A new study, published Wednesday in Science Advances, shows that a major ocean current is depositing bits of plastic from the North Atlantic onto the surface waters, sea ice, and possibly the ocean floor of the Greenland and Barents seas. The researchers also forecasted further increases in plastic pollution in the region, as shrinking sea ice from climate change makes navigation easier, and human activity in the area increases. Plastic pollution around the world has seen dramatic increases since the 1980s, and this phenomenon is likely to contribute that pollution in the Artic over the coming decades.
The study’s lead author, Andrés Cózar Cabañas, said the results were surprising and alarming.
“We don’t fully understand the consequences the plastic is having or will have in our oceans. What we do know is that consequences will be felt at greater scale in an ecosystem like this,” he said.
8 million tons of plastic are dumped into the world’s oceans annually. Scientists have estimated that as much as 110 million tons of plastic trash are in the ocean currently. The environmental effects of this phenomenon are not fully understood, but scientists have found the plastic has made its way into the food chain.
Earlier thinking assumed most of the plastic was accumulating in large patches, particularly in subtropical gyres, which are large currents converging in the center of the ocean. However, researchers have now estimated that only 1 percent of this plastic is ending up in gyres and other open ocean surface waters.
Another model by one of the authors of the new study forecasted that plastic pollution could accumulate in the Arctic Ocean, especially in the Barents Sea, off of the northern coasts of Russia and Norway. The new study demonstrates exactly that. That part of the ocean plays an important role in thermohaline circulation – a global current affected by temperature and salinity differences around the world. That current brings warm water to the Arctic, and now seems to carry plastic pollution from more densely populated parts of the world. There, the plastic is trapped by large masses of land such as Greenland.
The study took samples of plastic from 42 sites in the Arctic Ocean, in 2013.
Cabanas said the study shows the need for international agreements to address the plastic problem, given that it spreads without regard for national borders.
“This plastic is coming from us in the North Atlantic. And the more we know about what happens in the Arctic, the better chance we have,” he said.