Plastic debris does not remain on the surface forever. Eventually it starts to sink. Cold, dense water sinks in the North Atlantic and Southern Ocean, driving what is often referred to as the ocean conveyor belt or thermohaline circulation. This deep water circulation pattern couples with the subtropical gyres and redistributes cooled waters towards the deep ocean layers. The combination of these currents could provide a mechanism for enhanced vertical dispersion of near-neutrally buoyant plastic particles and debris; further research is required.
From collection: Marine Litter Vital Graphics
GRID-Arendal and Maphoto/Riccardo Pravettoni