We thank Fritz Schott and Yukio Masumoto for stimulating discussions and Weiqing Han for providing us the source code of the linear, continuously stratified model. This research was supported by the Japan Agency for Marine–Earth Science and Technology (JAMSTEC) through its sponsorship of the International Pacific Research Center (IPRC). Toru Miyama was supported by funds from the MEXT RR2002 project. Debasis Sengupta acknowledges support from the Department of Ocean Development, New Delhi, India.
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