Effect of oil plumes on upper-ocean radiative transfer – a numerical study

Numerical simulations are performed to study the effect of oil plumes on upper-ocean light field. The simulations are done using a set of numerical models that are designed to capture the detailed transport phenomena of oil by turbulence and waves in the ocean mixed layer and the light transfer through this complex medium. Particularly, the dispersion of the oil plume is simulated using the large-eddy simulation method, the sea-surface wave is simulated using the high-order spectral method, and the sunlight field variation is simulated using a Monte Carlo radiative transfer model. The simulation results show that, when interacting with flows in the ocean mixed layer, oil plumes of different droplet sizes exhibit very different dilution patterns in terms of plume size, shape and oil concentration. With the same volumetric release rate, plumes of large oil droplets exhibit highly intermittent local preferential concentration in near-surface regions and cause strong but intermittent sunlight extinction over relatively small horizontal area; plumes of small oil droplets diffuse more smoothly over large horizontal and vertical extensions, resulting in much more significant overall extinction effect to the sunlight penetration in the ocean euphotic zone. This dataset is associated with the manuscript "Effect of oil plumes on upper-ocean radiative transfer - a numerical study" submitted to Ocean Modelling.