Interdecadal Dynamics of the North Pacific Ocean

Guillermo Auad Climate Research Division, Scripps Institution of Oceanography, La Jolla, California

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Abstract

An isopycnal ocean model forced by NCEP–NCAR reanalysis wind stresses and heat fluxes is used to study the interdecadal variability of the Pacific Ocean in the 1958–97 period. A reasonable agreement is found between the model's modes of variability and those obtained by other researchers from both 100 years of observations and theoretical predictions. In agreement with previous observational work, decadal and interdecadal timescales have different descriptions, and from this study it is suggested that they indeed have different dynamics. This study focuses on the dynamics of the ocean's interdecadal variability, that is, of timescales of about 20 yr. The decadal timescale, that is, 10 yr, is briefly outlined and compared with previous studies. It is found that atmospheric heat fluxes play a key role in establishing the interdecadal SST pattern in the midlatitudinal North Pacific. These fluxes would excite a high baroclinic mode, igniting a series of events that move around the basin. In midlatitudes, interdecadal SSTs are most sensitive to the heat flux forcing along the eastern boundary north of about 30°N, in the western North Pacific at about 40°N, and along 20°N eastward of the date line; in the eastern North Pacific and north of 40°N, interdecadal pycnocline anomalies move across the Gulf of Alaska and toward the Aleutian Islands up to about the Kamchatka Peninsula, continuing to the southwest down to about 28°N. In their path, pycnocline oscillations induce SST changes in the Kuroshio–Oyashio Extension. On the other hand, in the eastern Tropics, the wind stress curl would induce interdecadal pycnocline oscillations that (between 10° and 20°N) propagate as Rossby waves, similar to those observed there for annual and interannual timescales, which, after crossing the date line, turn toward the north-northwest. All of these waves and/or events move or propagate within areas where the mean flow is of smaller amplitude than the phase speed in the direction of motion. In addition, the results presented here would suggest that a process similar to a servomechanism, and as envisaged by other authors, is present along 40°N, suggestive of an active ocean–atmosphere interaction over this area. Major differences are found between decadal and interdecadal dynamics.

Corresponding author address: Dr. Guillermo Auad, Climate Research Division, Scripps Institution of Oceanography, 9500 Gilman Drive, Dept. 0224, La Jolla, CA 92093-0224. Email: guillo@ucsd.edu

Abstract

An isopycnal ocean model forced by NCEP–NCAR reanalysis wind stresses and heat fluxes is used to study the interdecadal variability of the Pacific Ocean in the 1958–97 period. A reasonable agreement is found between the model's modes of variability and those obtained by other researchers from both 100 years of observations and theoretical predictions. In agreement with previous observational work, decadal and interdecadal timescales have different descriptions, and from this study it is suggested that they indeed have different dynamics. This study focuses on the dynamics of the ocean's interdecadal variability, that is, of timescales of about 20 yr. The decadal timescale, that is, 10 yr, is briefly outlined and compared with previous studies. It is found that atmospheric heat fluxes play a key role in establishing the interdecadal SST pattern in the midlatitudinal North Pacific. These fluxes would excite a high baroclinic mode, igniting a series of events that move around the basin. In midlatitudes, interdecadal SSTs are most sensitive to the heat flux forcing along the eastern boundary north of about 30°N, in the western North Pacific at about 40°N, and along 20°N eastward of the date line; in the eastern North Pacific and north of 40°N, interdecadal pycnocline anomalies move across the Gulf of Alaska and toward the Aleutian Islands up to about the Kamchatka Peninsula, continuing to the southwest down to about 28°N. In their path, pycnocline oscillations induce SST changes in the Kuroshio–Oyashio Extension. On the other hand, in the eastern Tropics, the wind stress curl would induce interdecadal pycnocline oscillations that (between 10° and 20°N) propagate as Rossby waves, similar to those observed there for annual and interannual timescales, which, after crossing the date line, turn toward the north-northwest. All of these waves and/or events move or propagate within areas where the mean flow is of smaller amplitude than the phase speed in the direction of motion. In addition, the results presented here would suggest that a process similar to a servomechanism, and as envisaged by other authors, is present along 40°N, suggestive of an active ocean–atmosphere interaction over this area. Major differences are found between decadal and interdecadal dynamics.

Corresponding author address: Dr. Guillermo Auad, Climate Research Division, Scripps Institution of Oceanography, 9500 Gilman Drive, Dept. 0224, La Jolla, CA 92093-0224. Email: guillo@ucsd.edu

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  • Alexander, M. A., C. Deser, and M. S. Timlin, 1999: The reemergence of SST anomalies in the North Pacific Ocean. J. Climate, 12 , 24192433.

    • Search Google Scholar
    • Export Citation
  • Anderson, P. J., and J. F. Piatt, 1999: Community reorganization in the Gulf of Alaska following ocean climate regime shift. Mar. Ecol. Prog. Ser., 189 , 117123.

    • Search Google Scholar
    • Export Citation
  • Auad, G., A. J. Miller, and W. B. White, 1998a: Simulation of heat storages and associated heat budgets in the Pacific Ocean, 1, El Niño-Southern Oscillation timescale. J. Geophys. Res., 103 , 2760327620.

    • Search Google Scholar
    • Export Citation
  • Auad, G., A. J. Miller, and W. B. White, 1998b: Simulation of heat storages and associated heat budgets in the Pacific Ocean, 2, Interdecadal timescale. J. Geophys. Res., 103 , 2762127635.

    • Search Google Scholar
    • Export Citation
  • Auad, G., A. J. Miller, J. O. Roads, and D. R. Cayan, 2001: Pacific Ocean wind stress and surface heat flux anomalies from NCEP reanalysis and observations: Cross-statistics and ocean model response. J. Geophys. Res., 106 , 2224922265.

    • Search Google Scholar
    • Export Citation
  • Barnett, T. P., M. Latif, E. Kirk, and E. Roeckner, 1991: On ENSO physics. J. Climate, 4 , 487515.

  • Barnett, T. P., D. W. Pierce, R. Saravanan, N. Schneider, D. Dommenget, and M. Latif, 1999: Origins of the midlatitude Pacific decadal variability. Geophys. Res. Lett., 26 , 14531456.

    • Search Google Scholar
    • Export Citation
  • Beamish, R. J., 1993: Climate and exceptional fish production off the west coast of North America. Can. J. Fish. Aquat. Sci., 50 , 22702291.

    • Search Google Scholar
    • Export Citation
  • Bjerknes, J., 1964: Atlantic air–sea interaction. Advances in Geophysics, Vol. 10, Academics Press, 1–82.

  • Bretherton, C. S., C. Smith, and J. M. Wallace, 1992: An intercomparison of methods for finding coupled patterns in climate data. J. Climate, 5 , 541560.

    • Search Google Scholar
    • Export Citation
  • Capotondi, A., and M. A. Alexander, 2001: Rossby waves in the tropical North Pacific and their role in decadal thermocline variability. J. Phys. Oceanogr., 31 , 34963515.

    • Search Google Scholar
    • Export Citation
  • Cayan, D. R., A. J. Miller, T. P. Barnett, N. E. Graham, J. N. Ritchie, and J. M. Oberhuber, 1995: Seasonal-interannual fluctuations in surface temperature over the Pacific: Effects of monthly winds and heat fluxes. Natural Climate Variability on Decadal-to-Century Time Scales, National Academy Press, 133–150.

    • Search Google Scholar
    • Export Citation
  • Cayan, D. R., A. A. Kammerdiener, M. D. Dettinger, J. M. Caprio, and D. H. Peterson, 2001: Changes in the onset of spring in the western United States. Bull. Amer. Meteor. Soc., 82 , 399415.

    • Search Google Scholar
    • Export Citation
  • Davis, R. E., 1976: Predictability of sea surface temperature and sea level pressure anomalies over the North Pacific Ocean. J. Phys. Oceanogr., 6 , 249266.

    • Search Google Scholar
    • Export Citation
  • Deser, C., and M. L. Blackmon, 1995: On the relationship between tropical and North Pacific sea surface temperature variations. J. Climate, 8 , 16771680.

    • Search Google Scholar
    • Export Citation
  • 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 , 16971706.

    • Search Google Scholar
    • Export Citation
  • Dettinger, M. D., D. S. Battisti, R. D. Garreaud, G. J. McCabe, and C. M. Bitz, 2000: Interhemispheric effects of interannual and decadal ENSO-like climate variations on the Americas. Present and Past Interhemispheric Climate Linkages in the Americas and their Societal Effects, V. Markgraf, Ed., Cambridge University Press, 1–16.

    • Search Google Scholar
    • Export Citation
  • Evans, M. N., M. A. Cane, D. P. Schrag, A. Kaplan, B. K. Linsley, R. Villalba, and G. M. Wellington, 2001: Support for tropically-driven Pacific decadal variability based on paleoproxy evidence. Geophys. Res. Lett., 28 , 36893692.

    • Search Google Scholar
    • Export Citation
  • Frankignoul, C., P. Muller, and E. Zorita, 1997: A simple model of the decadal response of the ocean to stochastic wind forcing. J. Phys. Oceanogr., 27 , 15331546.

    • Search Google Scholar
    • Export Citation
  • Garreaud, R. D., and D. S. Battisti, 1999: Interannual ENSO and interdecadal ENSO-like variability in the Southern Hemisphere tropospheric circulation. J. Climate, 12 , 21132123.

    • Search Google Scholar
    • Export Citation
  • Kaylor, R. E., 1977: Filtering and decimation of digital time series. Institute for Physical Science and Technology Tech. Rep. BN 850, University of Maryland, 42 pp.

    • Search Google Scholar
    • Export Citation
  • Kessler, W. S., 1990: Observations of long Rossby waves in the northern tropical Pacific. J. Geophy. Res., 95 , 51835217.

  • Killworth, P., 1996: Time interpolation of forcing fields in ocean models. J. Phys. Oceanogr., 26 , 136143.

  • Kirtman, B. P., and P. S. Schopf, 1998: Decadal variability in ENSO predictability and prediction. J. Climate, 11 , 28042822.

  • Latif, M., and T. Barnett, 1994: Causes of decadal climate variability over the North Pacific and North America. Science, 266 , 634637.

    • Search Google Scholar
    • Export Citation
  • Latif, M., and T. Barnett, 1996: Decadal climate variability over the North Pacific and North America—Dynamics and predictability. J. Climate, 9 , 24072423.

    • Search Google Scholar
    • Export Citation
  • Linsley, B. K., G. M. Wellington, and D. P. Schrag, 2000: Decadal sea surface temperature variability in the subtropical South Pacific from 1726 to 1997 a.d. Science, 290 , 11451148.

    • Search Google Scholar
    • Export Citation
  • Liu, Z., 1999: Forced planetary wave response in a thermocline gyre. J. Phys. Oceanogr., 29 , 10361055.

  • Lysne, J., and C. Deser, 2002: Wind-driven thermocline variability in the Pacific: A model–data comparison. J. Climate, 15 , 829845.

    • Search Google Scholar
    • Export Citation
  • Mantua, N. J., and S. R. Hare, 2002: The Pacific decadal oscillation. J. Oceanogr., 58 , 3544.

  • 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 , 10691079.

    • Search Google Scholar
    • Export Citation
  • Maximenko, N. A., P. P. Niiler, G. G. Panteleev, T. Yamagata, and D. B. Olson, 2002: Near-surface dynamical structure of the Kuroshio Extension derived from drifter and altimetry data. Exchanges, 7 , 14.

    • Search Google Scholar
    • Export Citation
  • Mestas-Nuñez, A., and D. B. Enfield, 1999: Rotated global modes of non-ENSO sea surface temperature variability. J. Climate, 12 , 27342746.

    • Search Google Scholar
    • Export Citation
  • Miller, A. J., and N. Schneider, 2000: Interdecadal climate regime dynamics in the North Pacific Ocean: Theories, observations and ecosystem impacts. Progress in Oceanography, Vol. 47, Pergamon, 355–379.

    • Search Google Scholar
    • Export Citation
  • Miller, A. J., D. R. Cayan, T. P. Barnett, N. E. Graham, and J. M. Oberhuber, 1994a: The 1976–77 climate shift of the Pacific Ocean. Oceanography, 7 , 2126.

    • Search Google Scholar
    • Export Citation
  • Miller, A. J., D. R. Cayan, T. P. Barnett, N. E. Graham, and J. M. Oberhuber, 1994b: Interdecadal variability of the Pacific Ocean: Model response to observed heat flux and wind stress anomalies. Climate Dyn., 9 , 287302.

    • Search Google Scholar
    • Export Citation
  • Miller, A. J., W. B. White, and D. R. Cayan, 1997: North Pacific thermocline variations on ENSO timescales. J. Phys. Oceanogr., 27 , 20232039.

    • Search Google Scholar
    • Export Citation
  • 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 , 31123127.

    • Search Google Scholar
    • Export Citation
  • Minobe, S., 2000: Spatio-temporal structure of the pentadecadal variability over the North Pacific. Progress in Oceanography, Vol. 47, Pergamon, 381–408.

    • Search Google Scholar
    • Export Citation
  • Nakamura, H., G. Lin, and T. Yamagata, 1997: Decadal climate variability in the North Pacific during recent decades. Bull. Amer. Meteor. Soc., 78 , 22152225.

    • Search Google Scholar
    • Export Citation
  • Oberhuber, J. M., 1993: Simulation of the Atlantic circulation with a coupled sea ice–mixed layer–isopycnal general circulation model. Part I: Model description. J. Phys. Oceanogr., 23 , 808829.

    • Search Google Scholar
    • Export Citation
  • Pedlosky, J., 1979: Geophysical Fluid Dynamics. Springer-Verlag, 624 pp.

  • Peng, S., and J. S. Whitaker, 1999: Mechanisms for determining the atmospheric response to midlatitude SST anomalies. J. Climate, 12 , 13931408.

    • Search Google Scholar
    • Export Citation
  • Peng, S., W. A. Robinson, and M. P. Hoerling, 1997: The modeled atmospheric response to midlatitude SST anomalies and its dependency on background circulation states. J. Climate, 10 , 971987.

    • Search Google Scholar
    • Export Citation
  • Pierce, D. W., T. P. Barnett, N. Schneider, R. Saravanan, D. Dommenget, and M. Latif, 2001: The role of ocean dynamics in producing decadal climate variability in the North Pacific. Climate Dyn., 18 , 5170.

    • Search Google Scholar
    • Export Citation
  • Qiu, B., 1995: Why is the spreading of the North Pacific Intermediate Water confined on density surfaces around σ = 26.8? J. Phys. Oceanogr., 25 , 168180.

    • Search Google Scholar
    • Export Citation
  • Qiu, B., and K. A. Kelly, 1993: Upper-ocean heat balance in the Kuroshio–Oyashio Extension region. J. Phys. Oceanogr., 23 , 20272041.

    • Search Google Scholar
    • Export Citation
  • Reed, R. K., J. D. Schumacher, P. J. Stabeno, C. H. Pease, A. W. Kendall Jr., and P. Dell'Arciprete, 1994: Alaskan Stream inflow and effects in the Bering Sea. Eos, Trans. Amer. Geophys. Union, 75 , 342.

    • Search Google Scholar
    • Export Citation
  • Reynolds, R. W., and T. M. Smith, 1994: Improved global sea surface temperature analyses. J. Climate, 7 , 929948.

  • Ripa, P., 1986: Evaluation of vertical structure functions for the analysis of oceanic data. J. Phys. Oceanogr., 16 , 223232.

  • Robertson, A. W., 1996: Interdecadal variability in a multicentury climate integration. Climate Dyn., 12 , 227241.

  • Schneider, N., and A. J. Miller, 2001: Predicting western North Pacific Ocean climate. J. Climate, 14 , 39974002.

  • Schneider, N., A. J. Miller, and D. W. Pierce, 2002: Anatomy of North Pacific decadal variability. J. Climate, 15 , 586605.

  • Seager, R., M. B. Blumenthal, and Y. Kushnir, 1995: An advective atmospheric mixed layer model for ocean modeling purposes: Global simulation of surface heat fluxes. J. Climate, 8 , 19511964.

    • Search Google Scholar
    • Export Citation
  • Seager, R., Y. Kushnir, N. H. Naik, M. A. Cane, and J. Miller, 2001: Wind-driven shifts in the latitude of the Kuroshio–Oyashio Extension and generation of SST anomalies on decadal timescales. J. Climate, 14 , 42494265.

    • Search Google Scholar
    • Export Citation
  • Stabeno, P. J., and R. K. Reed, 1994: Circulation in the Bering Sea basin by satellite-tracked drifters: 1986–1993. J. Phys. Oceanogr., 24 , 848854.

    • Search Google Scholar
    • Export Citation
  • Tourre, Y., W. B. White, and Y. Kushnir, 1999: Evolution of interdecadal variability in sea level pressure, sea surface temperature and upper-ocean temperature over the Pacific Ocean. J. Phys. Oceanogr., 29 , 15281541.

    • Search Google Scholar
    • Export Citation
  • Tourre, Y., B. Rajagopalan, Y. Kushnir, M. Barlow, and W. B. White, 2001: Patterns of coherent decadal and interdecadal climate signals in the Pacific basin during the 20th century. Geophys. Res. Lett., 28 , 20692072.

    • Search Google Scholar
    • Export Citation
  • Trenberth, K. E., 1990: Recent observed interdecadal climate changes in the Northern Hemisphere. Bull. Amer. Meteor. Soc., 71 , 988993.

    • Search Google Scholar
    • Export Citation
  • White, W. B., and T. P. Barnett, 1972: A servomechanism in the ocean/atmosphere system of the midlatitude North Pacific Ocean. J. Phys. Oceanogr., 2 , 372381.

    • Search Google Scholar
    • Export Citation
  • White, W. B., and D. R. Cayan, 1998: Quasi-periodicity and global symmetries in interdecadal upper ocean temperature variability. J. Geophys. Res., 103 , 2133521354.

    • Search Google Scholar
    • Export Citation
  • White, W. B., J. Lean, D. Cayan, and M. Dettinger, 1997: Response of global upper ocean temperature to changing solar irradiance. J. Geophys. Res., 102 , 32553266.

    • Search Google Scholar
    • Export Citation
  • Xie, S. P., T. Kunitani, A. Kubokawa, M. Nonada, and S. Hosoda, 2000: Interdecadal thermocline variability in the North Pacific for 1958–1997: A GCM simulation. J. Phys. Oceanogr., 30 , 27982813.

    • Search Google Scholar
    • Export Citation
  • Zhang, R. H., and S. Levitus, 1997: Structure and cycle of decadal variability of upper-ocean temperature in the North Pacific. J. Climate, 10 , 710727.

    • Search Google Scholar
    • Export Citation
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