Impact of ocean waves on transport of underwater spilled oil in the Bohai Sea

Abstract

To investigate the impact of ocean waves on transport of underwater spilled oil, a wave action module is developed and embedded into an underwater oil spill model. Combined with a validated hydrodynamic background data, the model is applied to a short-term numerical simulation of the 2011 Penglai 19-3 oil spill event in the Bohai Sea. Numerical result shows that the model result is rationally consistent with the field observation. In addition, waves can influence surface oil slick in both horizontal and vertical directions: in horizontal direction, Stokes drift tends to make oil slick spread more widely under the action of wind-waves; in vertical direction, breaking waves tend to entrain the surface oil into water column, and then affects the vertical distribution of spilled oil. Furthermore, sensitivity study shows that using different parameterizations of wave entrainment can make some difference to the model output, but the effect is limited. Besides, the impact of input wave errors varies on different model outputs. This study is expected to provide offshore oil spill emergency responders and researchers with useful information on oil spill monitoring, emergency plans and environmental damage assessment.

Keywords: Environmental damage assessment; Numerical simulation; Ocean waves; Ocean waves errors; Oil entrainment parameterization; Underwater oil spill.