Internal tide near Danzyo Gunto in Eastern China Sea.

Abstract

Internal tide was observed near Danzyo Gunto in Eastern China Sea The amplitude of temperature fluctuation of M2 tidal frequency was l℃ at 90 m depth where thermocline was situated. According to the vertical profile of temperature, it coincided with.the vertical motion whose amplitude was 10 m. If temperature fluctuation was caused by the first mode internal wave, the amplitude of horizontal current was 27 cm/sec at the surface layer. In its velocity field, we track the motions of fluid particles numerically. As a result, particles at the surface layer move more than 2 km over 1 cycle in the direction which the wave propagates. On the other hand, particles in the middle layer move in the opposite direction.