By Chris Mooney
19 April 2017

(The Washington Post) – Drifts of floating plastic that humans have dumped into the world’s oceans are flowing into the pristine waters of the Arctic as a result of a powerful system of currents that deposits waste in the icy seas east of Greenland and north of Scandinavia.

In 2013, as part of a seven-month circumnavigation of the Arctic Ocean, scientists aboard the research vessel Tara documented a profusion of tiny pieces of plastic in the Greenland and Barents seas, where the final limb of the Gulf Stream system delivers Atlantic waters northward. The researchers dub this region the “dead end for floating plastics” after their long surf of the world’s oceans.

The researchers say this is just the beginning of the plastic migration to Arctic waters.

“It’s only been about 60 years since we started using plastic industrially, and the usage and the production has been increasing ever since,” said Carlos Duarte, one of the study’s co-authors and director of the Red Sea Research Center at the King Abdullah University of Science and Technology in Saudi Arabia. “So, most of the plastic that we have disposed in the ocean is still now in transit to the Arctic.”

The results were published Wednesday in the journal Science Advances. The study was led by Andrés Cózar of the University of Cádiz in Spain along with 11 other researchers from universities in eight nations: Denmark, France, Japan, the Netherlands, Saudi Arabia, Spain, the United Kingdom, and the United States.

The researchers estimated that about 300 billion pieces of tiny plastic are suspended in these Arctic waters right now, although they said the amount could be higher. And they think there is even more plastic on the seafloor. [more]

The pristine Arctic has become a garbage trap for 300 billion pieces of plastic


Locations and plastic concentrations of the sites sampled. The summer extension of the polar ice cap in August 2013 is shown in white area, and the classical schematic drawing of the North Atlantic Subtropical Ocean Gyres and the Global Thermohaline Circulation poleward branch is indicated by green curves. The northern passage from Barents Sea to Kara Sea is zoomed in, with contour lines describing salinity measured at a depth of 5m. Graphic: Andres Cozar

By Hayley Dunning
19 April 2017

(Imperial College London) – Plastic waste entering the seas from both sides of the North Atlantic is accumulating in the Arctic Ocean, where it can damage local wildlife.

The low population of the Arctic Circle means little plastic waste is generated there. However, a new study has shown that the Greenland and Barents Seas (east of Greenland and north of Scandinavia) are accumulating large amounts of plastic debris that is carried and trapped there by ocean currents.

The new study, published today in Science Advances, found that the Greenland and Barents seas have accumulated hundreds of tons of plastic debris composed of around 300 billion pieces, mainly fragments around the size of a grain of rice. The vast majority of these fragments originate form the North Atlantic.

The team behind the study is composed of researchers from eight countries, led by Professor Andrés Cózar from the University of Cadiz in Spain, and including Dr Erik van Sebille from the Grantham Institute at Imperial College London.

Plastic is transported from the North Atlantic to the Arctic by the Gulf Stream, a huge ocean current that also carries warm waters from the Gulf of Mexico to northern Europe and the US east coast.

Once it gets to the Arctic Ocean, this current sinks and travels back to the equator, but the plastic does not sink with it, leaving it to build up in Arctic waters.

Ecosystem under threat

Plastic is a problem for local wildlife as marine organisms mistakenly eat, are poisoned by, or become tangled in floating plastic, which damages their health and can kill them.

Dr van Sebille, who now works at Utrecht University, said: "The Arctic is one of the most pristine ecosystems we still have. And at the same time it is probably the ecosystem most under threat from climate change and sea ice melt. Any extra pressure on the animals in the Arctic, from plastic litter or other pollution, can be disastrous.”

The team sailed on an expedition to the Arctic Ocean in order to complete a global map of floating plastic pollution. The expedition lasted five months and circumnavigated the Arctic ice cap aboard the research vessel Tara.

Professor Cózar said: “The plastic concentrations in the Arctic waters were usually low, but we found an area located in the north of the Greenland and the Barents seas with quite high concentrations. There is continuous transport of floating litter from the North Atlantic, and the Greenland and Barents seas act as a dead-end for this poleward conveyor belt of plastic.”

Prevention is the cure

To find the fate of plastic in the North Atlantic, team used data from over 17,000 drifting satellite-tracked buoys floating on the surface of the ocean. They then pieced together how the plastic ended up in the Arctic hotspots by using advanced statistics, which model how ocean currents move these buoys.

Dr van Sebille said: "What is really worrisome is that we can track this plastic near Greenland and in the Barents Sea directly to the coasts of northwest Europe, the UK and the east coast of the US. It is our plastic that ends up there, so we have a responsibility to fix the problem.

"We need to stop the plastic from going into the ocean in the first place. Once the plastic is in the ocean, it's too diffusive, too small and too intermingled with algae to easily filter out. Prevention is the best cure."

Floating plastic pollution from Europe and the US is accumulating in the Arctic


Photo collage of plastic fragments found in the Arctic Ocean. Although plastic debris was scarce in most of the Arctic waters, it reached high concentrations in areas of the Greenland and Barents seas. Photo: Andres Cozar

ABSTRACT: The subtropical ocean gyres are recognized as great marine accumulation zones of floating plastic debris; however, the possibility of plastic accumulation at polar latitudes has been overlooked because of the lack of nearby pollution sources. In the present study, the Arctic Ocean was extensively sampled for floating plastic debris from the Tara Oceans circumpolar expedition. Although plastic debris was scarce or absent in most of the Arctic waters, it reached high concentrations (hundreds of thousands of pieces per square kilometer) in the northernmost and easternmost areas of the Greenland and Barents seas. The fragmentation and typology of the plastic suggested an abundant presence of aged debris that originated from distant sources. This hypothesis was corroborated by the relatively high ratios of marine surface plastic to local pollution sources. Surface circulation models and field data showed that the poleward branch of the Thermohaline Circulation transfers floating debris from the North Atlantic to the Greenland and Barents seas, which would be a dead end for this plastic conveyor belt. Given the limited surface transport of the plastic that accumulated here and the mechanisms acting for the downward transport, the seafloor beneath this Arctic sector is hypothesized as an important sink of plastic debris.

The Arctic Ocean as a dead end for floating plastics in the North Atlantic branch of the Thermohaline Circulation

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