Fig 2. Concentrations of plastic debris in surface waters of the Mediterranean Sea at basin scale (zoomed in the top right corner inset), and compared to the plastic concentrations reported for the global ocean.
Gray-scale base map in the Mediterranean basin shows the relative surface plastic concentrations predicted by numerical modeling [8]. Darker areas are predicted to have higher concentrations. Major areas of deep-water formation in the Mediterranean are also shown with black circles [24]. In the global map, dark and light gray areas represent inner and outer accumulation zones, respectively, modeled for the five subtropical gyres; white oceanic areas represent non-accumulation zones [7]. Mediterranean map compiles data from the present study and from ref. [20, 21], while open-ocean map compiles measurements of plastic concentrations from ref. [1–5, 10, 11]. Outside the inner accumulation zones, the open-ocean also includes concentrations reported without correction by wind effect (see details in ref. [5]).