Decadal seesaw of the Central and Subtropical Mode Water formation associated with the Kuroshio Extension variability
Available Argo profiling float data from 2002 to 2011 were analyzed to examine the effect of the Kuroshio Extension (KE) current system variability on the formation of the Central Mode Water. Just north of the upstream portion of the KE at 140–152°E, formation of a lighter variety of the Central Mode Water in winter was active during the unstable period of the upstream KE in 2006–2009 and was reduced when the upstream KE was in the stable period of 2002–2005 and 2010–2011. This decadal formation variability is out of phase with that of the Subtropical Mode Water just south of the KE.
KeywordsDecadal variability North Pacific Mode waters Kuroshio Extension Mesoscale eddies
The authors thank Tsuyoshi Ohira for help in preparing the Argo float data and two anonymous reviewers for helpful comments on the manuscript. The Argo float data used in this study were collected and made freely available by the International Argo Project and the national programs that contribute to it (http://www.argo.ucsd.edu, http://argo.jcommops.org). This study was motivated by discussions between EO and BQ in summer 2010 when EO visited the University of Hawaii at Manoa for 1 month under the Overseas Internship Program for Outstanding Young Earth and Planetary Researchers provided by the Department of Earth and Planetary Science, the University of Tokyo. EO, KU, and TS are supported by the Japan Society for Promotion of Science (KAKENHI, Grant-in-Aid for Scientific Research (B), no. 21340133) and the Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT; Grant-in-Aid for Scientific Research on Innovative Areas under grant no. 22106007). BQ is supported by NSF through Grant OCE-0220680 and NASA through contract 1207881.
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