Journal of Oceanography

, Volume 72, Issue 3, pp 453–464 | Cite as

Physical oceanographic conditions around the S1 mooring site

  • Ryuichiro Inoue
  • Shinya Kouketsu
Special Section: Original Article K2S1 project


We describe physical oceanographic conditions around the S1 biogeochemical mooring site (30°N, 145°E) between February 2010 and July 2013. At the S1 mooring site, there is a clear seasonal variability of the mixed layer depth, wind forcing as well as horizontal kinetic energy in a near-inertial band. Interannual variability of the winter mixed layer was observed. The winter mixed layer depth was shallower in early 2010 and became deeper afterwards. Several mesoscale eddies and typhoons passed by the S1 mooring sites every year. Based on observed events, we suggest that those physical processes possibly affected biogeochemical properties around the S1 mooring site.


S1 mooring Mixed layer Eddy Typhoon Biogeochemical process 



We are indebted to the captain, crew, and other scientists on the R/V Mirai for their successful deployments of moorings and shipboard measurements. We thank Drs. Sato and Uchida at JAMSTEC for their careful calibrations of floats’ dissolved oxygen sensors, and Drs. Fujiki and Honda for providing us ADCP data, fruitful discussions and comments. Comments from three anonymous reviewers and the editor Dr. Oka greatly improved the manuscript. S. Kouketsu was supported by a Grant-in-Aid for Scientific Research on Innovative Areas (Grant Number 12024485). We express our appreciation to the late Dr. Toshiro Saino for his leadership on the K2/S1 project and encouragement.


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Copyright information

© The Oceanographic Society of Japan and Springer Japan 2015

Authors and Affiliations

  1. 1.Research and Development Center for Global ChangeJapan Agency for Marine-Earth Science and Technology (JAMSTEC)YokosukaJapan

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