Journal of Oceanography

, Volume 68, Issue 1, pp 5–20 | Cite as

Progress of North Pacific mode water research in the past decade

  • Eitarou OkaEmail author
  • Bo Qiu
Special Section: Review New developments in mode-water research: Dynamic and climatic effects


This article reviews the progress in research on North Pacific mode waters of the past decade from the physical oceanographic perspective. The accumulation of satellite altimeter sea surface height data, the rapid growth of the Argo profiling float array, and the advancement in eddy-resolving ocean general circulation models have greatly improved the traditional views on the mode waters that were formed prior to the 1990s based on the analyses of historical temperature/salinity data. Areas where significant progress was made include: (1) descriptions of the mode waters’ distributions and properties with fine spatial scales, particularly in their formation regions in winter where observational data had been insufficient; (2) clarifications of the mode waters’ formation and subduction processes relating to the large-scale mean circulation, as well as to the time-varying mesoscale eddy field; (3) impacts of the mode waters’ circulation and dissipation processes on the climate and biogeochemical processes; and (4) dynamic versus thermodynamic causes underlying the mode waters’ decadal changes. In addition to the review, future directions for mode water research are also presented.


Mode waters North Pacific Physical oceanography Seasonal to decadal variability Eddy modifications Climate and biogeochemical impacts 



The authors thank Atsushi Kubokawa for the opportunity to write this review and two anonymous reviewers for helpful comments on the manuscript. This review is based on discussions by the authors in summer 2010 when EO visited the University of Hawaii at Manoa for 1 month under the Overseas Internship Program for Outstanding Young Earth and Planetary Researchers provided by the Department of Earth and Planetary Science, the University of Tokyo. EO is also supported by the Japan Society for Promotion of Science [KAKENHI, Grant-in-Aid for Scientific Research (B), no. 21340133] and the Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT; Grant-in-Aid for Scientific Research on Innovative Areas under grant no. 22106007). BQ is supported by NSF through grant OCE-0926594 and NASA through contract 1207881 as part of NASA’s Ocean Surface Topography Mission.


  1. Andreev AG, Kusakabe M (2001) Interdecadal variability in dissolved oxygen in the intermediate water layer of the western subarctic gyre and Kuril Basin (Okhotsk Sea). Geophys Res Lett 28:2453–2456CrossRefGoogle Scholar
  2. Aoki Y, Suga T, Hanawa K (2002) Subsurface subtropical fronts of the North Pacific as inherent boundaries in the ventilated thermocline. J Phys Oceanogr 32:2299–2311CrossRefGoogle Scholar
  3. Bates NR, Pequignet AC, Johnson RJ, Gruber N (2002) A variable sink for atmospheric CO2 in subtropical mode water of the North Atlantic Ocean. Nature 420:489–493CrossRefGoogle Scholar
  4. Bingham FM (1992) Formation and spreading of subtropical mode water in the North Pacific. J Geophys Res 97:11177–11189CrossRefGoogle Scholar
  5. Bingham FM, Suga T (2006) Distributions of mixed layer properties in North Pacific water mass formation areas: comparison of Argo floats and World Ocean Atlas 2001. Ocean Sci 2:61–70CrossRefGoogle Scholar
  6. Bingham FM, Suga T, Hanawa K (1992) Comparison of upper ocean thermal conditions in the western North Pacific between two pentads: 1938–42 and 1978–82. J Oceanogr 48:405–425CrossRefGoogle Scholar
  7. Cannon GA (1966) Tropical waters in the western Pacific Oceans, August–September 1957. Deep Sea Res 13:1139–1148Google Scholar
  8. Cronin MF, Meinig C, Sabine CL, Ichikawa H, Tomita H (2008) Surface mooring network in the Kuroshio Extension. IEEE Syst J 2:424–430CrossRefGoogle Scholar
  9. Davis XJ, Rothstein LM, Dewar WK, Menemenlis D (2011) Numerical investigations of seasonal and interannual variability of North Pacific Subtropical Mode water and its implications for Pacific climate variability. J Clim (in press)Google Scholar
  10. de Boyer Montégut C, Madec G, Fischer AS, Lazar A, Iudicone D (2004) Mixed layer depth over the global ocean: an examination of profile data and a profile-based climatology. J Geophys Res 109:C12003. doi: 10.1029/2004JC002378 CrossRefGoogle Scholar
  11. Deser C, Alexander MA, Timlin MS (1996) Upper-ocean thermal variations in the North Pacific during 1970–1991. J Clim 9:1840–1855CrossRefGoogle Scholar
  12. Ebuchi N, Hanawa K (2001) Trajectory of mesoscale eddies in the Kuroshio recirculation region. J Oceanogr 57:471–480CrossRefGoogle Scholar
  13. Emerson S, Watanabe YW, Ono T, Mecking S (2004) Temporal trends in apparent oxygen utilization in the upper pycnocline of the North Pacific: 1980–2000. J Oceanogr 60:139–147CrossRefGoogle Scholar
  14. Endoh T, Jia Y, Richards KJ (2006) Sensitivity of the ventilation process in the North Pacific to eddy-induced tracer transport. J Phys Oceanogr 36:1895–1911CrossRefGoogle Scholar
  15. Favorite F, Dodimead AJ, Nasu K (1976) Oceanography of the Subarctic Pacific region, 1960–71. Bull Int North Pac Comm 33:1–187Google Scholar
  16. Freeland H, Roemmich D, Garzoli S, LeTraon P, Ravichandran M, Riser S, Thierry V, Wijffels S, Belbeoch M, Gould J, Grant F, Ignazewski M, King B, Klein B, Mork K, Owens B, Pouliquen S, Sterl A, Suga T, Suk M, Sutton P, Troisi A, Velez-Belchi P, Xu J (2010) Argo—a decade of progress. In: Hall J, Harrison DE, Stammer D (eds) Proceedings of OceanObs’09: sustained ocean observations and information for society, 21–25 September 2009, vol 2. ESA Publication WPP-306, Venice, Italy. doi: 10.5270/OceanObs09.cwp.32
  17. Graham NE (1994) Decadal-scale climate variability in the 1970s and 1980s: observations and model results. Clim Dyn 10:135–159CrossRefGoogle Scholar
  18. Gregg MC, Sanford TB (1980) Signatures of mixing from the Bermuda Slope, the Sargasso Sea and the Gulf Stream. J Phys Oceanogr 10:105–127CrossRefGoogle Scholar
  19. Gu D, Philander SGH (1997) Interdecadal climate fluctuations that depend on exchanges between the tropics and extratropics. Science 275:805–807CrossRefGoogle Scholar
  20. Hanawa K (1987) Interannual variations of the winter-time outcrop area of subtropical mode water in the western North Pacific Ocean. Atmos Ocean 25:358–374CrossRefGoogle Scholar
  21. Hanawa K (1996) Interdecadal variability in the North Pacific Ocean: subduction oscillation. Paper presented at WOCE pacific workshop, U.S. WOCE Office, Newport Beach, CA, August 19–23Google Scholar
  22. Hanawa K, Hoshino I (1988) Temperature structure and mixed layer in the Kuroshio region over the Izu Ridge. J Mar Res 46:683–700CrossRefGoogle Scholar
  23. Hanawa K, Kamada J (2001) Variability of core layer temperature (CLT) of the North Pacific subtropical mode water. Geophys Res Lett 28:2229–2232CrossRefGoogle Scholar
  24. Hanawa K, Sugimoto S (2004) ‘Reemergence’ areas of winter sea surface temperature anomalies in the world’s oceans. Geophys Res Lett 31:L10303. doi: 10.1029/2004GL019904 CrossRefGoogle Scholar
  25. Hanawa K, Talley LD (2001) Mode waters. In: Church J et al (eds) Ocean circulation and climate. Academic Press, London, pp 373–386CrossRefGoogle Scholar
  26. Hanawa K, Yoritaka H (2001) North Pacific subtropical mode waters observed in long XBT cross sections along 32.5°N line. J Oceanogr 57:679–692CrossRefGoogle Scholar
  27. Hare SR (1996) Low frequency climate variability and salmon production. Ph.D. dissertation, University of Washington, Seattle, WAGoogle Scholar
  28. Hasumi H, Tatebe H, Kawasaki T, Kurogi M, Sakamoto TT (2010) Progress of North Pacific modeling over the past decade. Deep Sea Res II 57:1188–1200CrossRefGoogle Scholar
  29. Hautala SL, Roemmich DH (1998) Subtropical mode water in the Northeast Pacific basin. J Geophys Res 103:13055–13066CrossRefGoogle Scholar
  30. Hazeleger W, Drijfhout SS (2000) Eddy subduction in a model of the subtropical gyre. J Phys Oceanogr 30:677–695CrossRefGoogle Scholar
  31. Hosoda S, Xie SP, Takeuchi K, Nonaka M (2001) Eastern North Pacific subtropical mode water in a GCM: formation mechanism and salinity effects. J Geophys Res 106:19671–19681CrossRefGoogle Scholar
  32. Hosoda S, Xie SP, Takeuchi K, Nonaka M (2004) Interdecadal temperature variations in the North Pacific central mode water simulated by an OGCM. J Oceanogr 60:865–877Google Scholar
  33. Huang RX, Qiu B (1994) Three-dimensional structure of the wind-driven circulation in the subtropical North Pacific. J Phys Oceanogr 24:1608–1622CrossRefGoogle Scholar
  34. Inui T, Takeuchi K, Hanawa K (1999) A numerical investigation of the subduction process in response to an abrupt intensification of westerlies. J Phys Oceanogr 29:1993–2015CrossRefGoogle Scholar
  35. Isoguchi O, Kawamura H, Oka E (2006) Quasi-stationary jets transporting surface warm waters across the transition zone between the subtropical and the subarctic gyres in the North Pacific. J Geophys Res 111:C10003. doi: 10.1029/2005JC003402 CrossRefGoogle Scholar
  36. Itoh S, Yasuda I (2010a) Characteristics of mesoscale eddies in the Kuroshio-Oyashio Extension region detected from the distribution of the sea surface height anomaly. J Phys Oceanogr 40:1018–1034CrossRefGoogle Scholar
  37. Itoh S, Yasuda I (2010b) Water mass structure of warm and cold anticyclonic eddies in the western boundary region of the subarctic North Pacific. J Phys Oceanogr 40:2624–2642CrossRefGoogle Scholar
  38. Itoh S, Shimizu Y, Ito S, Yasuda I (2011) Evolution and decay of a warm-core ring within the western subarctic gyre of the North Pacific, as observed by profiling floats. J Oceanogr (in press)Google Scholar
  39. Iwamaru H, Kobashi F, Iwasaka N (2010) Temporal variations of the winter mixed layer south of the Kuroshio extension. J Oceanogr 66:147–153CrossRefGoogle Scholar
  40. Jensen TG, Campbell TJ, Allard RA, Small RJ, Smith TA (2011) Turbulent heat fluxes during an intense cold-air outbreak over the Kuroshio Extension Region: results from a high-resolution coupled atmosphere–ocean model. Ocean Dyn 61:657–674Google Scholar
  41. Joyce TM (2011) New perspectives on Eighteen Degree Water formation in the North Atlantic. J Oceanogr (this issue)Google Scholar
  42. Kako S, Kubota M (2007) Variability of mixed layer depth in Kuroshio/Oyashio Extension region: 2005–2006. Geophys Res Lett 34:L11612. doi: 10.1029/2007GL030362 CrossRefGoogle Scholar
  43. Kawabe M (1995) Variations of current path, velocity, and volume transport of the Kuroshio in relation with the large meander. J Phys Oceanogr 25:3103–3117CrossRefGoogle Scholar
  44. Kawai H (1972) Hydrography of the Kuroshio Extension. In: Stommel H, Yoshida K (eds) Kuroshio—its physical aspects. University of Tokyo Press, Tokyo, pp 235–352Google Scholar
  45. Kelly KA, Thompson L, Cheng W, Metzger EJ (2007) Evaluation of HYCOM in the Kuroshio Extension region using new metrics. J Geophys Res 112:C01004. doi: 10.1029/2006JC003614 CrossRefGoogle Scholar
  46. Kelly KA, Small RJ, Samelson RM, Qiu B, Joyce T, Cronin M, Kwon YO (2010) Western boundary currents and frontal air-sea interaction: Gulf Stream and Kuroshio Extension. J Clim 23:5644–5667CrossRefGoogle Scholar
  47. Kobashi F, Kubokawa A (2011) Review on North Pacific Subtropical Countercurrent and Subtropical Front: role of mode water in ocean circulation and climate. J Oceanogr (this issue)Google Scholar
  48. Kobashi F, Xie SP (2011) Interannual variability of the North Pacific Subtropical Countercurrent: role of local ocean–atmosphere interaction. J Oceanogr (this issue)Google Scholar
  49. Kobashi F, Mitsudera H, Xie SP (2006) Three subtropical fronts in the North Pacific: observational evidence for mode water-induced subsurface frontogenesis. J Geophys Res 111:C09033. doi: 10.1029/2006JC003479 CrossRefGoogle Scholar
  50. Kobashi F, Xie SP, Iwasaka N, Sakamoto TT (2008) Deep atmospheric response to the North Pacific oceanic subtropical front in spring. J Clim 21:5960–5975CrossRefGoogle Scholar
  51. Kouketsu S, Tomita H, Oka E, Hosoda S, Kobayashi T, Sato K (2011) The role of meso-scale eddies in mixed layer deepening and mode water formation in the western North Pacific. J Oceanogr (this issue)Google Scholar
  52. Krémeur AS, Lévy M, Aumont O, Reverdin G (2009) Impact of the subtropical mode water biogeochemical properties on primary production in the North Atlantic: new insights from an idealized model study. J Geophys Res 114:C07019. doi: 10.1029/2008JC005161 CrossRefGoogle Scholar
  53. Kubokawa A (1997) A two-level model of subtropical gyre and subtropical countercurrent. J Oceanogr 53:231–244Google Scholar
  54. Kubokawa A (1999) Ventilated thermocline strongly affected by a deep mixed layer: a theory for subtropical countercurrent. J Phys Oceanogr 29:1314–1333CrossRefGoogle Scholar
  55. Kubokawa A, Inui T (1999) Subtropical countercurrent in an idealized ocean GCM. J Phys Oceanogr 29:1303–1313CrossRefGoogle Scholar
  56. Kubokawa A, Xie SP (2002) On steady response of a ventilated thermocline to enhanced Ekman pumping. J Oceanogr 58:565–575CrossRefGoogle Scholar
  57. Ladd C, Thompson L (2000) Formation mechanisms for North Pacific central and eastern subtropical mode waters. J Phys Oceanogr 30:868–887CrossRefGoogle Scholar
  58. Ladd C, Thompson L (2001) Water mass formation in an isopycnal model of the North Pacific. J Phys Oceanogr 31:1517–1537CrossRefGoogle Scholar
  59. Ladd C, Thompson L (2002) Decadal variability of North Pacific central mode water. J Phys Oceanogr 32:2870–2881CrossRefGoogle Scholar
  60. Ledwell JR, Watson AJ, Law CD (1993) Evidence for slow mixing across the pycnocline from an open-ocean tracer release experiment. Nature 364:701–703CrossRefGoogle Scholar
  61. Lee HC (2009) Impact of atmospheric CO2 doubling on the North Pacific subtropical mode water. Geophys Res Lett 36:L06602. doi: 10.1029/2008GL037075 CrossRefGoogle Scholar
  62. Liu Q, Hu H (2007) A subsurface pathway for low potential vorticity transport from the central North Pacific toward Taiwan Island. Geophys Res Lett 34:L12710. doi: 10.1029/2007GL029510 CrossRefGoogle Scholar
  63. Luo Y, Liu Q, Rothstein LM (2009) Simulated response of North Pacific mode waters to global warming. Geophys Res Lett 36:L23609. doi: 10.1029/2009GL040906 CrossRefGoogle Scholar
  64. Luyten JR, Pedlosky J, Stommel H (1983) The ventilated thermocline. J Phys Oceanogr 13:292–309CrossRefGoogle Scholar
  65. Mantua NJ, Hare SR (2002) The Pacific decadal oscillation. J Oceanogr 58:35–44CrossRefGoogle Scholar
  66. Mantua NJ, Hare SR, Zhang Y, Wallace JM, Francis RC (1997) A Pacific interdecadal climate oscillation with impacts on salmon production. Bull Am Meteorol Soc 78:1069–1079CrossRefGoogle Scholar
  67. Marshall D (1997) Subduction of water masses in an eddying ocean. J Mar Res 55:201–222CrossRefGoogle Scholar
  68. Marshall JC, Nurser AJG, Williams RG (1993) Inferring the subduction rate and period over the North Atlantic. J Phys Oceanogr 23:1315–1329CrossRefGoogle Scholar
  69. Masumoto Y (2010) Sharing the results of a high-resolution ocean general circulation model under a multi-discipline framework—a review of OFES activities. Ocean Dyn 60:633–652CrossRefGoogle Scholar
  70. Masuzawa J (1969) Subtropical mode water. Deep Sea Res 16:463–472Google Scholar
  71. Mecking S, Warner MJ (2001) On the subsurface CFC maxima in the subtropical North Pacific thermocline and their relation to mode waters and oxygen maxima. J Geophys Res 106:22179–22198CrossRefGoogle Scholar
  72. Mecking S, Langdon C, Feely RA, Sabine CL, Deutsch CA, Min DH (2008) Climate variability in the North Pacific thermocline diagnosed from oxygen measurements: an update based on the U.S. CLIVAR/CO2 repeat hydrography cruises. Glob Biogeochem Cycles 22:GB3015. doi: 10.1029/2007GB003101
  73. Miyazawa Y, Zhang R, Guo X, Tamura H, Ambe D, Lee JS, Okuno A, Yoshinari H, Setou T, Komatsu K (2009) Water mass variability in the western North Pacific detected in a 15-year eddy resolving ocean reanalysis. J Oceanogr 65:737–756CrossRefGoogle Scholar
  74. Mizuno K, White WB (1983) Annual and interannual variability in the Kuroshio Current System. J Phys Oceanogr 13:1847–1867CrossRefGoogle Scholar
  75. Mori K, Uehara K, Kameda T, Kakehi S (2008) Direct measurements of dissipation rate of turbulent kinetic energy of North Pacific subtropical mode water. Geophys Res Lett 35:L05601. doi: 10.1029/2007GL032867 CrossRefGoogle Scholar
  76. Nakamura H (1996) A pycnostad on the bottom of the ventilated portion in the central subtropical North Pacific: Its distribution and formation. J Oceanogr 52:171–188CrossRefGoogle Scholar
  77. Nishikawa S, Kubokawa A (2007) Mixed layer depth front and subduction of low potential vorticity water in an idealized ocean GCM. J Oceanogr 63:125–134CrossRefGoogle Scholar
  78. Nishikawa S, Tsujino H, Sakamoto K, Nakano H (2010) Effects of mesoscale eddies on subduction and distribution of subtropical mode water in an eddy-resolving OGCM of the western North Pacific. J Phys Oceanogr 40:1748–1765CrossRefGoogle Scholar
  79. Nitta T, Yamada S (1989) Recent warming of tropical sea surface temperature and its relationship to the Northern Hemisphere circulation. J Meteorol Soc Jpn 67:375–382Google Scholar
  80. Nonaka M, Xie SP (2000) Propagation of North Pacific interdecadal subsurface temperature anomalies in an ocean GCM. Geophys Res Lett 27:3747–3750CrossRefGoogle Scholar
  81. Nonaka M, Nakamura H, Tanimoto Y, Kagimoto T, Sasaki H (2006) Decadal variability in the Kuroshio-Oyashio Extension simulated in an eddy-resolving OGCM. J Clim 19:1970–1989CrossRefGoogle Scholar
  82. Nonaka M, Xie SP, Sasaki H (2011) Interannual variations in low potential vorticity water and the subtropical countercurrent in an eddy-resolving OGCM. J Oceanogr (this issue)Google Scholar
  83. Ohno Y, Kobayashi T, Iwasaka N, Suga T (2004) The mixed layer depth in the North Pacific as detected by the Argo floats. Geophys Res Lett 31:L11306. doi: 10.1029/2004GL019576 CrossRefGoogle Scholar
  84. Ohno Y, Iwasaka N, Kobashi F, Sato Y (2009) Mixed layer depth climatology of the North Pacific based on Argo observations. J Oceanogr 65:1–16CrossRefGoogle Scholar
  85. Oka E (2009) Seasonal and interannual variation of North Pacific subtropical mode water in 2003–2006. J Oceanogr 65:151–164CrossRefGoogle Scholar
  86. Oka E, Suga T (2003) Formation region of North Pacific subtropical mode water in the late winter of 2003. Geophys Res Lett 30:2205. doi: 10.1029/2003GL018581 CrossRefGoogle Scholar
  87. Oka E, Suga T (2005) Differential formation and circulation of North Pacific central mode water. J Phys Oceanogr 35:1997–2011CrossRefGoogle Scholar
  88. Oka E, Talley LD, Suga T (2007) Temporal variability of winter mixed layer in the mid- to high-latitude North Pacific. J Oceanogr 63:293–307CrossRefGoogle Scholar
  89. Oka E, Toyama K, Suga T (2009) Subduction of North Pacific central mode water associated with subsurface mesoscale eddy. Geophys Res Lett 36:L08607. doi: 10.1029/2009GL037540 CrossRefGoogle Scholar
  90. Oka E, Kouketsu S, Toyama K, Uehara K, Kobayashi T, Hosoda S, Suga T (2011a) Formation and subduction of central mode water based on profiling float data, 2003–08. J Phys Oceanogr 41:113–129CrossRefGoogle Scholar
  91. Oka E, Suga T, Sukigara C, Toyama K, Shimada K, Yoshida J (2011b) “Eddy-resolving” observation of the North Pacific subtropical mode water. J Phys Oceanogr 41:666–681CrossRefGoogle Scholar
  92. Ono T, Midorikawa T, Watanabe YW, Tadokoro K, Saino T (2001) Temporal increases of phosphate and apparent oxygen utilization in the subsurface waters of western subarctic Pacific from 1968 to 1998. Geophys Res Lett 28:3285–3288CrossRefGoogle Scholar
  93. Palter JB, Lozier MS, Barber RT (2005) The effect of advection on the nutrient reservoir in the North Atlantic subtropical gyre. Nature 437:687–692CrossRefGoogle Scholar
  94. Pan A, Liu Q (2005) Mesoscale eddy effects on the wintertime vertical mixing in the formation region of the North Pacific subtropical mode water. Chin Sci Bull 50:1949–1956CrossRefGoogle Scholar
  95. Qiu B (1999) Seasonal eddy field modulation of the North Pacific Subtropical Countercurrent: TOPEX/POSEIDON observations and theory. J Phys Oceanogr 29:2471–2468Google Scholar
  96. Qiu B (2002) The Kuroshio Extension system: its large-scale variability and role in the midlatitude ocean–atmosphere interaction. J Oceanogr 58:57–75CrossRefGoogle Scholar
  97. Qiu B (2003) Kuroshio Extension variability and forcing of the Pacific decadal oscillations: responses and potential feedback. J Phys Oceanogr 33:2465–2482CrossRefGoogle Scholar
  98. Qiu B, Chen S (2005) Variability of the Kuroshio Extension jet, recirculation gyre and mesoscale eddies on decadal timescales. J Phys Oceanogr 35:2090–2103CrossRefGoogle Scholar
  99. Qiu B, Chen S (2006) Decadal variability in the formation of the North Pacific subtropical mode water: oceanic versus atmospheric control. J Phys Oceanogr 36:1365–1380CrossRefGoogle Scholar
  100. Qiu B, Chen S (2010a) Interannual-to-decadal variability in the bifurcation of the North Equatorial Current off the Philippines. J Phys Oceanogr 40:2525–2538CrossRefGoogle Scholar
  101. Qiu B, Chen S (2010b) Eddy-mean flow interaction in the decadally modulating Kuroshio Extension system. Deep Sea Res II 57:1098–1110CrossRefGoogle Scholar
  102. Qiu B, Chen S (2011) Effect of decadal Kuroshio Extension jet and eddy variability on the modification of North Pacific intermediate water. J Phys Oceanogr 41:503–515CrossRefGoogle Scholar
  103. Qiu B, Huang RX (1995) Ventilation of the North Atlantic and North Pacific: subduction versus obduction. J Phys Oceanogr 25:2374–2390CrossRefGoogle Scholar
  104. Qiu B, Chen S, Hacker P (2004) Synoptic-scale air-sea flux forcing in the western North Pacific: observations and their impact on SST and the mixed layer. J Phys Oceanogr 34:2148–2159CrossRefGoogle Scholar
  105. Qiu B, Hacker P, Chen S, Donohue KA, Watts DR, Mitsudera H, Hogg NG, Jayne SR (2006) Observations of the subtropical mode water evolution from the Kuroshio Extension System Study. J Phys Oceanogr 36:457–473CrossRefGoogle Scholar
  106. Qiu B, Chen S, Hacker P (2007) Effect of mesoscale eddies on subtropical mode water variability from the Kuroshio Extension System Study (KESS). J Phys Oceanogr 37:982–1000CrossRefGoogle Scholar
  107. Qu T, Chen J (2009) A North Pacific decadal variability in subduction rate. Geophys Res Lett 36:L22602. doi: 10.1029/2009GL040914 CrossRefGoogle Scholar
  108. Qu T, Xie SP, Mitsudera H, Ishida A (2002) Subduction of the North Pacific mode waters in a global high-resolution GCM. J Phys Oceanogr 32:746–763CrossRefGoogle Scholar
  109. Rainville L, Jayne SR, McClean JL, Maltrud ME (2007) Formation of subtropical mode water in a high-resolution ocean simulation of the Kuroshio Extension region. Ocean Modell 17:338–356CrossRefGoogle Scholar
  110. Roden GI (1970) Aspects of the mid-Pacific transition zone. J Geophys Res 75:1097–1109CrossRefGoogle Scholar
  111. Roden GI (1972) Temperature and salinity fronts at the boundaries of the subarctic-subtropical transition zone in the western Pacific. J Geophys Res 77:7175–7187CrossRefGoogle Scholar
  112. Roemmich D, Boebel O, Desaubies Y, Freeland H, King B, LeTraon PY, Molinari R, Owens WB, Riser S, Send U, Takeuchi K, Wijffels S (2001) Argo: the global array of profiling floats. In: Koblinsky CJ, Smith NR (eds) Observing the oceans in the 21st century. GODAE Project Office, Bureau of Meteorology, Melbourne, pp 248–258Google Scholar
  113. Roemmich D, Johnson GC, Riser S, Davis R, Gilson J, Owens WB, Garzoli SL, Schmid C, Ignaszewski M (2009) Argo: the challenge of continuing 10 years of progress. Oceanography 22:46–55CrossRefGoogle Scholar
  114. Saito H, Suga T, Hanawa K, Watanabe T (2007) New type of pycnostad in the western subtropical-subarctic transition region of the North Pacific: transition region mode water. J Oceanogr 63:589–600CrossRefGoogle Scholar
  115. Saito H, Suga T, Hanawa K, Shikama N (2011) The transition region mode water of the North Pacific and its rapid modification. J Phys Oceanogr (in press)Google Scholar
  116. Sasaki YN, Schneider N, Maximenko N, Lebedev K (2010) Observational evidence for propagation of decadal spiciness anomalies in the North Pacific. Geophys Res Lett 37:L07708. doi: 10.1029/2010GL042716 CrossRefGoogle Scholar
  117. Sasaki H, Xie SP, Taguchi B, Nonaka M, Hosoda S, Masumoto Y (2011) Interannual variations of the Hawaiian Lee Countercurrent induced by low potential vorticity water ventilation in the subsurface. J Oceanogr (this issue)Google Scholar
  118. Schneider N, Miller AJ, Alexander MA, Deser C (1999) Subduction of decadal North Pacific temperature anomalies: observations and dynamics. J Phys Oceanogr 29:1056–1070CrossRefGoogle Scholar
  119. Shimada K, Nomoto M, Yoshida J (2007) Distribution of the density ratio in the North Pacific. La Mer 45:149–158Google Scholar
  120. Sprintall J, Roemmich D (1999) Characterizing the structure of the surface layer in the Pacific Ocean. J Geophys Res 104:23297–23311CrossRefGoogle Scholar
  121. Stommel HM (1979) Determination of water mass properties of water pumped down from Ekman layer to the geostrophic flow below. Proc Natl Acad Sci USA 76:3051–3055CrossRefGoogle Scholar
  122. Stommel H, Schott F (1977) The beta spiral and the determination of the absolute velocity field from hydrographic station data. Deep Sea Res 24:325–329CrossRefGoogle Scholar
  123. Suga T, Hanawa K (1990) The mixed layer climatology in the northwestern part of the North Pacific subtropical gyre and the formation area of subtropical mode water. J Mar Res 48:543–566Google Scholar
  124. Suga T, Hanawa K (1995a) The subtropical mode water circulation in the North Pacific. J Phys Oceanogr 25:958–970CrossRefGoogle Scholar
  125. Suga T, Hanawa K (1995b) Interannual variations of North Pacific subtropical mode water in the 137°E section. J Phys Oceanogr 25:1012–1017CrossRefGoogle Scholar
  126. Suga T, Hanawa K (1995c) Subtropical mode water south of Honshu, Japan in the spring of 1988 and 1989. J Oceanogr 51:1–19CrossRefGoogle Scholar
  127. Suga T, Hanawa K, Toba Y (1989) Subtropical mode water in the 137°E section. J Phys Oceanogr 19:1605–1618CrossRefGoogle Scholar
  128. Suga T, Takei Y, Hanawa K (1997) Thermostad distribution in the North Pacific subtropical gyre: the central mode water and the subtropical mode water. J Phys Oceanogr 27:140–152CrossRefGoogle Scholar
  129. Suga T, Kato A, Hanawa K (2000) North Pacific tropical water: its climatology and temporal changes associated with the climate regime shift in the 1970s. Prog Oceanogr 47:223–256CrossRefGoogle Scholar
  130. Suga T, Motoki K, Hanawa K (2003) Subsurface water masses in the central North Pacific transition region: the repeat section along the 180° meridian. J Oceanogr 59:435–444CrossRefGoogle Scholar
  131. Suga T, Motoki K, Aoki Y, Macdonald AM (2004) The North Pacific climatology of winter mixed layer and mode waters. J Phys Oceanogr 34:3–22CrossRefGoogle Scholar
  132. Suga T, Aoki Y, Saito H, Hanawa K (2008) Ventilation of the North Pacific subtropical pycnocline and mode water formation. Prog Oceanogr 77:285–297CrossRefGoogle Scholar
  133. Suga T, Sato K, Nonaka M, Hosoda S, Ueno H, Shikama N, Kobayashi T, Iwasaka N, Oka E (2011) A revisit to causes of the North Pacific central mode water property changes associated with regime shifts. In: Hall J, Harrison DE, Stammer D (eds) Proceedings of the OceanObs’09: sustained ocean observations and information for society (Annex), 21–25 September 2009. ESA Publication WPP-306, Venice, Italy (in press)Google Scholar
  134. Sugimoto S, Hanawa K (2005a) Remote reemergence areas of winter sea surface temperature anomalies in the North Pacific. Geophys Res Lett 32:L01606. doi: 10.1029/2004GL021410 CrossRefGoogle Scholar
  135. Sugimoto S, Hanawa K (2005b) Why does reemergence of winter sea surface temperature anomalies not occur in eastern mode water areas? Geophys Res Lett 32:L15608. doi: 10.1029/2005GL022968 CrossRefGoogle Scholar
  136. Sugimoto S, Hanawa K (2007) Further evidence for nonreemergence of winter SST anomalies in the North Pacific eastern subtropical mode water area. J Oceanogr 63:625–635CrossRefGoogle Scholar
  137. Sugimoto S, Hanawa K (2010) Impact of Aleutian Low activity on the STMW formation in the Kuroshio recirculation gyre region. Geophys Res Lett 37:L03606. doi: 10.1029/2009GL041795 CrossRefGoogle Scholar
  138. Sukigara C, Suga T, Saino T, Toyama K, Yanagimoto D, Hanawa K, Shikama N (2011) Biogeochemical evidence of large diapycnal diffusivity associated with the subtropical mode water of the North Pacific. J Oceanogr 67:77–85CrossRefGoogle Scholar
  139. Taguchi B, Xie SP, Schneider N, Nonaka M, Sasaki H, Sasai Y (2007) Decadal variability of the Kuroshio Extension: observations and an eddy-resolving model hindcast. J Clim 20:2357–2377CrossRefGoogle Scholar
  140. Takikawa T, Ichikawa H, Ichikawa K, Kawae S (2005) Extraordinary subsurface mesoscale eddy detected in the southeast of Okinawa in February 2002. Geophys Res Lett 32:L17602. doi: 10.1029/2005GL023842 CrossRefGoogle Scholar
  141. Talley LD (1988) Potential vorticity distribution in the North Pacific. J Phys Oceanogr 18:89–106CrossRefGoogle Scholar
  142. Taneda T, Suga T, Hanawa K (2000) Subtropical mode water variation in the southwestern part of the North Pacific subtropical gyre. J Geophys Res 105:19591–19598CrossRefGoogle Scholar
  143. Tanimoto Y, Iwasaka N, Hanawa K, Toba Y (1993) Characteristic variations of sea surface temperature with multiple time scales in the North Pacific. J Clim 6:1153–1160CrossRefGoogle Scholar
  144. Toba Y, Kawamura H, Hanawa K, Otobe H, Taira K (1991) Outbreak of warm water from the Kuroshio south of Japan—a combined analysis of satellite and OMLET oceanographic data. J Oceanogr Soc Jpn 47:297–303CrossRefGoogle Scholar
  145. Tomita H, Kako S, Cronin MF, Kubota M (2010) Preconditioning of the wintertime mixed layer at the Kuroshio Extension Observatory. J Geophys Res 115:C12053. doi: 10.1029/2010JC006373 CrossRefGoogle Scholar
  146. Tomosada A (1986) Generation and decay of Kuroshio warm-core rings. Deep Sea Res 33:1475–1486CrossRefGoogle Scholar
  147. Toyama K, Suga T (2010) Vertical structure of North Pacific mode waters. Deep Sea Res II 57:1152–1160CrossRefGoogle Scholar
  148. Toyama K, Suga T (2011) Roles of mode waters in formation and maintenance of central water in the North Pacific. J Oceanogr (this issue)Google Scholar
  149. Toyoda T, Awaji T, Ishikawa Y, Nakamura T (2004) Preconditioning of winter mixed layer in the formation of North Pacific eastern subtropical mode water. Geophys Res Lett 31:L17206. doi: 10.1029/2004GL020677 CrossRefGoogle Scholar
  150. Toyoda T, Awaji T, Masuda S, Sugiura N, Igarashi H, Mochizuki T, Ishikawa Y (2011) Interannual variability of North Pacific eastern subtropical mode water formation in the 1990s derived from a 4-dimensional variational ocean data assimilation experiment. Dyn Atmos Oceans 51:1–25CrossRefGoogle Scholar
  151. Trenberth KE (1990) Recent observed interdecadal climate changes in the Northern Hemisphere. Bull Am Meteorol Soc 71:988–993CrossRefGoogle Scholar
  152. Trenberth KE, Hurrell JW (1994) Decadal atmosphereocean variations in the Pacific. Clim Dyn 9:303–319CrossRefGoogle Scholar
  153. Tsujino H, Yasuda T (2004) Formation and circulation of mode waters of the North Pacific in a high-resolution GCM. J Phys Oceanogr 34:399–415CrossRefGoogle Scholar
  154. Uda M (1963) Oceanography of the subarctic Pacific Ocean. J Fish Res Board Can 20:119–179CrossRefGoogle Scholar
  155. Uda M, Hasunuma K (1969) The eastward subtropical countercurrent in the western North Pacific Ocean. J Oceanogr Soc Jpn 25:201–210Google Scholar
  156. Uehara H, Suga T, Hanawa K, Shikama N (2003) A role of eddies in formation and transport of North Pacific subtropical mode water. Geophys Res Lett 30:1705. doi: 10.1029/2003GL017542 CrossRefGoogle Scholar
  157. Watanabe YW, Ono T, Shimamoto A, Sugimoto T, Wakita M, Watanabe S (2001) Probability of a reduction in the formation rate of the subsurface water in the North Pacific during the 1980s and 1990s. Geophys Res Lett 28:3289–3292CrossRefGoogle Scholar
  158. Williams RG (1989) The influence of air–sea interaction on the ventilated thermocline. J Phys Oceanogr 19:1255–1267CrossRefGoogle Scholar
  159. Williams RG (1991) The role of the mixed layer in setting the potential vorticity of the main thermocline. J Phys Oceanogr 21:1803–1814CrossRefGoogle Scholar
  160. Xie SP, Kunitani T, Kubokawa A, Nonaka M, Hosoda S (2000) Interdecadal thermocline variability in the North Pacific for 1958–97: a GCM simulation. J Phys Oceanogr 30:2798–2813CrossRefGoogle Scholar
  161. Xie SP, Deser C, Vecchi GA, Ma J, Teng H, Wittenberg AT (2010) Global warming pattern formation: sea surface temperature and rainfall. J Clim 23:966–986CrossRefGoogle Scholar
  162. Xie SP, Xu LX, Liu Q, Kobashi F (2011) Dynamical role of mode-water ventilation in decadal variability in the central subtropical gyre of the North Pacific. J Clim 24:1212–1225CrossRefGoogle Scholar
  163. Xu LX, Xie SP, Liu Q, Kobashi F (2011) Response of the North Pacific Subtropical Countercurrent and its variability to global warming. J Oceanogr (this issue)Google Scholar
  164. Yamanaka G, Ishizaki H, Hirabara M, Ishikawa I (2008) Decadal variability of the Subtropical Front of the western North Pacific in an eddy-resolving ocean general circulation model. J Geophys Res. 113:C12027. doi: 10.1029/2008JC005002
  165. Yasuda I (2003) Hydrographic structure and variability of the Kuroshio-Oyashio transition area. J Oceanogr 59:389–402CrossRefGoogle Scholar
  166. Yasuda T, Hanawa K (1997) Decadal changes in the mode waters in the midlatitude North Pacific. J Phys Oceanogr 27:858–870CrossRefGoogle Scholar
  167. Yasuda T, Hanawa K (1999) Composite analysis of North Pacific subtropical mode water properties with respect to the strength of the wintertime East Asian monsoon. J Oceanogr 55:531–541CrossRefGoogle Scholar
  168. Yasuda T, Kitamura Y (2003) Long-term variability of North Pacific subtropical mode water in response to spin-up of the subtropical gyre. J Oceanogr 59:279–290CrossRefGoogle Scholar
  169. Yasuda I, Okuda K, Hirai M (1992) Evolution of a Kuroshio warm-core ring—variability of the hydrographic structure. Deep Sea Res 39:S131–S161CrossRefGoogle Scholar
  170. Yoshida S (1964) A note on the variations of the Kuroshio during recent years. Bull Jpn Soc Fish Oceanogr 5:66–69 (in Japanese)Google Scholar
  171. Yoshida T, Hoshimoto M (2006) Heat content change in the surface isothermal layer of a warm core ring in the sea east of Japan. J Oceanogr 62:283–287CrossRefGoogle Scholar
  172. Yuan X, Talley LD (1996) The subarctic frontal zone in the North Pacific: characteristics of frontal structure from climatological data and synoptic surveys. J Geophys Res 101:16491–16508CrossRefGoogle Scholar
  173. Zhang Y (1996) An observational study of atmosphere–ocean interaction in the northern oceans on interannual and interdecadal time-scales. Ph.D. dissertation, University of Washington, Seattle, WAGoogle Scholar
  174. Zhang RX, Hanawa K (1993) Features of the water-mass front in the northwestern North Pacific. J Geophys Res 98:967–975CrossRefGoogle Scholar

Copyright information

© The Oceanographic Society of Japan and Springer 2011

Authors and Affiliations

  1. 1.Atmosphere and Ocean Research InstituteThe University of TokyoKashiwaJapan
  2. 2.Department of OceanographyUniversity of Hawaii at ManoaHonoluluUSA

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