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Journal of Oceanography

, Volume 65, Issue 1, pp 1–16 | Cite as

Mixed layer depth climatology of the North Pacific based on Argo observations

  • Yuko Ohno
  • Naoto Iwasaka
  • Fumiaki Kobashi
  • Yoshiko Sato
Original Articles

Abstract

A monthly mean climatology of the mixed layer depth (MLD) in the North Pacific has been produced by using Argo observations. The optimum method and parameter for evaluating the MLD from the Argo data are statistically determined. The MLD and its properties from each density profile were calculated with the method and parameter. The monthly mean climatology of the MLD is computed on a 2° × 2° grid with more than 30 profiles for each grid. Two bands of deep mixed layer with more than 200 m depth are found to the north and south of the Kuroshio Extension in the winter climatology, which cannot be reproduced in some previous climatologies. Early shoaling of the winter mixed layer between 20–30°N, which has been pointed out by previous studies, is also well recognized. A notable feature suggested by our climatology is that the deepest mixed layer tends to occur about one month before the mixed layer density peaks in the middle latitudes, especially in the western region, while they tend to coincide with each other in higher latitudes.

Keywords

Mixed layer depth Argo data mixed layer climatology 

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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Yuko Ohno
    • 1
    • 2
  • Naoto Iwasaka
    • 1
    • 3
  • Fumiaki Kobashi
    • 1
  • Yoshiko Sato
    • 1
    • 4
  1. 1.Tokyo University of Marine Science and TechnologyKoto-ku, TokyoJapan
  2. 2.Kisarazu National College of TechnologyChibaJapan
  3. 3.Institute of Observational Research for Global ChangeJAMSTECKanagawaJapan
  4. 4.Shinko Co. Ltd.TokyoJapan

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