PMAR: A Lagrangian approach to the modelling of anthropogenic pressures for marine management

PMAR (Pressure models for MARine activities) is a modelling framework and open-source Python-based software designed to assess anthropogenic pressures for marine management. PMAR uses Lagrangian trajectories calculated from ocean models to simulate pressure dispersion. An explicit link between pressures and their sources is established through a weight-based mechanism, which allows to rapidly explore different pressure source scenarios. Here, PMAR is adopted to investigate the distribution of surface macroplastics in the Black Sea under two scenarios, yielding results consistent with previous modelling studies and observations. Over 50% of the macroplastics in each Black Sea country after a yearly run came from elsewhere, stressing the importance of cross-boundary cooperation. Compared to other pressure modelling frameworks, PMAR emerges as a balanced compromise between computational efficiency and predictive accuracy. Future work will focus on making PMAR accessible to decision-makers and aligning it with requirements of Digital Twin of the Ocean applications.