Litter on the Arctic Ocean floor has increased drastically since 2002, with plastic waste making up the majority of the debris.

Credit: ALFRED WEGENER INST. POLAR AND MARINE RES.

Melanie Bergmann and Michael Klages of the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany, analysed photographs of the ocean floor captured 2,500 metres below the surface. In 2002, the researchers identified 7 pieces of litter in a survey area of 1,926 square metres. In 2011, they reported 11 pieces in a smaller area — representing a doubling of litter density. Two-thirds of the rubbish was colonized by invertebrate species, including sponges and sea anemones (cardboard and paper packaging with a sponge, pictured).

The increase may be due to shrinking sea ice, which is opening up the ocean to greater human activity and to plastic transported north by the Atlantic current, the authors suggest. With plastic production unlikely to cease, more and more of it may accumulate in the Arctic.

Mar. Pollut. Bull. http://dx.doi.org/10.1016/j.marpolbul.2012.09.018 (2012)