Monitoring of floating macro litter in the Arctic seas and rivers

Among other marine environmental problems, the issue of marine litter accumulation in the World Oceans is of increased interest. It is relevant not only in areas with direct intense anthropogenic pressure, but also in remote and presumably pristine areas, such as the Arctic Sea. As the concentration of plastic waste in the marine environment increases, it can have impacts on various components of the marine ecosystem, at sea, on the seafloor, on the coasts and in particular in accumulation areas, while it also can negatively affect human social and economic activities. To reduce the release of plastic debris into the marine environment, litter occurrence and pathways need to be studied in order to identify litter sources, requiring monitoring studies that provide comparable results. Here we present the results of studies of the level of pollution by marine litter floating at sea and flowing with rivers in the Arctic region. Ship-based visual observations at sea were performed in the period 2019-2021 in the White Sea, the Barents Sea, the Kara Sea, the Laptev Sea and the East Siberian Sea. To assess the floating litter input with rivers, regular observations (2 times a month) were carried out by the trained observers on the Northern Dvina and Onega rivers. In all cases a standardized methodology was applied to obtain a unified data and to record the data a Floating Macro Litter mobile application (JRC) was used. The methodology contains a unified list and classification of observed floating sea/riverine litter items, which simplifies the data processing and analysis and allows to compare the data. For the first time a large scale assessment of litter pollution was performed in these remote Arctic regions. The international methodology confirmed the possibility of collecting unified data in the region and at the same time revealed some regional features.