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Author Fukasawa, Masao ♦ Teramoto, Toshihiko ♦ Taira, Keisuke
Source CiteSeerX
Content type Text
File Format PDF
Subject Domain (in DDC) Computer science, information & general works ♦ Data processing & computer science
Subject Keyword Shikoku Basin ♦ Hydrographic Structure ♦ Deep Boundary Current ♦ Heavier Water ♦ Nankai Trough ♦ Vertical Scale ♦ Good Agreement ♦ Continental Shelf-toe ♦ Cape Shiono-misaki ♦ Vorticity Balance ♦ Eastern Flank ♦ Assumed Level ♦ Kyushu-palau Ridge ♦ Volume Transport ♦ Planetary Vorticity ♦ Thermal Wind Shear ♦ Hydrographic Data ♦ Sea Bottom ♦ Horizontal Extent ♦ Northern End ♦ Latitudinal Variation ♦ Direct Current Measurement ♦ High Quality Ctd Data ♦ Saltier Water ♦ Salinity Water
Abstract High quality CTD data were collected in the north of the Shikoku Basin where an abyssal boundary current has been observed through direct current measurements. Analyses of hydrographic data showed: 1. Colder and saltier water (heavier water) compared to surrounding waters is found above the continental shelf-toe and the eastern flank of the Kyushu-Palau Ridge where the existence of the abyssal boundary current has been expected. The heavier water has a horizontal extent of about 50 km. 2. The heavier water has the vertical scale of 2000 m from the sea bottom, and is associated with a thermal wind shear which enhances a component of the flow toward a direction looking the Nankai Trough (a trough located along the northern end of the Shikoku Basin) to the left in the abyss. The assumed “level of no motion ” at about 2500 m depth gives the geostrophically estimated current in a good agreement with the directly measured current. A volume transport associated with the colder and higher salinity water is estimated to be about 2 Sv off Cape Shiono-misaki which may include a recirculation above the Nankai Trough. This is about twice of the transport estimated in the interior of the Shikoku Basin through a vorticity balance between the stretching term and latitudinal variation of the planetary vorticity. 1.
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Research
Education Level UG and PG ♦ Career/Technical Study
Publisher Date 1994-01-01