Great Pacific Garbage Patch

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The North Pacific Gyre is one of five major oceanic gyres

The Great Pacific Garbage Patch, also known variously as the Plastic soup, the Eastern Garbage Patch, or the Pacific Trash Vortex, is an area of marine debris in the North Pacific Gyre in the central North Pacific Ocean. Size estimates vary from an area equivalent to the state of Texas to double that of the continental United States.

[edit] Phenomenon

The Great Pacific garbage patch has been in the pacific ocean for over 2 decades. The person that had found this patch was Professor Greenberg.^[who?] The center of the North Pacific Gyre is a relatively stationary region of the North Pacific Ocean, an area often referred to as the horse latitudes. The circular rotation around it draws waste material in and has led to the accumulation of flotsam and other debris, so much so that the plastic debris gathers in concentrations of one million pieces of plastic per square mile in some areas. While historically this debris has biodegraded, the gyre is now accumulating vast quantities of plastic and marine debris. Rather than biodegrading, plastic photodegrades, disintegrating in the ocean into smaller and smaller pieces. These pieces, still polymers, eventually become individual molecules, which are still not easily digested.^[1] Some plastics photodegrade into other pollutants.

The gyre is discussed in Alan Weisman's The World Without Us as an example of the near-indestructibility of discarded plastic.

[edit] Impact on wildlife

This Laysan Albatross chick has been fed plastic by its parents and was unable to eject it, resulting in death by either starvation or choking.

The floating particles also resemble zooplankton, which can lead to them being consumed by jellyfish, thus entering the ocean food chain.^[1] In samples taken from the gyre in 2001, the mass of plastic exceeded that of zooplankton (the dominant animal life in the area) by a factor of seven. Many of these long-lasting pieces end up in the stomachs of marine birds and animals,^[2] including sea turtles, and Black-footed Albatross.^[1] Besides ingestion and entanglement of wildlife, the floating debris absorbs toxins in the water which, when ingested, are mistaken by the animal brain for estradiol, causing hormone disruption in the affected wildlife.^[1]

[edit] Characteristics

For several years ocean researcher Charles Moore has been investigating a concentration of floating plastic debris in the North Pacific Gyre. He has reported concentrations of plastics on the order of 3,340,000 pieces/km² with a mean mass of 5.1kg/km² collected using a manta trawl with a rectangular opening of 0.9m x 0.15m at the surface. Trawls at depths of 10m found less than half, consisting primarily of monofilament line fouled with diatoms and other plankton.^[3]

Estimates of the size of the patch varies from the size of Texas^[4] to twice as large as the continental United States.^[5] Researcher Dr. Marcus Eriksen believes the Great Pacific Garbage Patch is two areas of rubbish that are linked. Eriksen says the gyre stretches from about 500 nautical miles off the coast of California, across the Northern Pacific to near the coast of Japan^[6].

The Independent newspaper stated that Moore estimates there are 100 million tons of flotsam in the North Pacific Gyre.^[7]

Much of the plastic is in very small pieces floating under the surface of the water, meaning capturing a photograph of the patch is not possible. Because the garbage is so small and scattered, clean-up is also incredibly difficult, without endangering sea life.^[8]

One of the first researchers to study the Pacific gyre was oceanographer W. James Ingraham Jr. He developed the Ocean Surface Current Simulator (OSCURS) and predicts that objects trapped in the gyre may remain trapped there for sixteen years or more.^[2]

[edit] Sources

Moore estimates that 80% of the garbage comes from land-based sources, and 20% from ships at sea.^[4] He says that currents carry debris from the east coast of Asia to the center of the gyre in a year or less, and debris from the west coast of North America in about five years.^[4]

[edit] Lost cargo

Occasionally, shifts in the ocean currents release flotsam lost from cargo ships into the currents around the North Pacific Gyre, leading to predictable patterns of garbage washing up on the shores around the outskirts of the gyre. The most famous was the loss of approximately 80,000 Nike sneakers and boots from the ship Hansa Carrier in 1990: the currents of the gyre distributed the shoes around the shores of British Columbia, Washington, Oregon, and Hawaii over the following three years. Similar cargo spills have involved 29,000-30,000 plastic bathtub toys (yellow ducks, blue turtles and green frogs) in 1992 and hockey equipment in 1994. These events have become a major source of data on global-scale ocean currents. Institutions have asked the public to report the landfall locations of these objects, such as the trainers and rubber ducks, that wash up as a method of tracking surface waters' response to the deeper ocean currents.^[9][10]

[edit] References

[edit] Further reading

• Oliver J. Dameron, Michael Parke, Mark A. Albins and Russell Brainard (April 2007). "Marine debris accumulation in the Northwestern Hawaiian Islands: An examination of rates and processes", Marine Pollution Bulletin 54 (4), 423-433.

• Floating plastic in the Kuroshio Current area, western North Pacific Ocean — Rei Yamashita and Atsushi Tanimura [Marine Pollution Bulletin; volume 54, issue 4, pages 485-488 (2007)]

• Movement and accumulation of floating marine debris simulated by surface currents derived from satellite data — Masahisa Kubota, Katsumi Takayama and Noriyuki Horii [School of Marine Science and Technology, Tokai University (2000)]

• Pelagic plastics and other seaborne persistent synthetic debris — M R Gregory and P G Ryan [Marine Debris: Sources, Impacts, Solutions; pages 49-66 — J M Coe and D B Rogers (1997)]

• A comparison of plastic and plankton in the North Pacific Central Gyre — Charles J Moore, Shelly L Moore, Molly K Leecaster and Stephen B Weisberg

• Density of plastic particles found in zooplankton trawls from coastal waters of California to the North Pacific Central Gyre — Charles J Moore, Gwen L Lattin and Ann F Zellers

• The quantitative distribution and characteristics of neuston plastic in the North Pacific Ocean, 1984-1988 — R H Day, D G Shaw and S E Ignell (1990)

• Thomas Morton, ‘Oh, This is Great, Humans Have Finally Ruined the Ocean’, Vice Magazine, Vol. 6, No. 2 (2007), pp. 78-81.

[edit] External links

• The trash vortex — Greenpeace
• Navigating the Pacific's 'Garbage Patch' — National Public Radio
• New 'battle of Midway' over plastic — BBC News
• Marine Research, Education and Restoration — Algalita Marine Research Foundation
• Humans Have Finally Ruined the Ocean — Vice Magazine
• Diary from the middle of nowhere — BBC News
• Trashed: Across the Pacific Ocean, Plastics, Plastics, Everywhere — Natural History
• Images & video from the North Pacific gyre — WordPress.com
• The plastic killing fields — The Sydney Morning Herald.
• Real time blogging from the North Pacific Gyre — The Beagle Project
• The Largest Garbage Dump on Earth — Literary Escorts Services
• Garbage Island — CNN Headline News — "News to Me"

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