The global map shows the sampling effort on measuring plastic debris in the global ocean. Users can select environments (shoreline, surface waters and seafloor) and small or large items, below and above a threshold of about 2 cm, respectively.

Research on marine litter generates huge amounts of information. However, this seeming abundance of information is misleading. Marine litter comprises an extremely heterogeneous assemblage. Plastic is the dominant material, but items made of metal, textile, glass, paper, rubber, wood or ceramic can often be found in the ocean litter. If we focus on plastic items, they can reach up to several meters in length or be as small as a millionth part of one meter. This makes them susceptible to be transported by waves, by bottom currents through submarine canyons, or even by winds, so we find plastic debris everywhere.

Plastic litter is sampled in water, sediment, air, ice or organisms, but these samplings only provide partial views of wide spectrum of plastic sizes present in the nature. Our knowledge about the global distribution of plastic debris is very limited by our ability to integrate and compare datasets. We still don't have a complete vision of the marine litter issue.