013<1847:AAIVIT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Müller, P., and C. Frankignoul, 1981: Direct atmospheric forcing of geostrophic eddies. J. Phys. Oceanogr., 11, 287308, https://doi.org/10.1175/1520-0485(1981)011<0287:DAFOGE>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Nakamura, H., A. Isobe, S. Minobe, H. Mitsudera, M. Nonaka, and T. Suga, 2015: “Hot spots” in the climate system—New developments in the extratropical ocean–atmosphere interaction research: A short review and an introduction. J. Oceanogr., 71, 463467, https://doi.org/10.1007/s10872-015-0321-5.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pedlosky, J., 1987: Geophysical Fluid Dynamics. 2nd ed. Springer-Verlag, 710 pp.

    • Crossref
    • Export Citation
  • Pierini, S., 2006: A Kuroshio Extension system model study: Decadal chaotic self-sustained oscillations. J. Phys. Oceanogr., 36, 16051625, https://doi.org/10.1175/JPO2931.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pujol, M.-I., and G. Larnicol, 2005: Mediterranean Sea eddy kinetic energy variability from 11 years of altimetric data. J. Mar. Syst., 58, 121142, https://doi.org/10.1016/j.jmarsys.2005.07.005.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Qiu, B., 1999: Seasonal eddy field modulation of the North Pacific Subtropical Countercurrent: TOPEX/Poseidon observations and theory. J. Phys. Oceanogr., 29, 24712486, https://doi.org/10.1175/1520-0485(1999)029<2471:SEFMOT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Qiu, B., and K. A. Kelly, 1993: Upper-ocean heat balance in the Kuroshio Extension region. J. Phys. Oceanogr., 23, 20272041, https://doi.org/10.1175/1520-0485(1993)023<2027:UOHBIT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Qiu, B., and S. Chen, 2005: Variability of the Kuroshio Extension jet, recirculation gyre, and mesoscale eddies on decadal time scales. J. Phys. Oceanogr., 35, 20902103, https://doi.org/10.1175/JPO2807.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Qiu, B., K. A. Kelly, and T. M. Joyce, 1991: Mean flow and variability in the Kuroshio Extension from Geosat altimetry data. J. Geophys. Res., 96, 18 49118 507, https://doi.org/10.1029/91JC01834.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Qiu, B., S. Chen, P. Klein, H. Sasaki, and Y. Sasai, 2014: Seasonal mesoscale and submesoscale eddy variability along the North Pacific Subtropical Countercurrent. J. Phys. Oceanogr., 44, 30793098, https://doi.org/10.1175/JPO-D-14-0071.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Renault, L., M. J. Molemaker, J. C. McWilliams, A. F. Shchepetkin, F. Lemarié, D. Chelton, S. Illig, and A. Hall, 2016: Modulation of wind work by oceanic current interaction with the atmosphere. J. Phys. Oceanogr., 46, 16851704, https://doi.org/10.1175/JPO-D-15-0232.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Renault, L., J. C. McWilliams, and S. Masson, 2017: Satellite observations of imprint of oceanic current on wind stress by air-sea coupling. Sci. Rep., 7, 17747, https://doi.org/10.1038/s41598-017-17939-1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Rieck, J. K., C. W. Böning, R. J. Greatbatch, and M. Scheinert, 2015: Seasonal variability of eddy kinetic energy in a global high-resolution ocean model. Geophys. Res. Lett., 42, 2015GL066152, https://doi.org/10.1002/2015GL066152.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sasaki, H., P. Klein, B. Qiu, and Y. Sasai, 2014: Impact of oceanic-scale interactions on the seasonal modulation of ocean dynamics by the atmosphere. Nat. Commun., 5, 5636, https://doi.org/10.1038/ncomms6636.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sasaki, H., P. Klein, Y. Sasai, and B. Qiu, 2017: Regionality and seasonality of submesoscale and mesoscale turbulence in the North Pacific Ocean. Ocean Dyn., 67, 11951216, https://doi.org/10.1007/s10236-017-1083-y.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Scharffenberg, M. G., and D. Stammer, 2010: Seasonal variations of the large-scale geostrophic flow field and eddy kinetic energy inferred from the TOPEX/Poseidon and Jason-1 tandem mission data. J. Geophys. Res., 115, C02008, https://doi.org/10.1029/2008JC005242.

    • Search Google Scholar
    • Export Citation
  • Scott, R. B., and Y. Xu, 2009: An update on the wind power input to the surface geostrophic flow of the World Ocean. Deep-Sea Res. I, 56, 295304, https://doi.org/10.1016/j.dsr.2008.09.010.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Stammer, D., and C. Wunsch, 1999: Temporal changes in eddy energy of the oceans. Deep-Sea Res. II, 46, 77108, https://doi.org/10.1016/S0967-0645(98)00106-4.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Stammer, D., C. Böning, and C. Dieterich, 2001: The role of variable wind forcing in generating eddy energy in the North Atlantic. Prog. Oceanogr., 48, 289311, https://doi.org/10.1016/S0079-6611(01)00008-8.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Tai, C.-K., and W. B. White, 1990: Eddy variability in the Kuroshio Extension as revealed by Geosat altimetry: Energy propagation away from the jet, Reynolds stress, and seasonal cycle. J. Phys. Oceanogr., 20, 17611777, https://doi.org/10.1175/1520-0485(1990)020<1761:EVITKE>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Uchida, T., R. Abernathey, and S. Smith, 2017: Seasonality of eddy kinetic energy in an eddy permitting global climate model. Ocean Modell., 118, 4158, https://doi.org/10.1016/j.ocemod.2017.08.006.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Vivier, F., K. A. Kelly, and L. A. Thompson, 2002: Heat budget in the Kuroshio Extension region: 1993–99. J. Phys. Oceanogr., 32, 34363454, https://doi.org/10.1175/1520-0485(2002)032<3436:HBITKE>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • von Appen, W.-J., U. Schauer, T. Hattermann, and A. Beszczynska-Möller, 2016: Seasonal cycle of mesoscale instability of the West Spitsbergen Current. J. Phys. Oceanogr., 46, 12311254, https://doi.org/10.1175/JPO-D-15-0184.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • von Storch, J.-S., H. Sasaki, and J. Marotzke, 2007: Wind-generated power input to the deep ocean: An estimate using a 1/10° general circulation model. J. Phys. Oceanogr., 37, 657672, https://doi.org/10.1175/JPO3001.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Waterman, S., N. G. Hogg, and S. R. Jayne, 2011: Eddy–mean flow interaction in the Kuroshio Extension region. J. Phys. Oceanogr., 41, 11821208, https://doi.org/10.1175/2010JPO4564.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • White, M. A., and K. J. Heywood, 1995: Seasonal and interannual changes in the North Atlantic subpolar gyre from Geosat and TOPEX/Poseidon altimetry. J. Geophys. Res., 100, 24 93124 941, https://doi.org/10.1029/95JC02123.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wunsch, C., 1998: The work done by the wind on the oceanic general circulation. J. Phys. Oceanogr., 28, 23322340, https://doi.org/10.1175/1520-0485(1998)028<2332:TWDBTW>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Xu, C., X. Zhai, and X.-D. Shang, 2016: Work done by atmospheric winds on mesoscale ocean eddies. Geophys. Res. Lett., 43, 12 17412 180, https://doi.org/10.1002/2016GL071275.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yang, H., L. Wu, H. Liu, and Y. Yu, 2013: Eddy energy sources and sinks in the South China Sea. J. Geophys. Res. Oceans, 118, 47164726, https://doi.org/10.1002/jgrc.20343.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yang, Y., and X. S. Liang, 2016: The instabilities and multiscale energetics underlying the mean–interannual–eddy interactions in the Kuroshio Extension region. J. Phys. Oceanogr., 46, 14771494, https://doi.org/10.1175/JPO-D-15-0226.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yang, Y., X. S. Liang, B. Qiu, and S. Chen, 2017: On the decadal variability of the eddy kinetic energy in the Kuroshio Extension. J. Phys. Oceanogr., 47, 11691187, https://doi.org/10.1175/JPO-D-16-0201.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yasuda, I., T. Tozuka, M. Noto, and S. Kouketsu, 2000: Heat balance and regime shifts of the mixed layer in the Kuroshio Extension. Prog. Oceanogr., 47, 257278, https://doi.org/10.1016/S0079-6611(00)00038-0.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Youngs, M. K., A. F. Thompson, A. Lazar, and K. J. Richards, 2017: ACC meanders, energy transfer, and mixed barotropic–baroclinic instability. J. Phys. Oceanogr., 47, 12911305, https://doi.org/10.1175/JPO-D-16-0160.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zhai, X., 2017: The annual cycle of surface eddy kinetic energy and its influence on eddy momentum fluxes as inferred from altimeter data. Satell. Oceanogr. Meteor., 2, 299, https://doi.org/10.18063/som.v2i2.299.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zhai, X., H. L. Johnson, D. P. Marshall, and C. Wunsch, 2012: On the wind power input to the ocean general circulation. J. Phys. Oceanogr., 42, 13571365, https://doi.org/10.1175/JPO-D-12-09.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zhan, P., A. C. Subramanian, F. Yao, A. R. Kartadikaria, D. Guo, and I. Hoteit, 2016: The eddy kinetic energy budget in the Red Sea. J. Geophys. Res. Oceans, 121, 47324747, https://doi.org/10.1002/2015JC011589.

    • Crossref
    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 64 64 23
PDF Downloads 61 61 23

On the Seasonal Eddy Variability in the Kuroshio Extension

View More View Less
  • 1 School of Marine Sciences, and Center for Ocean-Atmosphere Dynamical Studies, Nanjing University of Information Science and Technology, Nanjing, China
  • 2 School of Marine Sciences, and School of Atmospheric Sciences, and Center for Ocean-Atmosphere Dynamical Studies, Nanjing University of Information Science and Technology, Nanjing, China
© Get Permissions
Restricted access

Abstract

Using a recently developed tool, multiscale window transform (MWT), and the MWT-based canonical energy transfer theory, this study investigates the seasonal eddy variability in the Kuroshio Extension. Distinct seasonal cycles of eddy kinetic energy (EKE) are observed in the upstream and downstream regions of the Kuroshio Extension. In the upstream Kuroshio Extension, the EKE peaks in summer and reaches its minimum in winter over an annual cycle. By diagnosing the spatiotemporal structures of the canonical barotropic and baroclinic energy transfers, we found that internal processes due to mixed instabilities (i.e., both barotropic and baroclinic instabilities) are responsible for the seasonal eddy variability in this region. In the downstream Kuroshio Extension, the EKE exhibits a different annual cycle, peaking in spring and gradually decaying from summer to winter. Significant inverse barotropic energy transfer is found in this region throughout the year, leaving baroclinic instability the primary energy source for the regional seasonal eddy variability. Besides the internal redistribution, it is also evident that the external forcing may influence the Kuroshio Extension EKE seasonality—the EKE is found to be more damped by winds during winter than summer.

© 2018 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: X. San Liang, x.san.liang@gmail.com

Abstract

Using a recently developed tool, multiscale window transform (MWT), and the MWT-based canonical energy transfer theory, this study investigates the seasonal eddy variability in the Kuroshio Extension. Distinct seasonal cycles of eddy kinetic energy (EKE) are observed in the upstream and downstream regions of the Kuroshio Extension. In the upstream Kuroshio Extension, the EKE peaks in summer and reaches its minimum in winter over an annual cycle. By diagnosing the spatiotemporal structures of the canonical barotropic and baroclinic energy transfers, we found that internal processes due to mixed instabilities (i.e., both barotropic and baroclinic instabilities) are responsible for the seasonal eddy variability in this region. In the downstream Kuroshio Extension, the EKE exhibits a different annual cycle, peaking in spring and gradually decaying from summer to winter. Significant inverse barotropic energy transfer is found in this region throughout the year, leaving baroclinic instability the primary energy source for the regional seasonal eddy variability. Besides the internal redistribution, it is also evident that the external forcing may influence the Kuroshio Extension EKE seasonality—the EKE is found to be more damped by winds during winter than summer.

© 2018 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: X. San Liang, x.san.liang@gmail.com
Save