Volume transport of the Soya Warm Current revealed by bottom-mounted ADCP and ocean-radar measurement

The vertical structure of the Soya Warm Current (SWC) was observed by a bottom-mounted acoustic Doppler current profiler (ADCP) in the region of the SWC axis near the Soya Strait during a 1-year period from May 2004. The ADCP data revealed a marked seasonal variability in the vertical structure, with positive (negative) vertical shear in summer and fall (winter and spring). The volume transport of the SWC is estimated on the basis of both the vertical structure observed by the ADCP and horizontal structure observed by the ocean radars near the strait. The transport estimates have a minimum in winter and a maximum in fall, with the yearly-averaged values in the range of 0.94–1.04 Sv (1 Sv = 106 m3 s−1). These lie within a reasonable range in comparison to those through other straits in the Japan Sea.

[1]  Kay I. Ohshima,et al.  The flow system in the Japan Sea caused by a sea level difference through shallow straits , 1994 .

[2]  Lynne D. Talley,et al.  An Okhotsk Sea water anomaly: implications for ventilation in the North Pacific , 1991 .

[3]  Kuh Kim,et al.  Subinertial to interannual transport variations in the Korea Strait and their possible mechanisms , 2005 .

[4]  Arata Kaneko,et al.  Seasonal variability in the Tsushima Warm Current, Tsushima-Korea Strait , 1994 .

[5]  W. Teague,et al.  Low-Frequency Current Observations in the Korea/Tsushima Strait , 2002 .

[6]  M. Wakatsuchi,et al.  Formation of 26.8-26.9 water in the Kuril Basin of the Sea of Okhotsk as a possible origin of North , 1998 .

[7]  M. Matsuyama,et al.  Current structure and volume transport of the Soya Warm Current in summer , 2006 .

[8]  Sawa Matsuyama,et al.  Seasonal Variation of Soya Current. , 1999 .

[9]  M. Matsuyama,et al.  Tidal current fluctuations in the Soya Current , 1987 .

[10]  Tomoharu Nakayama,et al.  Variation of velocity and volume transport of the Tsugaru Warm Current in the winter of 1999–2000 , 2003 .

[11]  Jong Hwan Yoon,et al.  The Tsushima Warm Current through Tsushima Straits Estimated from Ferryboat ADCP Data , 2005 .

[12]  Naoto Ebuchi,et al.  Observation of the Soya Warm Current using HF ocean radar , 2006 .

[13]  Ichiro Yasuda,et al.  The origin of the North Pacific Intermediate Water , 1997 .

[14]  P. Hwang,et al.  Transport variability across the Korea/Tsushima Strait and the Tsushima Island wake , 2005 .

[15]  Yoshinori Nishida,et al.  Seasonal and Interannual Variations of the Volume Transport through the Tsugaru Strait. , 2003 .

[16]  T. Takizawa Characteristics of the Sôya Warm Current in the Okhotsk Sea , 1982 .