Lagrangian Modelling of Plastic Transport and Accumulation around Tenerife Island

Plastic pollution in the marine environment has become a global issue with severe ecological, economic, and social consequences. Oceanic islands are particularly vulnerable, as they combine unique ecosystems with exposure to multiple pathways of plastic leakage, including maritime traffic, fisheries, tourism and hydrodynamic transport. In this study, numerical modelling and field observations are combined to investigate the transport pathways, seasonal variability and accumulation patterns of floating plastic debris in the Canary Islands, with particular focus on Tenerife. Developed within the scope of the PLAST4H2 project (EAPA_0018/2022), funded by the Interreg Programme of the European Union, this work addresses the need for regionally resolved assessments of marine litter dynamics in complex insular systems.The field data analysed comprises 25 beach cleanup campaigns conducted in Tenerife between 2024 and 2025, providing insights into the composition and spatial variability of coastal plastic pollution. Simulations were performed using the MOHID-Lagrangian model, forced by high-resolution three-dimensional metocean data from the Copernicus Marine Service. A model sensitivity analysis was conducted to assess the influence of particle properties and hydrodynamic resolution in the simulated results, alongside an assessment of seasonal variability in transport and accumulation patterns.The sensitivity analysis reveals that variations in particle morphology exert a negligible effect on horizontal transport dynamics, whereas hydrodynamic resolution significantly influences result accuracy. The seasonal simulations show pronounced contrasts across the archipelago: winter conditions promote enhanced mixing and widespread nearshore retention, favouring the persistence of locally sourced debris, while summer circulation dominated by the Canary Current and mesoscale recirculation drives more focused accumulation along Tenerife’s eastern coast.These findings identify persistent accumulation hotspots on Tenerife’s eastern and southwestern shores and emphasise the interplay between regional advection and local recirculation in shaping debris accumulation patterns. This work advances understanding of marine plastic transport in insular environments and provides a transferable framework for future monitoring and mitigation strategies.