LAUSR

Abstract Oil plumes released from subsea blowouts can induce strong optical extinction effect and significantly affect radiative transfer in the ocean euphotic zone where photosynthesis occurs. In this paper, the effect of oil plumes on the ocean radiative transfer is studied numerically by modeling the dispersion of oil plume in the ocean mixed layer and the radiative transfer through the oil-contaminated seawater. Due to the interactions with flows in the ocean mixed layer, oil plumes of different droplet diameters exhibit considerable differences in plume size, shape and oil concentration. With the same volumetric release rate, plumes of large oil droplets exhibit highly intermittent local concentration in near-surface regions and cause strong but intermittent extinction effect over relatively small horizontal area; plumes of small oil droplets diffuse more smoothly over large horizontal and vertical extensions, resulting in significant overall extinction effect to the radiative transfer in the ocean euphotic zone.