Numerical Modeling of Tide and Tide-Induced Drifting of Particles Released from the Sunken Ship in the Southeastern Yellow Sea

Abstract

Casualties released from a sunken ship off the southwestern tip of the Korean peninsula on April, 2014 show a particular trend of moving mainly northward around the complicated coastal area, where strong tidal currents prevail. In order to understand how this takes place and to also examine tidal and residual current features in the region, fine grid tidal modeling has been carried out in this sub region of the southeastern Yellow Sea. A detailed study of the phase and sea level slope differences in the several waterways off the southwestern tip of Korean peninsula suggests that there are noticeable differences in the dominant M2 tidal current speed. Analyses of tidal currents in terms of the in-phase and quadrature velocity components reveal that both the standing and progressive characters are competitive in this area It is shown that the M2-driven tidal residual currents are dominated, with the northward residual currents prevailing just near the sunken ship, and generally intensified northward residual currents in the surrounding region. The accuracy of the particle trajectory modeling was validated by showing that the locations of 3 casualties (among 300 persons) found outside the sunken ship off southwestern tip of Korean peninsula on April 16, 2014 were within the predicted locations estimated by the particle trajectory method. In particular, it is shown that the general northward scattering pattern of continuously released particles for 15 days is likely to result from the M2-driven residual currents in this region. This should be useful information for future rescue purposes.