Trashed: across the Pacific Ocean, plastics, plastics, everywhere

Natural History, Nov, 2003 by Charles Moore

It was on our way home, after finishing the Los Angeles-to-Hawaii sail race known as the Transpac, that my crew and I first caught sight of the trash, floating in one of the most remote regions of all the oceans. I had entered my cutter-rigged research vessel, Alguita, an aluminum-hulled catamaran, in the race to test a new mast. Although Alguita was built for research trawling, she was also a smart sailor, and she fit into the "cruising class" of boats that regularly enter the race. We did well, hitting a top speed of twenty knots under sail and winning a trophy for finishing in third place.

Throughout the race our strategy, like that of every other boat in the race, had been mainly to avoid the North Pacific subtropical gyre--the great high-pressure system in the central Pacific Ocean that, most of the time, is centered just north of the racecourse and halfway between Hawaii and the mainland. But after our success with the race we were feeling mellow and unhurried, and our vessel was equipped with auxiliary twin diesels and carried an extra supply of fuel. So on the way back to our home port in Long Beach, California, we decided to take a shortcut through the gyre, which few seafarers ever cross. Fishermen shun it because its waters lack the nutrients to support an abundant catch. Sailors dodge it because it lacks the wind to propel their sailboats.

I often struggle to find words that will communicate the vastness of the Pacific Ocean to people who have never been to sea. Day after day, Alguita was the only vehicle on a highway without landmarks, stretching from horizon to horizon. Yet as I gazed from the deck at the surface of what ought to have been a pristine ocean, I was confronted, as far as the eye could see, with the sight of plastic.

It seemed unbelievable, but I never found a clear spot. In the week it took to cross the subtropical high, no matter what time of day I looked, plastic debris was floating everywhere: bottles, bottle caps, wrappers, fragments. Months later, after I discussed what I had seen with the oceanographer Curtis Ebbesmeyer, perhaps the world's leading expert on flotsam, he began referring to the area as the "eastern garbage patch." But "patch" doesn't begin to convey the reality. Ebbesmeyer has estimated that the area, nearly covered with floating plastic debris, is roughly the size of Texas.

My interest in marine debris did not begin with my crossing of the North Pacific sub-tropical gyre. Voyaging in the Pacific has been part of my life since earliest childhood. In fifty-odd years as a deckhand, stock tender, able seaman, and now captain, I became increasingly alarmed by the growth in plastic debris I was seeing. But the floating plastics in the gyre galvanized my interest.

I did a quick calculation, estimating the debris at half a pound for every hundred square meters of sea surface. Multiplied by the circular area defined by our roughly thousand-mile course through the gyre, the weight of the debris was about 3 million tons, comparable to a year's deposition at Puente Hills, Los Angeles's largest landfill. I resolved to return someday to test my alarming estimate.

Historically, the kind of drastic accumulation I encountered is a brand-new kind of despoilment. Trash has always been tossed into the seas, but it has been broken down in a fairly short time into carbon dioxide and water by marine microorganisms. Now, however, in the quest for lightweight but durable means of storing goods, we have created a class of products--plastics--that defeat even the most creative and voracious bacteria.

Unlike many discarded materials, most plastics in common use do not biodegrade. Instead they "photodegrade," a process whereby sunlight breaks them into progressively smaller pieces, all of which are still plastic polymers. In fact, the degradation eventually yields individual molecules of plastic, but these are still too tough for most anything--even such indiscriminate consumers as bacteria--to digest. And for the past fifty years or so, plastics that have made their way into the Pacific Ocean have been fragmenting and accumulating as a kind of swirling sewer in the North Pacific subtropical gyre.

It surprised me that the debris problem in the gyre had not already been looked at more closely by the scientific community. In fact, only recently--starting in the early 1990s--has the scientific community begun to focus attention on the trash in the gyre. One of the first investigators to study the problem was W. James Ingraham Jr., an oceanographer at the National Oceanic and Atmospheric Administration (NOAA) in Seattle. Ingraham's Ocean Surface Current Simulator (OSCURS) predicts that objects reaching this area might revolve around in it for sixteen years or more [see illustrations on opposite page].

A year after my sobering voyage, I asked Steven B. Weisberg, director of the Southern California Coastal Water Research Project and an expert in marine environmental monitoring, to help me make a more rigorous estimate of the extent of the debris in the subtropical gyre. Weisberg's group had already published an article on the debris they had collected in fish trawls of the Southern California Bight, a region along the Pacific coast extending a hundred miles both north and south of Los Angeles. As I discussed the design plan for our survey with Weisberg's statisticians, Molly K. Leecaster and Shelly L. Moore, it became apparent that we were facing a new problem. In the coastal ocean, bodies of water are naturally defined, in part, by the coasts they lie against. In the open ocean, however, bodies of water are bounded by atmospheric pressure systems and the currents those systems create. In other words, air, not land, defines the body of water. Because air pressure systems move, the body of water we wanted to survey would be moving as well. A random sample of a moving area such as the gyre would have to be done quite differently from the way Weisberg's group had conducted their survey along the Pacific coast.