Journal of Oceanography

, Volume 72, Issue 3, pp 439–451 | Cite as

Mesoscale eddy effects on temporal variability of surface chlorophyll a in the Kuroshio Extension

  • Shinya Kouketsu
  • Hitoshi Kaneko
  • Takeshi Okunishi
  • Kosei Sasaoka
  • Sachihiko Itoh
  • Ryuichiro Inoue
  • Hiromichi Ueno
Special Section: Original Article K2S1 project


We investigated the relationship between chlorophyll a (Chl-a) concentrations estimated from satellite observations and the activity of eddies in the Kuroshio Extension region. High (low) area-averaged Chl-a concentrations were frequently observed in the core of cyclonic (anticyclonic) eddies. Such relationships between Chl-a concentrations and eddy cores were not frequently observed in the southern part of the recirculation gyre, and advection of background meridional gradient of Chl-a by eddy-edge currents accounted for Chl-a spatial variability. Decadal-scale changes of Chl-a concentrations around the Kuroshio Extension were strongly affected by eddy activity and transport but not by large-scale near-surface isopycnal heaving. We also found that decadal changes of nutrient concentrations near the main stream could affect Chl-a concentrations in the southern part of the recirculation gyre via southward transport of eddies and mean flow.


Kuroshio Extension Decadal variability Mesoscale eddy Biological productivity Nutrient variability 



S. Kouketsu, S. Itoh, T. Okunishi, and H. Kaneko were supported for this study by Grant-in-Aid for Scientific Research on Innovative Areas Grant Number 12024485. We thank the reviewers and the editor for their useful comments. We extend our appreciation to the late Dr. Toshiro Saino for his encouragement to undertake this study.


  1. Boyer T, Antonov J, Baranova O, Coleman C, Garcia H, Grodsky A, Johnson D, Locarnini R, Mishonov A, O’Brien T, Paver C, Reagan J, Seidov D, Smolyar I, Zweng M (2013) World ocean database. NOAA Atlas NESDIS 72:209Google Scholar
  2. Calil PHR, Richards KJ (2010) Transient upwelling hot spots in the oligotrophic North Pacific. J Geophys Res Oceans 115(C2). doi: 10.1029/2009JC005360
  3. Chelton DB, Gaube P, Schlax MG, Early JJ, Samelson RM (2011a) The influence of nonlinear mesoscale eddies on near-surface oceanic chlorophyll. Science 334(6054):328–332. doi: 10.1126/science.1208897 CrossRefGoogle Scholar
  4. Chelton DB, Schlax MG, Samelson RM (2011b) Global observations of nonlinear mesoscale eddies. Prog Oceanogr 91(2):167–216. doi: 10.1016/j.pocean.2011.01.002 CrossRefGoogle Scholar
  5. Chiba S, Aita MN, Tadokoro K, Saino T, Sugisaki H, Nakata K (2008) From climate regime shifts to lower-trophic level phenology: synthesis of recent progress in retrospective studies of the western North Pacific. Prog Oceanogr 77:112–126. doi: 10.1016/j.pocean.2008.03.004 CrossRefGoogle Scholar
  6. Chiba S, Di Lorenzo E, Davis A, Keister JE, Taguchi B, Sasai Y, Sugisaki H (2013) Large-scale climate control of zooplankton transport and biogeography in the Kuroshio–Oyashio extension region. Geophys Res Lett 40(19):5182–5187. doi: 10.1002/grl.50999 CrossRefGoogle Scholar
  7. Gruber N, Lachkar Z, Frenzel H, Marchesiello P, Münnich M, McWilliams JC, Nagai T, Plattner GK (2011) Eddy-induced reduction of biological production in eastern boundary upwelling systems. Nat Geosci 4:787–792. doi: 10.1038/NGEO1273 CrossRefGoogle Scholar
  8. Hosoda S, Ohira T, Nakamura T (2008) A monthly mean dataset of global oceanic temperature and salinity derived from Argo float observations. JAMSTEC Rep Res Dev 8:47–59CrossRefGoogle Scholar
  9. 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
  10. 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
  11. 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
  12. Kalnay E, Kanamitsu M, Kistler R, Collins W, Deaven D, Gandin L, Iredell M, Saha S, White G, Woollen J, Zhu Y, Leetmaa A, Reynolds R, Chelliah M, Ebisuzaki W, Higgins W, Janowiak J, Mo KC, Ropelewski C, Wang J, Jenne R, Joseph D (1996) The NCEP/NCAR 40-year reanalysis project. Bull Amer Meteor Soc 77(3):437–471CrossRefGoogle Scholar
  13. Kawai H (1972) Hydrography of the Kuroshio Extension. In: Stommel H, Yoshida K (eds) Kuroshio, its physical aspects, Univ. of Tokyo Press, Tokyo, pp 235–352Google Scholar
  14. Kouketsu S, Tomita H, Oka E, Hosoda S, Kobayashi T, Sato K (2012) The role of mesoscale eddies in mixed layer deepening and mode water formation in the western North Pacific. J Oceanogr. doi: 10.1007/s10872-011-0049-9 Google Scholar
  15. Lévy M, Klein P, Treguier AM (2001) Impact of sub-mesoscale physics on production and subduction of phytoplankton in an oligotrophic regime. J Mar Res 59(4):535–565CrossRefGoogle Scholar
  16. Lin P, Chai F, Xue H, Xiu P (2014) Modulation of decadal oscillation on surface chlorophyll in the Kuroshio Extension. J Geophys Res Oceans 119:187–199. doi: 10.1002/2013JC009359 CrossRefGoogle Scholar
  17. Martin AP, Richards KJ (2001) Mechanisms for vertical nutrient transport within a North Atlantic mesoscale eddy. Deep Sea Res Part II 48:757–773. doi: 10.1016/S0967-0645(00)00096-5 CrossRefGoogle Scholar
  18. McClain CR, Feldman GC, Hooker SB (2004) An overview of the SeaWiFS project and strategies for producing a climate research quality global ocean bio-optical time series. Deep Sea Res Part II 51:5–42. doi: 10.1016/j.dsr2.2003.11.001 CrossRefGoogle Scholar
  19. McGillicuddy DJ, Robinson AR, Siegel DA, Jannasch HW, Johnson R, Dickey TD, McNeil J, Michaels AF, Knap AH (1998) Influence of mesoscale eddies on new production in the Sargasso Sea. Nature 394(6690):263–266CrossRefGoogle Scholar
  20. Oka E, Qiu B, Kouketsu S, Uehara K, Suga T (2012) Decadal seesaw of the central and subtropical mode water formation associated with the Kuroshio extension variability. J Oceanogr 68(2):355–360. doi: 10.1007/s10872-011-0098-0 CrossRefGoogle Scholar
  21. Qiu B, Chen S (2005) Variability of the Kuroshio extension jet, recirculation gyre, and mesoscale eddies on decadal time scales. J Phys Oceanogr 35(11):2090–2103CrossRefGoogle Scholar
  22. Qiu B, Chen S (2006) Decadal variability in the formation of the North Pacific subtropical mode water: oceanic versus atmospheric control. J Phus Oceanogr 36:1365–1380CrossRefGoogle Scholar
  23. 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
  24. 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(4):982–1000CrossRefGoogle Scholar
  25. Sarmiento JL, Thiele G, Key RM, Moore WS (1990) Oxygen and nitrate new production and remineralization in the North Atlantic subtropical gyre. J Geophys Res Oceans 95(C10):18303–18315. doi: 10.1029/JC095iC10p18303 CrossRefGoogle Scholar
  26. Sasai Y, Richards KJ, Ishida A, Sasaki H (2010) Effects of cyclonic mesoscale eddies on the marine ecosystem in the Kuroshio Extension region using an eddy-resolving coupled physical-biological model. Ocean Dyn 60(3):693–704. doi: 10.1007/s10236-010-0264-8 CrossRefGoogle Scholar
  27. Sasaoka K, Chiba S, Saino T (2011) Climatic forcing and phytoplankton phenology over the subarctic North Pacific from 1998 to 2006, as observed from ocean color data. Geophys Res Lett 38(15). doi: 10.1029/2011GL048299
  28. Siegel DA, Peterson P, McGillicuddy DJ, Maritorena S, Nelson NB (2011) Bio-optical footprints created by mesoscale eddies in the Sargasso Sea. Geophys Res Lett 38:L13608. doi: 10.1029/2011GL047660
  29. Suga T, Hanawa K, Toba Y (1989) Subtropical mode water in the 137E section. J Phys Oceanogr 19:1605–1618CrossRefGoogle Scholar
  30. Taguchi B, Qiu B, Nonaka M, Sasaki H, Xie S, Schneider N (2010) Decadal variability of the Kuroshio Extension: mesoscale eddies and recirculations. Ocean Dyn 60(3):673–691CrossRefGoogle Scholar
  31. Ueno H, Crawford WR, Onishi H (2010) Impact of Alaskan stream eddies on chlorophyll a distribution in the western and central subarctic North Pacific. J Oceanogr 66:319–328CrossRefGoogle Scholar

Copyright information

© The Oceanographic Society of Japan and Springer Japan 2015

Authors and Affiliations

  • Shinya Kouketsu
    • 1
  • Hitoshi Kaneko
    • 2
  • Takeshi Okunishi
    • 3
  • Kosei Sasaoka
    • 1
  • Sachihiko Itoh
    • 2
  • Ryuichiro Inoue
    • 1
  • Hiromichi Ueno
    • 4
  1. 1.Research and Development Center for Global ChangeJapan Agency for Marine-Earth Science and TechnologyYokosukaJapan
  2. 2.Center for Earth Surface System Dynamics, Atmosphere and Ocean Research InstituteThe University of TokyoKashiwaJapan
  3. 3.Tohoku National Fisheries Research InstituteFRAShiogamaJapan
  4. 4.Faculty of Fisheries ScienceHokkaido UniversitySapporoJapan

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