Oceanic 'Garbage Patch' smaller than claimed
The amount of plastic trash floating in the Pacific Ocean's 'Great Garbage Patch' is nowhere near as great as has been made out, an Oregon State University scientist says.
Nor is it true that the oceans are filled with more plastic than plankton, or that the patch has been growing tenfold each decade since the 1950s.
"There is no doubt that the amount of plastic in the world's oceans is troubling, but this kind of exaggeration undermines the credibility of scientists," says Angelicque White, an assistant professor of oceanography at Oregon State.
"We have data that allow us to make reasonable estimates; we don't need the hyperbole. Given the observed concentration of plastic in the North Pacific, it is simply inaccurate to state that plastic outweighs plankton, or that we have observed an exponential increase in plastic."
White says that an examination of the published literature and data from field expeditions shows that the hypothetically 'cohesive' plastic patch is actually less than one percent of the geographic size of Texas.
"The amount of plastic out there isn't trivial," White said. "But using the highest concentrations ever reported by scientists produces a patch that is a small fraction of the state of Texas, not twice the size."
Recent research by the Woods Hole Oceanographic Institution found that the amount of plastic in the Atlantic Ocean, hasn't increased since the mid-1980s - despite greater production and consumption of the stuff.
"Are we doing a better job of preventing plastics from getting into the ocean?" White said. "Is more plastic sinking out of the surface waters? Or is it being more efficiently broken down? We just don't know. But the data on hand simply do not suggest that 'plastic patches' have increased in size."
White says that removing plastic from the ocean, but such efforts will be costly, inefficient, and may have unforeseen consequences. It would be difficult, for example, to 'corral' and remove plastic particles from ocean waters without inadvertently removing phytoplankton, zooplankton, and small surface-dwelling aquatic creatures.
"These small organisms are the heartbeat of the ocean," she said. "They are the foundation of healthy ocean food chains and immensely more abundant than plastic debris."
Plastic, White points out, also covers the ocean floor, particularly near large population centers. A recent survey found that three percent of the southern California Bight's ocean floor was covered with plastic.
But some areas of the ocean are largely clear of plastic: a recent trawl of a remote section of water between Easter Island and Chile pulled in no plastic at all.
"If there is a takeaway message, it's that we should consider it good news that the 'garbage patch' doesn't seem to be as bad as advertised," White said, "but since it would be prohibitively costly to remove the plastic, we need to focus our efforts on preventing more trash from fouling our oceans in the first place."