Oceanographic modelling and monitoring are both widely used to study the pathways and fate of marine pollutants such as hydrocarbons, plastic litter, suspended sediments, radionuclides, etc. In this session, advanced models, operational applications and techniques related to tracing pollutants on local, regional and global scales, as well as the coupling with met-oceanographic transport fields from operational oceanography products such as Copernicus Marine Monitoring Environment Service will be discussed.
Parcel trajectory numerical schemes, ensemble and multi-model methods, uncertainties estimation, risk algorithms, monitoring techniques and decision support systems are solicited topics. Integration of modelling and observing systems for both data assimilation and model validation are also very welcome.
Key questions of the session are identified as follows.
Which factors affect the dispersion of the oil, floating debris and other pollutants?
What happens to the contaminants on the ocean’s surface and in the water column?
How do oil, marine litter and other pollutants interact with water and sediments?
Impacts of pollutants on the marine ecosystems and resilience to pollution events are also important subjects for discussion: What are the oil’s, plastics’, and sediments’s behavior in the water column, on various beach sediments, rocks and seabed? 
E.g., what is the biodegradation rate of oil droplets remaining in the water column and what are the controlling factors? What is the rate of aggregation, biofouling, degradation and fragmentation of plastics?
What is the rate of beaching and sedimentation of marine pollutants and what are the ways of entering the marine food chains (including human consumption)?