Geo-Marine Letters

, Volume 36, Issue 5, pp 353–360 | Cite as

Intensification of North Pacific intermediate water ventilation during the Younger Dryas

  • Ken’ichi OhkushiEmail author
  • Naoki Hara
  • Minoru Ikehara
  • Masao Uchida
  • Naokazu Ahagon


Modern North Pacific intermediate water (NPIW) is formed in the mixed water region where the Oyashio and Kuroshio currents meet. The source for cooling and freshening of NPIW is intermediate water in the Okhotsk Sea. The Okhotsk intermediate water outflows to the open Pacific, forming the Oyashio intermediate water by mixing with the subarctic gyre water. In the Oyashio region, the intermediate water originating from the Okhotsk Sea flows mainly at depths shallower than 500 m. On the other hand, ventilation of intermediate water in the subarctic Pacific during the deglaciation remains a topic of debate. In this study, foraminiferal δ18O and δ13C signatures were determined in a dated sediment core collected at 777 m water depth to evaluate the intensity and depth distribution of the source of NPIW since the last deglaciation in the Oyashio region. Benthic foraminiferal δ18O increased by 0.3–0.4‰ from the end of the Bølling/Ållerød warm episode to the Younger Dryas cold episode, suggesting intermediate water cooling. Consistent with this trend, benthic δ13C values point to decreased nutrient contents during the cold event. Conversely, benthic δ18O signatures from a nearby core site at a water depth of 1,366 m did not show such cooling. These results suggest that cold intermediate water originating from the north was actively ventilated at depths of at least 700–800 m, and possibly even 1,200 m during the Younger Dryas, implying that NPIW ventilation was thicker and deeper than under modern conditions.


Intermediate Water North Pacific Intermediate Water Oyashio Water Younger Dryas Oyashio Region 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We thank Isao Motoyama, Ken Ikehara, Michiyo Kobayashi, Takashi Setoguchi, Naoto Danzuka, Yutaro Asano, Hiroyuki Yoshii, Yasuyuki Tatsuta, and Katsunori Kimoto for sample preparation and isotope analyses. We also thank the captain, crew, and scientific staff of the MR04-06 cruise aboard the R/V Mirai. This study was supported by JSPS KAKENHI grant number 26400504, under the cooperative research program of the Center for Advanced Marine Core Research (CMCR), Kochi University (07A021, 08A007, 08B006, 09B032, 14A008, 14B006). The manuscript benefitted from independent review comments as well as additional suggestions from the journal editors.

Compliance with ethical standards

Conflict of interest

The authors declare that there is no conflict of interest with third parties.

Supplementary material

367_2016_450_MOESM1_ESM.pdf (55 kb)
ESM 1 (PDF 55 kb)
367_2016_450_MOESM2_ESM.pdf (77 kb)
ESM 2 (PDF 77 kb)


  1. Ahagon N, Ohkushi K, Uchida M, Mishima M (2003) Mid-depth circulation in the northwest Pacific during the last deglaciation: evidence from foraminiferal radiocarbon ages. Geophys Res Lett 30:2097. doi: 10.1029/2003GL018287 CrossRefGoogle Scholar
  2. Behl RJ, Kennett JP (1996) Brief interstadial events in the Santa Barbara basin, NE Pacific, during the past 60 kyr. Nature 379:243–246. doi: 10.1038/379243a0 CrossRefGoogle Scholar
  3. Blunier T, Brook EJ (2001) Timing of millennial-scale climate change in Antarctica and Greenland during the last glacial period. Science 291:109–112. doi: 10.1126/science.291.5501.109 CrossRefGoogle Scholar
  4. Freeman E, Skinner LC, Tisserand A, Dokken T, Timmermann A, Menviel L, Friedrich T (2015) An Atlantic–Pacific ventilation seesaw across the last deglaciation. Earth Planet Sci Lett 424:237–244. doi: 10.1016/j.epsl.2015.05.032 CrossRefGoogle Scholar
  5. Friedman I, O’Neil JR (1977) Compilation of stable isotope fractionation factors of geochemical interest. In: Fleischer M (ed) Data of geochemistry. US Government Printing Office, Washington, DC, pp 1–12Google Scholar
  6. Grootes PM, Stuiver M, White JWC, Johnsen SJ, Jouzel J (1993) Comparison of oxygen isotope records from the GISP2 and GRIP Greenland ice cores. Nature 366:552–554. doi: 10.1038/366552a0 CrossRefGoogle Scholar
  7. Hendy IL, Kennett JP (2003) Tropical forcing of North Pacific intermediate water distribution during Late Quaternary rapid climate change. Quat Sci Rev 22:673–689. doi: 10.1016/S0277-3791(02)00186-5 CrossRefGoogle Scholar
  8. Hoshiba M, Ahagon N, Ohkushi K, Uchida M, Motoyama I, Nishimura A (2006) Foraminiferal oxygen and carbon isotopes during the last 34 kyr off northern Japan, northwestern Pacific. Mar Micropaleontol 61:196–208. doi: 10.1016/j.marmicro.2006.07.001 CrossRefGoogle Scholar
  9. Ikehara K, Ohkushi K, Shibahara A, Hoshiba M (2006) Change of bottom water conditions at intermediate depths of the Oyashio region, NW Pacific over the past 20,000 yrs. Global Planet Change 53:78–91. doi: 10.1016/j.gloplacha.2006.01.011 CrossRefGoogle Scholar
  10. Ishizaki Y, Ohkushi K, Ito T, Kawahata H (2009) Abrupt changes of intermediate-water oxygen in the northwestern Pacific during the last 27 kyr. Geo-Mar Lett 29:125–131. doi: 10.1007/s00367-008-0128-0 CrossRefGoogle Scholar
  11. Jaccard SL, Galbraith ED (2013) Direct ventilation of the North Pacific did not reach the deep ocean during the last deglaciation. Geophys Res Lett 40:199–203. doi: 10.1029/2012GL054118 CrossRefGoogle Scholar
  12. Keigwin LD (1998) Glacial-age hydrography of the far northwest Pacific Ocean. Paleoceanography 13:323–339. doi: 10.1029/98PA00874 CrossRefGoogle Scholar
  13. Kennett JP, Ingram BL (1995) A 20,000-year record of ocean circulation and climate change from the Santa Barbara Basin. Nature 377:510–514. doi: 10.1038/377510a0 CrossRefGoogle Scholar
  14. Kennett JP, Cannariato KG, Hendy IL, Behl RJ (2000) Carbon isotopic evidence for methane hydrate instability during Quaternary interstadials. Science 288:128–133. doi: 10.1126/science.288.5463.128 CrossRefGoogle Scholar
  15. Ma W, Tian J (2014) Modeling the contribution of dissolved organic carbon to carbon sequestration during the last glacial maximum. Geo-Mar Lett 34:471–482. doi: 10.1007/s00367-014-0378-y CrossRefGoogle Scholar
  16. Max L, Lembke-Jene L, Riethdorf JR, Tiedemann R, Nürnberg D, Kühn H, Mackensen A (2014) Pulses of enhanced North Pacific Intermediate Water ventilation from the Okhotsk Sea and Bering Sea during the last deglaciation. Clim Past 10:591–605. doi: 10.5194/cp-10-591-2014 CrossRefGoogle Scholar
  17. McCorkle DC, Keigwin LD (1994) Depth profiles of δ13C in bottom water and core top C. wuellerstorfi on the Ontong Java Plateau and Emperor Seamounts. Paleoceanography 9:197–208. doi: 10.1029/93PA03271 CrossRefGoogle Scholar
  18. Méheust M, Stein R, Fahl K, Max L, Riethdorf J-R (2016) High-resolution IP25-based reconstruction of sea-ice variability in the western North Pacific and Bering Sea during the past 18,000 years. Geo-Mar Lett 36:101–111. doi: 10.1007/s00367-015-0432-4 CrossRefGoogle Scholar
  19. Mikolajewicz U, Crowley TJ, Schiller A, Voss R (1997) Modeling teleconnections between the North Atlantic and North Pacific during the Younger Dryas. Nature 387:384–387. doi: 10.1038/387384a0 CrossRefGoogle Scholar
  20. Ohkushi K, Uchida M, Aoki K, Yoneda M, Ikehara K, Minoshima K, Kawahata H, Tada R, Murayama M, Shibata Y (2007) Radiocarbon marine reservoir ages in the northwestern Pacific off Hokkaido Island, Japan, during the last deglacial period. Radiocarbon 49:963–968CrossRefGoogle Scholar
  21. Okazaki Y, Timmermann A, Menviel L, Harada N, Abe-Ouchi A, Chikamoto MO, Mouchet A, Asahi H (2010) Deepwater formation in the North Pacific during the last glacial termination. Science 329:200–204. doi: 10.1126/science.1190612 CrossRefGoogle Scholar
  22. Reimer BE, Bayliss A, Beck JW, Blackwell PG, Bronk Ramsey C, Buck CE, Cheng H, Edwards RL, Friedrich M, Grootes PM, Guilderson TP, Haflidason H, Hajdas I, Hatté C, Heaton TJ, Hoffmann DL, Hogg AG, Hughen KA, Kaiser KF, Kromer B, Manning SW, Niu M, Reimer RW, Richards DA, Scott EM, Southon JR, Staff RA, Turney CSM, van der Plicht J (2013) IntCal13 and Marine13 radiocarbon age calibration curves 0–50,000 years cal BP. Radiocarbon 55:1869–1887. doi: 10.2458/azu_js_rc.55.16947 CrossRefGoogle Scholar
  23. Sagawa T, Ikehara K (2008) Intermediate water ventilation change in the subarctic Northwest Pacific during the last deglaciation. Geophys Res Lett 38, L24702. doi: 10.1029/2008GL035133 CrossRefGoogle Scholar
  24. Sagawa T, Kuroyanagi A, Irino T, Kuwae M, Kawahata H (2013) Seasonal variations in planktonic foraminiferal flux and oxygen isotopic composition in the western North Pacific: implications for paleoceanographic reconstruction. Mar Micropaleontol 100:11–20. doi: 10.1016/j.marmicro.2013.03.013 CrossRefGoogle Scholar
  25. Sagawa T, Kuwae M, Tsuruoka K, Nakamura Y, Ikehara M, Murayama M (2014) Solar forcing of centennial-scale East Asian winter monsoon variability in the mid- to late Holocene. Earth Planet Sci Lett 395:124–135. doi: 10.1016/j.epsl.2014.03.043 CrossRefGoogle Scholar
  26. Sakamoto T, Ikehara M, Aoki K, Iijima K, Kimura N, Nakatsuka T, Wakatsuchi M (2005) Ice-rafted debris (IRD)-based sea-ice expansion events during the past 100 kyrs in the Okhotsk Sea. Deep-Sea Res II 52:2275–2301. doi: 10.1016/j.dsr2.2005.08.007 CrossRefGoogle Scholar
  27. Shackleton NJ (1974) Attainment of isotopic equilibrium between ocean water and the benthonic foraminifera genus Uvigerina: isotopic changes in the ocean during the last glacial. Engl Coll Int CNRS 219:203–209Google Scholar
  28. Shcherbina AY, Talley LD, Rudnick DL (2003) Direct observations of North Pacific ventilation: brine rejection in the Okhotsk Sea. Science 302:1952–1955. doi: 10.1126/science.1088692 CrossRefGoogle Scholar
  29. Shibahara A, Ohkushi K, Kennett JP, Ikehara K (2007) Late Quaternary changes in intermediate water oxygenation and oxygen minimum zone, northern Japan: a benthic foraminiferal perspective. Paleoceanography 22, PA3213. doi: 10.1029/2005PA001234 CrossRefGoogle Scholar
  30. Shimizu Y, Yasuda I, Ito S (2001) Distribution and circulation of the coastal Oyashio intrusion. J Phys Oceanogr 31:1561–1578. doi: 10.1175/1520-0485(2001)031<1561:DACOTC>2.0.CO;2 CrossRefGoogle Scholar
  31. Stuiver M, Reimer PJ (1993) Extended 14C database and revised CALIB 3.0 14C age calibration program. In: Stuiver M, Long A, Kra RS (eds) Calibration 1993. Radiocarbon 35:215–230CrossRefGoogle Scholar
  32. Talley LD (1993) Distribution and formation of North Pacific Intermediate Water. J Phys Oceanogr 23:517–537. doi: 10.1175/1520-0485(1993)023<0517:dafonp>;2 CrossRefGoogle Scholar
  33. Uchida M, Ohkushi K, Kimoto K, Inagaki F, Ishimura T, Tsunogai U, TuZino T, Shibata Y (2008) Radiocarbon-based carbon source quantification of anomalous isotopic foraminifera in last glacial sediments in the western North Pacific. Geochem Geophys Geosyst 9, Q04N14. doi: 10.1029/2006GC001558
  34. Wang L, Li J, Zhao J, Wie H, Hu B, Dou Y, Sun Z, Zou L, Bai F (2016) Solar-, monsoon- and Kuroshio-influenced thermocline depth and sea surface salinity in the southern Okinawa Trough during the past 17,300 years. Geo-Mar Lett 36. doi: 10.1007/s00367-016-0448-4
  35. Warren BA (1983) Why is no deep water formed in the North Pacific? J Mar Res 41:327–347CrossRefGoogle Scholar
  36. Yamamoto M, Tanaka N, Tsunogai S (2001) The Okhotsk Sea intermediate water formation deduced from oxygen isotope systematics. J Geophys Res 106:31075–31084. doi: 10.1029/2000JC000754 CrossRefGoogle Scholar
  37. Yasuda I (1997) The origin of the North Pacific Intermediate Water. J Geophys Res 102:893–909. doi: 10.1029/96JC02938 CrossRefGoogle Scholar
  38. You YZ, Suginohara N, Fukasawa M, Yoritaka H, Mizuno K, Kashino Y, Hartoyo D (2003) Transport of North Pacific Intermediate Water across Japanese WOCE sections. J Geophys Res 108:1–24. doi: 10.1029/2002JC001662 Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Ken’ichi Ohkushi
    • 1
    Email author
  • Naoki Hara
    • 1
  • Minoru Ikehara
    • 2
  • Masao Uchida
    • 3
  • Naokazu Ahagon
    • 4
  1. 1.Graduate School of Human Development and EnvironmentKobe UniversityKobeJapan
  2. 2.Center for Advanced Marine Core ResearchKochi UniversityNankokuJapan
  3. 3.National Institute for Environmental StudiesTsukubaJapan
  4. 4.Kochi Institute for Core Sample ResearchJapan Agency for Marine-Earth Science and Technology (JAMSTEC)NankokuJapan

Personalised recommendations