The Kuroshio Extension and its recirculation gyre form an interconnected dynamic system. The system is located at a crossroads where the meso-scale and large-scale oceanic variability are highest, and where the ocean-atmosphere interaction is most active in the Pacific Ocean outside of the tropics. Following a brief review of the mean flow and meso-scale eddy variability, this study describes in detail the large-scale structural change (an oscillation between an elongated and a contracted state) observed in the Kuroshio Extension system. Causes for this structural change are explored next, and it is argued that the basin-wide external wind forcing and the nonlinear dynamics associated with the inertial recirculation gyre are both important factors. Data analysis results are reviewed and presented, emphasizing that the surface Kuroshio Extension is not simply a well-mixed layer passively responding to heat flux anomalies imposed by the atmosphere. It is argued that large-scale changes in the Kuroshio Extension system influence the surface ocean heat balance and generate wintertime sea surface temperature (SST) anomalies through both horizontal geostrophic heat advection and re-emergence to the surface mixed layer of sequestered mode water temperature anomalies.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
Adamec, D. (1998): Modulation of the seasonal signal of the Kuroshio Extension during 1994 from satellite data. J. Geophys. Res., 103, 10,209–10,222.
Akitomo, K., M. Ooi, T. Awaji and K. Kutsuwada (1996): Interannual variability of the Kuroshio transport in response to the wind stress field over the North Pacific: Its relation to the path variation south of Japan. J. Geophys. Res., 101, 14,057–14,071.
Alexander, M. A. and C. Deser (1995): A mechanism for the recurrence of wintertime midlatitude SST anomalies. J. Climate, 25, 122–137.
Aoki, S., S. Imawaki and K. Ichikawa (1995): Baroclinic disturbances propagating westward in the Kuroshio Extension region as seen by a satellite altimeter and radiometers. J. Geophys. Res., 100, 839–855.
Berloff, P. S. and J. C. McWilliams (1999): Large-scale, low-frequency variability in wind-driven ocean gyres. J. Phys. Oceanogr., 29, 1925–1949.
Bernstein, R. L. and W. B. White (1981): Stationary and travelling mesoscale perturbations in the Kuroshio Extension current. J. Phys. Oceanogr., 11, 672–704.
Bingham, F. M., T. Suga and K. Hanawa (1992): Comparison of upper thermal conditions in the western North Pacific between two pentads: 1938–42 and 1978–82. J. Oceanogr., 48, 405–425.
Cayan, D. R. (1992): Latent and sensible heat flux anomalies over the Northern Oceans: Driving the sea surface temperature. J. Phys. Oceanogr., 22, 859–881.
Cessi, P., R. V. Condie and W. Young (1990): Dissipative dynamics of western boundary currents. J. Mar. Res., 48, 677–700.
Da Silva, A. M., C. C. Young and S. Levitus (1994): Atlas of Surface Marine Data 1994, Vol. 1: Algorithms and Procedures. NOAA Atlas NESDIS 6, U.S. Dept. of Commer., Washington, D.C., 83 pp.
Davis, R. E. (1976): Predictability of sea surface temperature and sea level pressure anomalies over the North Pacific Ocean. J. Phys. Oceanogr., 6, 249–266.
Deser, C. and M. L. Blackmon (1995): On the relationship between tropical and North Pacific sea surface variations. J. Climate, 8, 1677–1680.
Deser, C., M. A. Alexander and M. S. Timlin (1996): Upper-ocean thermal variations in the North Pacific during 1970–1991. J. Climate, 8, 1840–1855.
Deser, C., M. A. Alexander and M. S. Timlin (1999): Evidence for a wind-driven intensification of the Kuroshio Current Extension from the 1970s to the 1980s. J. Climate, 12, 1697–1706.
Ebuchi, N. and K. Hanawa (2000): Mesoscale eddies observed by TOLEX-ADCP and TOPEX/POSEIDON altimeter in the Kuroshio recirculation region south of Japan. J. Oceanogr., 56, 43–57.
Frankignoul, C. (1985): Sea surface temperature anomalies, planetary waves, and air-sea feedback in the middle latitudes. Rev. Geophys., 23, 357–390.
Gu, D. and S. G. H. Philander (1997): Interdecadal climate fluctuations that depend on exchanges between the tropics and extratropics. Science, 275, 805–807.
Hall, M. M. (1989): Velocity and transport structure of the Kuroshio Extension at 35°N, 152°E. J. Geophys. Res., 94, 14,445–14,459.
Hall, M. M. (1991): Energetics of the Kuroshio Extension at 35°N, 152°E. J. Phys. Oceanogr., 21, 958–975.
Hanawa, K. (1987): Interannual variations of the winter-time outcrop area of subtropical mode water in the western North Pacific Ocean. Atmos-Ocean, 25, 358–374.
Hanawa, K. and J. Kamada (2001): Variability of core layer temperature (CLT) of the North Pacific Subtropical Mode Water. Geophys. Res. Lett., 28 (in press).
Hanawa, K. and L. D. Talley (2001): Mode waters. p. 373–386. In Ocean Circulation and Climate, Chap. 5.4, ed. by G. Siedler, J. Church and J. Gould, Academic Press.
Hautala, S. L. and D. H. Roemmich (1998): Subtropical mode water in the Northeast Pacific Basin. J. Geophys. Res., 103, 13,055–13,066.
Hautala, S. L., D. H. Roemmich and W. J. Schmitz, Jr. (1994): Is the North Pacific in Sverdrup balance along 24°N? J. Geophys. Res., 99, 16,041–16,052.
Hellerman, S. and M. Rosenstein (1983): Normal monthly wind stress over the world ocean with error estimates. J. Phys. Oceanogr., 13, 1093–1104.
Huang, R. X. and B. Qiu (1994): Three-dimensional structure of the wind-driven circulation in the subtropical North Pacific. J. Phys. Oceanogr., 24, 1608–1622.
Hurlburt, H. E., A. J. Wallcraft, W. J. Schmitz, P. J. Hogan and E. J. Metzger (1996): Dynamics of the Kuroshio/Oyashio current system using eddy-resolving models of the North Pacific Ocean. J. Geophys. Res., 101, 941–976.
Ichikawa, K. and S. Imawaki (1994): Life history of a cyclonic ring detached from the Kuroshio Extension as seen by the Geosat altimeter. J. Geophys. Res., 99, 15,953–15,966.
Imawaki, S., H. Uchida, H. Ichikawa, M. Fukasawa, S. Umatani and the ASUKA Group (2001): Satellite altimeter monitoring the Kuroshio transport south of Japan. Geophys. Res. Lett., 28, 17–20.
Iwasaka, N. and J. M. Wallace (1995): Large scale air sea interaction in the Northern Hemisphere from a view point of variations of surface heat flux by SVD analysis. J. Meteoro. Soc. Japan, 73, 781–794.
Jacobs, G. A., H. E. Hurlburt, J. C. Kindle, E. J. Metzger, J. L. Mitchell, W. J. Teague and A. J. Wallcraft (1994): Decade-scale trans-Pacific propagation and warming effects of an El Niño warming anomaly. Nature, 370, 360–363.
Jiang, S., F. F. Jin and M. Ghil (1995): Multiple equilibria, periodic, and aperiodic solutions in a wind-driven, double-gyre, shallow-water model. J. Phys. Oceanogr., 25, 764–786.
Joyce, T. M. (1987): Hydrographic sections across the Kuroshio extension at 165°E and 175°W. Deep-Sea Res., 34, 1331–1352.
Joyce, T. M. and W. J. Schmitz, Jr. (1988): Zonal velocity structure and transport in the Kuroshio Extension. J. Phys. Oceanogr., 18, 1484–1494.
Joyce, T. M., I. Yasuda, Y. Hiroe, K. Komatsu, K. Kawasaki and F. Bahr (2001): Mixing in the meadering Kuroshio Extension and the formation of NPIW. J. Geophys. Res. (in press).
Kalnay, E. and co-authors (1996): The NCEP/NCAR 40–year reanalysis project. Bull. Amer. Meteor. Soc., 77, 437–471.
Kawai, H. (1972): Hydrography of the Kuroshio Extension. p. 235–354. In Kuroshio—Its Physical Aspects, ed. by H. Stommel and K. Yoshida, University of Tokyo Press.
Kawai, H. and S. Saitoh (1986): Secondary fronts, warm tongues and warm streamers of the Kuroshio Extension system. Deep-Sea Res., 33, 1487–1507.
Kawamura, H., K. Mizuno and Y. Toba (1986): Formation process of a warm-core ring in the Kuroshio-Oyashio frontal zone—December 1982–October 1982. Deep-Sea Res., 33, 1617–1640.
Latif, M. and T. P. Barnett (1994): Causes of decadal climate variability over the North Pacific and North America. Science, 266, 634–637.
Latif, M. and T. P. Barnett (1996): Decadal climate variability over the North Pacific and North America: Dynamics and predictability. J. Climate, 9, 2407–2423.
Levitus, S. (1982): Climatological Atlas of the World Ocean. NOAA Prof. Paper No. 13, U.S. Government Printing Office, Washington, D.C., 173 pp.
Mantua, N. J., S. R. Hare, Y. Zhang, J. M. Wallace and R. C. Francis (1997): A Pacific interdecadal climate oscillation with impacts on salmon production. Bull. Amer. Meteor. Soc., 78, 1069–1079.
McCalpin, J. D. and D. B. Haidvogel (1996): Phenomenology of the low-frequency variability in a reduced-gravity, quasigeostrophic double-gyre model. J. Phys. Oceanogr., 26, 739–752.
Miller, A. J., D. R. Cayan, T. P. Barnett, N. E. Graham and J. M. Oberhuber (1994): Interdecadal variability of the Pacific Ocean: model response to observed heat flux and wind stress anomalies. Climate Dyn., 9, 287–302.
Miller, A. J., D. R. Cayan and W. B. White (1998): A westward-intensified decadal change in the North Pacific thermocline and gyre-scale circulation. J. Climate, 11, 3112–3127.
Mitchell, J. L., W. J. Teague, G. A. Jacobs and H. E. Hurlburt (1996): Kuroshio Extension dynamics from satellite altimetry and a model simulation. J. Geophys. Res., 101, 1045–1058.
Mizuno, K. and W. B. White (1983): Annual and interannual variability in the Kuroshio Current system. J. Phys. Oceanogr., 13, 1847–1867.
Nakamura, H. and A. S. Kazmin (2001): Decadal changes in the North Pacific oceanic frontal zones as revealed in ship and satellite observations. J. Geophys. Res. (submitted).
Nakamura, H., G. Lin and T. Yamagata (1997): Decadal climate variability in the North Pacific during the recent decades. Bull. Amer. Meteor. Soc., 78, 2215–2225.
Pedlosky, J. (1987): Geophysical Fluid Dynamics. Springer-Verlag, 710 pp.
Qiu, B. (1995): Variability and energetics of the Kuroshio Extension and its recirculation gyre from the first two-year TOPEX data. J. Phys. Oceanogr., 25, 1827–1842.
Qiu, B. (2000): Interannual variability of the Kuroshio Extension system and its impact on the wintertime SST field. J. Phys. Oceanogr., 30, 1486–1502.
Qiu, B. and R. X. Huang (1995): Ventilation of the North Atlantic and North Pacific: Subduction vs. obduction. J. Phys. Oceanogr., 25, 2374–2390.
Qiu, B. and T. M. Joyce (1992): Interannual variability in the mid-and low-latitude western North Pacific. J. Phys. Oceanogr., 22, 1062–1079.
Qiu, B. and K. A. Kelly (1993): Upper ocean heat balance in the Kuroshio Extension region. J. Phys. Oceanogr., 23, 2027–2041.
Qiu, B. and W. Miao (2000): Kuroshio path variations south of Japan: Bimodality as a self-sustained internal oscillation. J. Phys. Oceanogr., 30, 2471–2486.
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, 18,491–18,507.
Qu, T., H. Mitsudera and B. Qiu (2001): A climatology of the Kuroshio/Oyashio system east of Japan. J. Phys. Oceanogr., 31, 2575–2589.
Roden, G. I. (1998): Upper ocean thermohaline, oxygen, nutrient, and flow structure near the date line in summer of 1993. J. Geophys. Res., 103, 12,919–12,939.
Schmitz, W. J., Jr. (1984): Observations of the vertical structure of the eddy field in the Kuroshio Extension. J. Geophys. Res., 89, 6355–6364.
Schmitz, W. J., Jr., P. P. Niiler, R. L. Bernstein and W. R. Holland (1982): Recent long-term moored instrument observations in the western North Pacific. J. Geophys. Res., 87, 9425–9440.
Schmitz, W. J., Jr., P. P. Niiler and C. J. Koblinsky (1987): Two-year moored instrument results along 152°E. J. Geophys. Res., 92, 10,826–10,834.
Schneider, N. and A. J. Miller (2001): Predicting western North Pacific Ocean climate. J. Climate, 14, 3997–4002.
Schneider, N., A. J. Miller, M. A. Alexander and C. Deser (1999): Subduction of decadal North Pacific temperature anomalies: Observations and dynamics. J. Phys. Oceanogr., 29, 1056–1070.
Spall, M. A. (1996): Dynamics of the Gulf Stream/deep western boundary current crossover. Part II: Low-frequency internal oscillations. J. Phys. Oceanogr., 26, 2169–2182.
Suga, T. and K. Hanawa (1995): Interannual variations of North Pacific subtropical mode water in the 137°E section. J. Phys. Oceanogr., 25, 1012–1017.
Suga, T., Y. Takei and K. Hanawa (1997): Thermostad distribution in the North Pacific subtropical gyre: The central mode water and the subtropical mode water. J. Phys. Oceanogr., 27, 140–152.
Sugimoto, T., Y. Kawasaki and J. Li (1992): A description of the time-dependent hydrographic structure of the warm streamer around the Kuroshio warm-core ring 86B. Deep-Sea Res., 39, S77–S96.
Tai, C.-T. 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, 1761–1777.
Talley, L. (1997): North Pacific Intermediate Water transports in the mixed water region. J. Phys. Oceanogr., 27, 1795–1803.
Talley, L., Y. Nagata, M. Fujimura, T. Iwao, T. Kono, D. Inagake, M. Hirai and K. Okuda (1995): North Pacific Intermediate Water in the Kuroshio/Oyashio mixed water region. J. Phys. Oceanogr., 25, 475–501.
Tanimoto, Y., N. Iwasaka, K. Hanawa and Y. Toba (1993): Characteristic variations of sea surface temperature with multiple time scales in the North Pacific. J. Climate, 6, 1153–1160.
Tatebe, H. and I. Yasuda (2001): Seasonal axis migration of the upstream Kuroshio Extension associated with standing oscillations. J. Geophys. Res., 106, 16,685–16,692.
Teague, W. J., M. J. Carron and P. J. Hogan (1990): A comparison between the Generalized Digital Environmental Model and Levitus climatologies. J. Geophys. Res., 95, 7167–7183.
Toba, Y., J. Kimura, H. Murakami, M. Kim, Y. Yoshikawa and K. Shimada (2001): Unusual behavior of the Kuroshio current system from winter 1996 to summer 1997 revealed by ADEOS-OCTS and other data (continued): A study from broad external conditions with bottom topography. J. Oceanogr., 57, 141–154.
Wang, L., C. J. Koblinsky and S. Howden (1998): Annual and intra-annual sea level variability in the region of the Kuroshio Extension from TOPEX/POSEIDON and Geosat altimetry. J. Phys. Oceanogr., 28, 692–711.
White, W. B. (1995): Design of a global observing system for gyre-scale upper ocean temperature variability. Progr. Oceanogr., 36, 169–217.
White, W. B. and Y. He (1986): Interannual variability in the heat content of the Kuroshio Extension associated with the 1982 ENSO event. J. Phys. Oceanogr., 16, 309–321.
Wijffels, S. E., M. M. Hall, T. Joyce, D. J. Torres, P. Hacker and E. Firing (1998): Multiple deep gyres of the western North Pacific: A WOCE section along 149°E. J. Geophys. Res., 103, 12,985–13,009.
Wunsch, C. (1999): Where do ocean eddy heat fluxes matter? J. Geophys. Res., 104, 13,235–13,249.
Wyrtki, K. (1975): Fluctuations of the dynamic topography in the Pacific Ocean. J. Phys. Oceanogr., 5, 450–459.
Wyrtki, K., L. Magaard and J. Hagar (1976): Eddy energy in the oceans. J. Geophys. Res., 81, 2641–2646.
Xie, P. and P. A. Arkin (1997): Global precipitation: 17–year monthly analysis based on gauge observations, satellite estimates and numerical model outputs. Bull. Amer. Meteor. Soc., 78, 2539–2558.
Xie, S.-P., T. Kunitani, A. Kubokawa, M. Nonaka and S. Hosoda (2000): Interdecadal thermocline variability in the North Pacific for 1958–1997: A GCM simulation. J. Phys. Oceanogr., 30, 2798–2813.
Yamagata, T., Y. Shibao and S.-I. Umatani (1985): Interannual variability of the Kuroshio Extension and its relation to the Southern Oscillation/El Niño. J. Oceanogr. Soc. Japan, 41, 274–281.
Yasuda, I. (1997): The origin of the North Pacific Intermediate Water. J. Geophys. Res., 102, 893–909.
Yasuda, I., K. Okuda and M. Hirai (1992): Evolution of a Kuroshio warm-core ring—Variability of the hydrographic structure. Deep-Sea Res., 39, 131–161.
Yasuda, I., K. Okuda and Y. Shimizu (1996): Distribution and modification of North Pacific Intermediate Water in the Kuroshio-Oyashio inter-frontal zone. J. Phys. Oceanogr., 26, 448–465.
Yasuda, I., T. Tozuka, M. Noto and S. Kouketsu (2000): Heat balance and regime shifts of the mixed layer in the Kuroshio Extension. Progr. Oceanogr., 47, 257–278.
Yasuda, T. and K. Hanawa (1997): Decadal changes in the mode waters in the midlatitude North Pacific. J. Phys. Oceanogr., 27, 858–870.
Zhang, Y., J. M. Wallace and D. S. Battisti (1997): ENSO-life interdecadal variability: 1900–93. J. Climate, 10, 1004–1020.
About this article
Cite this article
Qiu, B. The Kuroshio Extension System: Its Large-Scale Variability and Role in the Midlatitude Ocean-Atmosphere Interaction. Journal of Oceanography 58, 57–75 (2002). https://doi.org/10.1023/A:1015824717293
- Kuroshio Extension
- recirculation gyre
- mixed layer heat balance
- midlatitude ocean-atmosphere coupling