• Aoki, S., M. Hariyama, H. Mitsudera, H. Sasaki, and Y. Sasai, 2007: Formation regions of Subantarctic Mode Water detected by OFES and Argo profiling floats. Geophys. Res. Lett., 34, L10606, doi:10.1029/2007GL029828.

    • Search Google Scholar
    • Export Citation
  • Chen, J., T. Qu, Y. N. Sasaki, and N. Schneider, 2010: Anti-correlated variability in subduction rate of the western and eastern North Pacific Oceans identified by an eddy-resolving ocean GCM. Geophys. Res. Lett., 37, L23608, doi:10.1029/2010GL045239.

    • Search Google Scholar
    • Export Citation
  • Dutrieux, P., 2009: Tropical Western Pacific currents and the origin of intraseasonal variability below the thermocline. Ph.D. thesis, University of Hawaii at Manoa, 150 pp.

  • Firing, E., Y. Kashino, and P. Hacker, 2005: Energetic subthermocline currents observed east of Mindanao. Deep-Sea Res. II, 52 (3–4), 605613, doi:10.1016/j.dsr2.2004.12.007.

    • Search Google Scholar
    • Export Citation
  • Johnson, G. C., and K. E. McTaggart, 2010: Equatorial Pacific 13°C Water eddies in the eastern subtropical South Pacific Ocean. J. Phys. Oceanogr., 40, 226236.

    • Search Google Scholar
    • Export Citation
  • Kashino, Y., H. Watanabe, B. Herunadi, M. Aoyama, and D. Hartoyo, 1999: Current variability at the Pacific entrance of the Indonesian Throughflow. J. Geophys. Res., 104 (C5), 11 02111 035.

    • Search Google Scholar
    • Export Citation
  • Kashino, Y., A. Ishida, and Y. Kuroda, 2005: Variability of the Mindanao Current: Mooring observation results. Geophys. Res. Lett., 32, L18611, doi:10.1029/2005GL023880.

    • Search Google Scholar
    • Export Citation
  • Kashino, Y., I. Ueki, Y. Kuroda, and A. Purwandani, 2007: Ocean variability north of New Guinea derived from TRITON buoy data. J. Oceanogr., 63, 545559, doi:10.1007/s10872-007-0049-y.

    • Search Google Scholar
    • Export Citation
  • Kashino, Y., N. N. España, F. Syamsudin, K. J. Richards, T. Jensen, P. Dutrieux, and A. Ishida, 2009: Observations of the North Equatorial Current, Mindanao Current, and Kuroshio Current System during the 2006/07 El Niño and 2007/08 La Niña. J. Oceanogr., 65, 325333, doi:10.1007/s10872-009-0030-z.

    • Search Google Scholar
    • Export Citation
  • Kawabe, M., Y. Kashino, and Y. Kuroda, 2008: Variability and linkages of New Guinea Coastal Undercurrent and Lower Equatorial Intermediate Current. J. Phys. Oceanogr., 38, 17801793.

    • Search Google Scholar
    • Export Citation
  • Kuroda, Y., 2000: Variability of currents off the northern coast of New Guinea. J. Oceanogr., 56, 103116, doi:10.1023/A:1011122810354.

    • Search Google Scholar
    • Export Citation
  • Lindstrom, E., R. Lukas, R. Fine, E. Firing, S. Godfrey, G. Meyers, and M. Tsuchiya, 1987: The western equatorial Pacific Ocean circulation study. Nature, 330, 533537, doi:10.1038/330533a0.

    • Search Google Scholar
    • Export Citation
  • Masina, S., S. G. H. Philander, and A. B. G. Bush, 1999: An analysis of tropical instability waves in a numerical model of the Pacific Ocean: 2. Generation and energetics of the waves. J. Geophys. Res., 104 (C12), 69 63729 661.

    • Search Google Scholar
    • Export Citation
  • Masumoto, Y., and Coauthors, 2004: A fifty-year eddy-resolving simulation of the world ocean—Preliminary outcomes of OFES (OGCM for the Earth Simulator). J. Earth Simul., 1, 3556.

    • Search Google Scholar
    • Export Citation
  • Qu, T., and E. J. Lindstrom, 2004: Northward intrusion of Antarctic Intermediate Water in the western Pacific. J. Phys. Oceanogr., 34, 21042118.

    • Search Google Scholar
    • Export Citation
  • Qu, T., J. Gan, A. Ishida, Y. Kashino, and T. Tozuka, 2008: Semiannual variation in the western tropical Pacific Ocean. Geophys. Res. Lett., 35, L16602, doi:10.1029/2008GL035058.

    • Search Google Scholar
    • Export Citation
  • Qu, T., T.-L. Chiang, C.-R. Wu, P. Dutrieux, and D. Hu, 2012: Mindanao Current/Undercurrent in an eddy-resolving GCM. J. Geophys. Res., 117, C06026, doi:10.1029/2011JC007838.

    • Search Google Scholar
    • Export Citation
  • Reid, J. L., 1965: Intermediate Waters of the Pacific Ocean. Johns Hopkins Oceanographic Studies, No. 2, Johns Hopkins Press, 85 pp.

  • Richardson, P. L., A. S. Bower, and W. Zenk, 2000: A census of Meddies tracked by floats. Prog. Oceanogr., 45, 209250, doi:10.1016/S0079-6611(99)00053-1.

    • Search Google Scholar
    • Export Citation
  • Sasaki, H., M. Nonaka, Y. Masumoto, Y. Sasai, H. Uehara, and H. Sakuma, 2008: An eddy-resolving hindcast simulation of the quasiglobal ocean from 1950 to 2003 on the Earth Simulator. High Resolution Numerical Modelling of the Atmosphere and Ocean, K. Hamilton and W. Ohfuchi, Eds., Springer, 157–185.

  • Shapiro, G. I., and S. L. Meschanov, 1991: Distribution and spreading of Red Sea Water and salt lens formation in the northwest Indian Ocean. Deep-Sea Res., 38A, 2134, doi:10.1016/0198-0149(91)90052-H.

    • Search Google Scholar
    • Export Citation
  • Simpson, J. J., and R. J. Lynn, 1990: A mesoscale eddy dipole in the offshore California Current. J. Geophys. Res., 95 (C8), 13 00913 022.

    • Search Google Scholar
    • Export Citation
  • Wijffels, S., E. Firing, and J. Toole, 1995: The mean structure and variability of the Mindanao Current at 8°N. J. Geophys. Res., 100 (C9), 18 42118 435.

    • Search Google Scholar
    • Export Citation
  • Zenk, W., G. Siedler, A. Ishida, J. Holfort, Y. Kashino, Y. Kuroda, T. Miyama, and T. J. Müller, 2005: Pathways and variability of the Antarctic Intermediate Water in the western equatorial Pacific Ocean. Prog. Oceanogr., 67 (1–2), 245281, doi:10.1016/j.pocean.2005.05.003.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 3 3 3
PDF Downloads 2 2 2

Subthermocline Eddies in the Western Equatorial Pacific as Shown by an Eddy-Resolving OGCM

View More View Less
  • 1 Department of Earth Sciences, National Taiwan Normal University, Taipei, Taiwan, and International Pacific Research Center, SOEST, University of Hawaii at Manoa, Honolulu, Hawaii
  • | 2 International Pacific Research Center, SOEST, University of Hawaii at Manoa, Honolulu, Hawaii
Restricted access

Abstract

Sporadic in situ observations have shown evidence that subthermocline eddies exist off the Mindanao coast. These subthermocline eddies are believed to play an important role in the heat, freshwater, and other ocean property transports of the region, but their characteristics and in particular their pathway and source of energy are poorly explored because of the lack of long-term observations. Analysis of results from an eddy-resolving general ocean circulation model has revealed that most subthermocline eddies off the Mindanao coast originate from the equatorial South Pacific Ocean to the west of the Ninigo Group. These eddies propagate northward along the New Guinea coast, cross the equator in the far western Pacific, and reach the Mindanao coast at a typical propagation speed of ~0.12 m s−1. The dominant time scales of these eddies range between 50 and 60 days.

School of Ocean and Earth Science and Technology Contribution Number 8928 and International Pacific Research Center Contribution Number 981.

Corresponding author address: Dr. Tangdong Qu, International Pacific Research Center, SOEST, University of Hawaii at Manoa, 1680 East-West Road, Honolulu, HI 96822. E-mail: tangdong@hawaii.edu

Abstract

Sporadic in situ observations have shown evidence that subthermocline eddies exist off the Mindanao coast. These subthermocline eddies are believed to play an important role in the heat, freshwater, and other ocean property transports of the region, but their characteristics and in particular their pathway and source of energy are poorly explored because of the lack of long-term observations. Analysis of results from an eddy-resolving general ocean circulation model has revealed that most subthermocline eddies off the Mindanao coast originate from the equatorial South Pacific Ocean to the west of the Ninigo Group. These eddies propagate northward along the New Guinea coast, cross the equator in the far western Pacific, and reach the Mindanao coast at a typical propagation speed of ~0.12 m s−1. The dominant time scales of these eddies range between 50 and 60 days.

School of Ocean and Earth Science and Technology Contribution Number 8928 and International Pacific Research Center Contribution Number 981.

Corresponding author address: Dr. Tangdong Qu, International Pacific Research Center, SOEST, University of Hawaii at Manoa, 1680 East-West Road, Honolulu, HI 96822. E-mail: tangdong@hawaii.edu
Save