Litter Levels in the Depths of the Arctic are On the Rise

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The Arctic has a serious litter problem: in just ten years, the concentration of marine litter at a deep-sea station in the Arctic Ocean has risen 20-fold. This was recently reported in a study by researchers at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI).

The Arctic has a serious litter problem: in just ten years, the concentration of marine litter at a deep-sea station in the Arctic Ocean has risen 20-fold. This was recently reported in a study by researchers at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI).

Plastic bags, glass shards and fishing nets: despite its location, far from any urban areas, the amount of litter in the depths of the Arctic Ocean continues to rise, posing a serious threat to its fragile ecosystem. Since 2002, AWI researchers have been documenting the amount of litter at two stations of the AWI’s “Hausgarten”, a deep-sea observatory network, which comprises 21 stations in the Fram Strait, between Greenland and Svalbard. The results of the long-term study have now been published in the scientific journal Deep-Sea Research I. “Our time series confirms that litter levels in the Arctic deep sea have risen rapidly in the past few years,” says first author and AWI biologist Mine Tekman.

The scientists involved in the study observed the ocean floor at a depth of 2,500 metres using the OFOS (Ocean Floor Observation System), a towed camera system. Since the start of their measurements, they have spotted 89 pieces of litter in a total of 7,058 photographs. To enable comparison with other studies, the researchers have extrapolated the litter density to a larger area. The result: an average of 3,485 pieces of litter per square kilometre in the monitoring period (2002 to 2014). Further, there has been a clearly recognizable increase in the past few years: when the team calculated a contamination level of 4,959 pieces of litter per square kilometre for 2011 in an earlier study, they hoped it was a statistical outlier. But the levels have continued to rise since, reaching a new peak of 6,333 pieces of litter per square kilometre in 2014. 

The situation is particularly dramatic at the network’s northern station, called N3. “Here the amount of litter rose more than 20-fold between 2004 and 2014,” says Tekman. If we consider the findings for the northern research area in the marginal ice zone, the data for 2004 indicated 346 pieces of litter per square kilometre. Ten years later, the number had risen to 8,082. The level of contamination is similar to one of the highest litter densities ever reported from the deep seafloor, in Cap de Creus Canyon off the eastern coast of the Iberian Peninsula.

Read more at Alfred-Wegener-Institut

Photo credit: OFOS/James Taylor