Forecasting marine debris spill accumulation patterns in the south-eastern Australia water: an intercomparison between global ocean forecast models

Forecasting transport and fates of marine debris spilled from lost ship containers is increasingly important. This paper builds a forecast framework by forcing a state-of-the-art particle-tracking model with operational oceanic and atmospheric forecasts, and compares simulations with the spotted debris from an actual maritime container spill in the south-eastern Australia water. In coastal areas, patterns of the spotted debris can be approximately simulated when applying surface current forecasts of an eddy-resolving resolution, along with the horizontal dispersion, Stokes drift and windage. The strengths and shortcomings of various forecast datasets varied. Therefore, a thorough analysis of various forcing datasets might be required when performing a marine debris forecast. The horizontal dispersion coefficient can be used to parameterize the unresolved small-scale processes. Stokes drift and windage, especially the latter one, can be important for the debris movements. This study suggests that some global forecast models can be used with certain confidence to forecast debris movement, however, not all are equivalent and cautions are warranted.