Tracking the Spread of Plastic Pollution from Liberian Rivers: A Case Study in the Gulf of Guinea

This study addresses the pressing issue of marine pollution caused by plastic waste, primarily originating from sources like rivers, coastal areas, and industrial discharges. It focuses on Liberia's five main rivers, employing an adapted TrackMPD model to track particle movement over an extended period. The study introduces innovative outputs: density and beaching maps. Part of the GDA AID Marine Environment & Blue Economy initiative, in collaboration with the European Space Agency, Asian Development Bank, and World Bank, the project utilizes advanced Earth Observation services. It supports International Funding Institutions in marine and Blue Economy ventures, aligning with the World Bank's PROBLUE and West Africa Coastal Areas (WACA) programs. Simulations ran daily throughout 2021, incorporating Copernicus marine services data on sea current fields. The results confirm the widespread challenge of plastic pollution in marine environments. The study region spans the West African coast, with macroplastic particles released from Liberian rivers. The modified TrackMPD model tracked daily releases from known locations, at a spatial scale of approximately 9 km and a temporal scale of 1 day. The density map indicates particle count per pixel, while the beaching map shows density within a coastal buffer zone of about 18 km. This study underscores the gravity of the plastic pollution crisis, emphasizing the need for global cooperation. It highlights that discharges from Liberia's rivers can affect areas far from their origin. Future improvements may involve using different driving data, including hourly sea current fields, and real-world case studies with in-situ sampling. The World Bank also suggests testing a 3D model and considering factors like biofouling and refloating to estimate plastic sources near Mauritania through backward simulation.