Observations and Simulations of the Circulation and Mixing around the Andaman-Nicobar Submarine Ridge

Using data collected by an Acoustic Doppler Current Profiler(ADCP) on a research cruise in April 2010 in the eastern Indian Ocean,the vertical current structures surrounding the Andaman-Nicobar Submarine Ridge(ANSR) are analyzed to investigate the hydrographic responses to the topography in this region.The results show that the topography of ANSR can induce internal waves around the submarine ridge that have a maximum current velocity of 1 m s-1.The spatial structure of the turbulent kinetic energy(TKE) and shear in this region during 2010 is investigated using the high-resolution Princeton Ocean Model(POM) forced by the satellite-based Advanced Scatterometer(ASCAT) winds including the tide.The results show that the model successfully simulates the internal waves around the ANSR.Numerical experiments further indicate that both the topography and tide play an important role in the generation of the internal waves in this region.