PERGAMON
Continental Shelf Research 19 (1999) 1561-1575
CONTINENTAL SHELF RESEARCH
Kyucho induced by intrusion of Kuroshio water in Sagami Bay, Japan
Masaji Matsuyamaa,*, Hiroshi Ishidoyab, Shizuo Iwatac, Yujiro Kitadea, Hiroshi Nagamatsua
aToyko University of Fisheries, Konan, 4-5-7, Minato-ku. Tokyo, 108-8477. Japan
bKanagawa Fisheries Research Institute, Hayakawa. Odawara. Kanagawa. Japan
cMarine Information Research Center, Japan Hydrographic Association. Ginza 7-15-4, Chuo-ku, Tokyo, 104, Japan
Received 12 May 1998; received in revised form 25 January 1999; accepted 16 February 1999
Abstract
On January 9, 1994, a Kyucho (stormy current) rushed along the Sagami Bay coast and destroyed the fishing set-net at the western side of the bay head. The current record at 10 m depth, at a mooring station near the destroyed set-net, showed that the maximum velocity was 0.65 ms-1 with a steep temperature rise, and the strong current continued for about half a day.The thermal front is estimated to have moved cyclonically at the speed of 0.6-0.7 ms-1 from the temperature records at four stations along the bay coast. The successive satellite images, NOAA-IR, also showed the warm water intrusion of the Kuroshio water through the Oshima west channel and moving cyclonically along the coast. The CTD casts in the bay indicated high temperature and high salinity water with the thickness of 70 m and width of 15 km. The behavior of the Kyucho is similar to that of the coastal density current in a rotating fluid, theoretically derived by Kubokawa and Hanawa (1984b). The temperature variations in the Kuroshio region suggest that the Kyucho occurred during the transition period from the non-meander nearshore path of the Kuroshio to the non-large meander offshore path. 1999 Elsevier Science Ltd. All rights reserved.
1. Introduction
Sagami Bay is located on the southeastern coast of Honshu, the main island of Japan, facing the Pacific Ocean, and is about 60 km length, about 50 km wide, and more than 1500 m deep (Fig. 1).
* Corresponding author. Tel.: 0081-3-5463-0456; fax: 0081-3-5463-0456.
E-mail address:masaji@shiho.tokyo-u-fisj.ac.jp(M. Matsuyama)
0278-4343/99/$-see front matter (C) 1999 Elsevier Science Ltd. All rights reserved.
PII: S0278-4343(99)0031-X
