There's far more little bits of plastic in the ocean than previous studies have indicated, according to new research.
While armadas of plastic ducks might make the headlines, it's tiny pieces that cause most concern to environmentalists. Fish are believed to suffer liver damage from ingesting plastic, for example, and there's evidence it can even be transferred to people who eat seafood.
While working in the Pacific Ocean, University of Washington oceanographer Giora Proskurowski noticed that while the water was covered with tiny pieces of plastic, most disappeared the moment the wind picked up.
And, after taking samples of water at varying depths, he discovered that the wind was pushing the lightweight particles below the surface - meaning that decades of research conducted by skimming the surface have been producing the wrong results.
Indeed, he says, such research has been underestimating the total amount of plastic in the water by two and a half times - and by as much as 27 times in high winds.
"Almost every tow we did contained plastic regardless of the depth," he says.
The team developed a mathematical model that incorporates wind measurements to improve estimates of how much plastic waste is in our oceans.
"By factoring in the wind, which is fundamentally important to the physical behavior, you're increasing the rigor of the science and doing something that has a major impact on the data," says Proskurowski.
Now, Proskurowski hopes to examine additional factors, including the drag of the plastics in water, complex ocean turbulence and wave height, that might improve the accuracy of the model.