Friday, April 16, 2010

Great Pacific Garbage Patch

Also known as the Pacific Trash Vortex, this massive accumulation of marine litter (mostly plastic) is located in the central North Pacific Ocean, approximately between 135 to 155W and 35 to 42N. The exact size of this floating island of garbage is unknown, although estimates range from the size of the state of Texas to one larger than the continental United States. Although the existence of this garbage buildup was predicted in a 1988 NOAA publication, its actual confirmed discovery did not come until 1997 when Charles Moore came across it after the Transpac sailing race. Oceanographers were alerted and gave the region the title "Eastern Garbage Patch" (EGP).

Marine debris has been amalgamating all over the world's oceans, and it is assumed that the Great Pacific Garbage Patch formed by the similar mechanisms: oceanic currents. The garbage patch is located in a seemingly stationary region of the North Pacific Ocean located in the middle of many strong currents. It draws in waste materials from across the entire ocean, including coastal waters off Japan and North America. As debris becomes trapped in the currents, the floating plastic is gradually moved towards the center by wind-driven surface currents. Moore's description of the patch as a massive accumulation of plastic is slightly misleading. The process of disintegration means that the plastic particles in most of the patch are actually too small to be seen. In a 2001 study, researchers found concentrations of plastics to be 334,721 pieces per km squared, with a mean mass of 11.27 lbs per km squared.

As the plastic is disintegrating into smaller and smaller particles, many of them are sinking deep into the ocean and affecting many levels of the food web. These small pieces of toxic-filled plastic have been known to be consumed by jellyfish, which are then eaten by larger fish. Some of the long-lasting larger pieces of plastics are consumed by marine birds and animals, including sea turtles and the albatross.

The initial cleanup steps are now underway as groups are taking samples and attempting to raise awareness of the issue. Make no mistake though, irreversible damage has already been done. Cleaning up the plastic will be a costly and difficult endeavor, one which might be thwarted by a buildup of more plastics likely to be occurring at a faster rate.

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