Outflow of the intermediate Oyashio water from Sagami Bay to the Shikoku Basin

• Published in: Journal of oceanography Vol. 58; no. 4; pp. 531 - 537
• Main Authors: SEKINE, Yoshihiko, UCHIYAMA, Keita
• Format: Journal Article
• Language: English
• Published: Tokyo Springer 01.08.2002; Dordrecht Terra; Springer Nature B.V
• Subjects: Coastal oceanography, estuaries. Regional oceanography; Earth, ocean, space; Exact sciences and technology; External geophysics; Marine; Physics of the oceans; Saline water; Oyashio Current; Sagami Bay; Asia; Shikoku; Japan; Kuroshio; Pacific Ocean; North Pacific; INW, Japan, Honshu, Kanagawa Prefect., Sagami Bay; INW, Pacific, Oyashio Current; INW, Japan Sea, Oyashio Water; INW, Pacific, Shikoku Basin; INW, Pacific, Kuroshio Current; INW, Japan, Honshu, Chiba Prefect., Boso Peninsula; INW, Japan, Honshu, Shizuoka Prefect., Izu Peninsula; Potential density; Intermediate water; Water flow
• ISSN: 0916-8370; 1573-868X
• DOI: 10.1023/a:1021273509015

Since the Intermediate Oyashio Water (IOW) gradually accumulates in Sagami Bay, it can reasonably be supposed that the IOW also flows out from Sagami Bay, even though it may be altered by mixing with other waters. We have occasionally observed a water less than 34.2 psu with a potential density of 26.8 at the southeastern area off Izu Peninsula in July 1993 by the training vessel Seisui-maru of Mie University. Observational data supplied by the Japan Meteorological Agency and the Kanagawa Prefectural Fisheries Experimental Station show that the IOW of less than 34.1 psu was observed at northern stations of the line PT (KJ) off the Boso Peninsula and to the east of Oshima in the late spring 1993. Based upon these observations, it is concluded that the IOW flows out from Sagami Bay into the Shikoku Basin along southeastern area off the Izu Peninsula. The less saline water (<34.2 psu) was also observed to the west of Miyake-jima during the same cruise, and the westward intrusion of IOW from south of the Boso Peninsula to the Shikoku Basin through the gate area of the Kuroshio path over the Izu Ridge was detected. This event indicated that the IOW branched south of the Boso Peninsula and flowed into Sagami Bay and/or into the gate area over the Izu Ridge. The southward intrusion of IOW into the south of the Boso Peninsula is discussed in relation to the latitudinal location of the main axes of the Kuroshio and the Oyashio.