In the broad expanse of the northern Pacific Ocean, there exists the North Pacific Subtropical Gyre, a slowly moving, clockwise spiral of currents created by a high-pressure system of air currents. The area is an oceanic desert, filled with tiny phytoplankton but few big fish or mammals. Due to its lack of large fish and gentle breezes, fishermen and
sailors rarely travel through the gyre. But the area is filled with something besides plankton: trash, millions of pounds of it, most of it plastic. It's the largest landfill in the world, and it floats in the middle of the ocean.
The gyre has actually given birth to two large masses of ever-accumulating trash, known as the Western and Eastern Pacific Garbage Patches, sometimes collectively called the Great Pacific Garbage Patch. The Eastern Garbage Patch floats between Hawaii and California; scientists estimate its size as two times bigger than Texas [source:LA Times]. The Western Garbage Patch forms east of Japan and west of Hawaii. Each swirling mass of refuse is massive and collects trash from all over the world. The patches are connected by a thin 6,000-mile long current called the Subtropical Convergence Zone. Research flights showed that significant amounts of trash also accumulate in the Convergence Zone.
The garbage patches present numerous hazards to marine life, fishing and tourism. But before we discuss those, it's important to look at the role of plastic. Plastic constitutes 90 percent of all trash floating in the world's oceans [source: LA Times]. The United Nations Environment Program estimated in 2006 that every square mile of ocean hosts 46,000 pieces of floating plastic [source: UN Environment Program]. In some areas, the amount of plastic outweighs the amount of plankton by a ratio of six to one. Of the more than 200 billion pounds of plastic the world produces each year, about 10 percent ends up in the ocean [source:Greenpeace]. Seventy percent of that eventually sinks, damaging life on the ocean floor [source:Greenpeace]. The rest floats; much of it ends up in gyres and the massive garbage patches that form there, with some plastic eventually washing up on a distant shore.
See film: Great Pacific Garbage Patch
In 1997, while returning to southern California after finishing the Los Angeles-to-Hawaii Transpac sailing race, he and his crew caught sight of trash floating in the North Pacific Gyre, one of the most remote regions of the ocean. He wrote articles about the extent of this garbage, and the effects on sea life, which attracted significant attention in the media. “As I gazed from the deck at the surface of what ought to have been a pristine ocean,” Moore later wrote in an essay for Natural History, “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.” An oceanographic colleague of Moore’s dubbed this floating junk yard “the Great Pacific Garbage Patch”
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