Missing jet search makes one thing clear: Indian Ocean full of trash
Published Monday, March 31, 2014 7:41AM EDT
Last Updated Monday, March 31, 2014 9:24AM EDT
The announcement Monday that four large objects spotted in the Indian Ocean were not from missing Malaysia Airlines Flight 370 but in fact were fishing debris must have been disappointing to family members hoping for answers.
But the news also highlights a wider problem facing investigators scouring the waters for clues: that our oceans are filled with massive amounts of garbage, swirling on the surface.
Marcus Eriksen, an ocean pollution expert and co-founder of the 5 Gyres Institute, says across the world's oceans are five gyres, or systems of rotating ocean currents created by winds and the earth’s rotational forces.
These gyres act like massive, slow-moving whirlpools that gather up garbage on the water's surface and pull them into their vortices.
"In the Indian Ocean, you have cold water coming up from the southern ocean near Antarctica, coming up north along the coast of Perth and then whipping across," Eriksen told CTV's Canada AM Monday from Los Angeles.
"And in these gyres, there can be accumulations of trash coming off our coastlines, falling off of fishing vessels that get stuck in these gyres, where they'll sit for years, or decades."
Within these gyres can be all manner of objects, including glass bottles, rusting metal, plastics, and nylon ropes from fishing traps.
"It's pretty typical to find derelict fishing nets and buoys," Eriksen says.
But while there are large, identifiable pieces in these trash patches, the majority are "small particulates" from broken-down foam cups, plastic bags and other disposable plastics.
One of the largest of these marine debris patches is found in the North Pacific and has been dubbed the Great Pacific garbage patch. It is difficult to pinpoint its size, but the area is several hundred kilometres in diameter. Inside the garbage patch is debris of varying size from big to microscopic.
The area where investigators think that Flight 370 went down more than three weeks ago crosses into the Indian Ocean Gyre. That makes it possible that some of the plane's floating debris, such as seat cushions or composite aircraft parts, could have been swept up into the gyre.
Eriksen says that will make searching for the debris more complicated since it will be hard to distinguish any plane pieces.
"To identify what it is from a passing airplane or a passing ship is very difficult. There's a lot of stuff that's been out there long before this plane crashed," he says.
"So if you see one piece of debris, you don't know how long it's been there or what it is.”
That means that if pilots flying over the area spot a square object, it could be a seat cushion or it could be a gas can from a vessel that went by years ago, Eriksen says.
"So there's lots of confusion about what's out there because there's so much that's accumulating in these gyres."