Winter transport and tidal current in the Tsugaru Strait

Onishi, Mitsuyo*; Isoda, Yutaka*; Kuroda, Hiroshi*; Iwahashi, Masayuki*; Sato, Chizuru*; Nakayama, Tomoharu*; Ito, Toshimichi; Iseda, Kenichi*; Nishizawa, Keisuke*; Shima, Shigeki*; et al.

Hokkaido Daigaku Suisan Kagaku Kenkyu Iho, 55(2), p.105 - 119, 2004/10

http://ci.nii.ac.jp/naid/110000954121

Transport variations and characteristics of tidal currents in the Tsugaru Strait (TS) are investigated using the ship-mounted ADCP data obtained during October 29, 1999 - March 31, 2000. The Tsugaru Strait connects the North Pacific Ocean (NPO) and Japan/East Sea (JES), and is a main output for Tsushima Warm Current (TWC) in the JES. The strong northeastwards mean current was found in the center of the strait, and counter flows exist near the Hokkaido and Honshu coasts. The estimated mean net eastward transport is 1.8 Sv (1Sv=10ms). In the TS, the transports of K1 and M2 across the strait are 0.72 Sv and 0.52 Sv, respectively. From the phase analysis, it is understood the K1 is progressive wave-like while the M2 is standing wave-like. We also find a significant barotropic fortnightly oscillation. The Mf tide is more energetic along the JES coast with the amplitude of 1-3cm, while the Mf tide amplitudes in the NPO are less than 1 cm. It is inferred that observed fortnightly oscillation may be generated by the difference of Mf tide amplitude between both sides of the TS.