Ocean Plastic Hiding Below the Surface

Winds are stirring plastic pollution in the ocean deep below the surface.

From the deck of a research vessel, Giora Proskurowski, a marine chemist at the University of Washington, gazed out over a plethora of tiny plastic pieces bobbing on the Pacific Ocean.

Proskurowski noticed that the wind repeatedly forced tiny bits of plastic beneath the water. Since studies of the amount of plastic waste in the ocean are normally done by skimming only the surface, he realized that decades of previous studies may have seriously underestimated the amount of garbage in the ocean.

After a test of his observation pulled up plastic from 16 feet beneath the surface, Proskurowski developed a method for pulling up plastic as deep as 100 feet. He tested his method in the North Atlantic.

"Almost every tow we did contained plastic regardless of the depth," Proskurowski said in a press release.

Proskurowski calculated that previous studies may have been underestimating the total amount of plastic by a factor of 2.5 up to 27, depending on the strength of the wind.

"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," Proskurowski said.

The submerged plastic measuring system could become the new standard for measuring the amount of plastic in the ocean. If so, it could change the way policymakers plan to deal with the plastic pollution drifting with the ocean currents, most of which is widely dispersed in millimeter-sized bits of debris.

"On this topic, what science needs to be geared toward is building confidence that scientists have solid numbers and that policymakers aren't making judgments based on CNN reports," Proskurowski said.

Top photo: Plastic debris littering Hawaiian shoreline. Hawaii is located near the center of the North Pacific gyre, where debris tends to concentrate. Hawaii, Hawaii. Credit: Eric Johnson, NOAA, Wikimedia Commons.

Bottom photo: Giora Proskurowski deploys a net to collect samples that help estimate how much plastic debris is in the ocean. Credit: Sea Education Association.