Composite analysis of North Pacific subtropical mode water properties with respect to the strength of the wintertime East Asian monsoon

Tamaki Yasuda, Kimio Hanawa

Research output: Contribution to journalArticlepeer-review

33 Citations (Scopus)

Abstract

The interannual variation of the thermal structure of North Pacific subtropical mode water (NPSTMW) is investigated by means of composite analysis with respect to the wintertime Monsoon Index (MOI) which can represent the strength of the wintertime East Asian monsoon. The wind stress field over the NPSTMW formation area has significant variation over the interannual (2-4 year) and the decadal (10-20 year) bands. Changes in interannual variation are well correlated with the intensity of the wintertime East Asian monsoon. By means of composite analysis, it is found that significant differences occur in the thermal structure of the NPSTMW between stronger and weaker monsoon years. That is, colder and thicker NPSTMW is formed in years with stronger monsoons. Analysis of the heat flux through the sea surface and horizontal heat divergence in the Ekman layer shows that colder and thicker NPSTMW in stronger monsoon years can be attributed to a larger amount of heat release through the sea surface in the formation area. A larger horizontal divergence of the heat transport in the upper Ekman layer is considerably responsible for this increased heat loss.

Original languageEnglish
Pages (from-to)531-541
Number of pages11
JournalJournal of Oceanography
Volume55
Issue number4
DOIs
Publication statusPublished - 1999 Aug 1

Keywords

  • Ekman heat transport
  • North Pacific subtropical mode water
  • Surface heat flux
  • Wintertime East Asian monsoon

ASJC Scopus subject areas

  • Oceanography

Fingerprint

Dive into the research topics of 'Composite analysis of North Pacific subtropical mode water properties with respect to the strength of the wintertime East Asian monsoon'. Together they form a unique fingerprint.

Cite this