Consider this: The amount of global trash is expected to rise every year for the rest of the century. With no intervention, the growing garbage heap won't even peak by 2021.
Since most marine debris originates on land, that grim prognosis, say researchers at the University of Georgia, could spell disaster for the oceans, creating an environmental hazard often compared in scope with climate change.
"We estimate we're going to have millions of tons of plastic going into the ocean with, so far, unknown consequences," says Jenna Jambeck, an environmental engineer at the university, who is among a group of scientists pursuing a new phase of research on ocean trash and measuring its impact on the environment and marine life. The University of Georgia group works as part of the University of California at Santa Barbara's National Center for Ecological Analysis and Synthesis.
But while climate change is still mired in politics and is a target of naysayers, the trouble in the oceans is an easier issue to address because it is so visible. "The one thing this issue has going for it over climate change is that you can see the garbage," Jambeck says.
Ocean debris grabbed the international spotlight this spring during the search for the missing Malaysian jet, when multiple satellite images of floating debris repeatedly turned out to be garbage instead of pieces of the Boeing 777. (See "Plane Search Shows World's Oceans Are Full of Trash.")
Secretary of State John Kerry hopes to highlight the issue again next week by making marine trash one of the main topics at a two-day oceans conference that begins Monday. Kerry hopes to frame the challenges that lie ahead, including climate change-related ocean acidification and the threat of overfishing.
But the dilemma caused by the growing tonnage of mostly plastic debris is so complex, it has created a new interdisciplinary field of study. Scientists like Jambeck are examining a litany of new issues that range from the toxicity of plastics ingested by marine animals to the politics and economics of solid waste management in developing nations.
New Questions for an Old Problem
Seafarers have known for decades that the oceans are trash dumps, the ultimate sinkholes for all global garbage. So far, 136 species of marine animals have been found entangled in debris. According to the National Oceanic and Atmospheric Administration, the first such discovery was made in 1944, when northern fur seals turned up trapped in rubber "collars" that were the remains of Japanese food-drop bags from the Aleutian campaign in World War II.
But scientific research into marine garbage is only a decade or so old. NOAA, for example, launched its Marine Debris Program only in 2006, after Congress passed the Marine Debris Act at the urging of Senator Daniel Inouye (D-Hawaii).
The defining moment of ocean debris research, says Jambeck, was when scientists discovered that ocean debris was no longer an assemblage of cloth, wood, and ceramics, but was composed almost entirely of plastic. Most of that is micro-plastic, meaning it has decayed and broken down into microscopic pieces that float in the water column. Richard Thompson, a British scientist scheduled to speak at Kerry's conference, first highlighted the problem in 2004 in a paper titled "Lost at Sea: Where Is All the Plastic?"
"Once micro-plastics entered the picture and it was being ingested by marine life, it was a whole new ballgame," Jambeck says. "That's when the alarms started going off."
Jambeck and her team's research, to be published later this year, will provide new estimates of how much garbage is produced globally every year, how much garbage comes from developing countries lacking garbage collection systems, and how much litter is produced by developed countries. All trash has the potential to reach the oceans.
Yet despite the new burst of scientific study, solving the problem in the face of an increasing volume of ocean trash seems an almost insurmountable task.
Options Are Few: Cleanup or Prevention
An alliance of 48 plastic manufacturers from 25 countries—all members of the Global Plastics Associations for Solutions on Marine Litter—has pledged to help prevent marine debris and encourage recycling. Several manufacturers are now marketing products made partly from recycled ocean plastics and abandoned fishing gear.
But the consensus among many scientists, including NOAA's, is that cleaning up the oceans can potentially cause more harm than good. Cleaning up micro-plastics could also inadvertently sweep up plankton, which provides the basis for the marine food chain and half of the photosynthesis on Earth.
Ocean trash is driven by currents into loosely formed garbage "patches" that Dianna Parker, a NOAA spokesperson, says are more accurately described as "peppery soup" filled with grain-size plastic bits. The word "patch" suggests a defined size and location, when in fact floating debris is constantly moving, shifting with seasonal weather, and changing in shape and size.
Cleaning up even one of these areas seems impossible. Not surprisingly, the largest patch is in the largest ocean—the Pacific, which covers a third of the planet. The Great Pacific Garbage Patch, as it is known, is often said to be twice the size of Texas. It actually extends, at times, from Japan to San Francisco, and varies in shape and density. According to NOAA, cleaning up less than one percent of the North Pacific would take 68 ships working 10 hours a day for a year.
Beach cleanups help, but are costly and ineffective. The Ocean Conservancy, the international leader in coastal cleanups, has collected some 180 million tons in three decades of work. "We have now created the world's best database for what actually happens on our beaches," says Andreas Merkl, the group's CEO. "We are the largest end-of-the-pipe, ocean-specific trash entity."
San Francisco spends $6 million a year cleaning up cigarette butts alone, according to NOAA figures in a report called the "The Honolulu Strategy: A Global Framework for Prevention and Management of Marine Debris." The Honolulu Strategy, developed at a NOAA conference in 2011, notes that a more effective solution is to prevent debris from being swept into the oceans in the first place.
But as long as some countries lack the ability to efficiently collect garbage from its citizens, that garbage will continue to end up in the ocean.
Plastic-Making Technology Spreads
Ted Siegler, a partner at DSM Environmental Services, a waste management firm in Windsor, Vermont, has spent a career helping developing countries set up garbage collection systems.
"In many ways, this is really simple. This is putting trucks on the road and picking up the garbage and bringing it to a proper place," he says. "But none of that is occurring in almost all of the places that I've been working in the last 20 years."
The complication, Siegler says, is the speed with which plastic manufacturing technology has spread globally.
"I could walk into a guy's garage in Jordan and he would be blowing film to create plastic bags. Or walk into an industrial shop in Vietnam and a guy would have a brand-new Chinese knockoff of a Frito-Lay packaging machine," he says.
"There is no end in sight to how much plastic we are going to be producing and how much we are going to be using, and that's the scary part. If it's important now, it's going to be much more important ten years from now."
Follow Laura Parker on Twitter.