Garbage patch

Trash washed ashore in Hawaii from the Great Pacific Garbage Patch

A garbage patch is a gyre of marine debris particles caused by the effects of ocean currents and increasing plastic pollution by human populations. These human-caused collections of plastic and other debris are responsible for ecosystem and environmental problems that affect marine life, contaminate oceans with toxic chemicals, and contribute to greenhouse gas emissions. Once waterborne, marine debris becomes mobile. Flotsam can be blown by the wind, or follow the flow of ocean currents, often ending up in the middle of oceanic gyres where currents are weakest.

Within garbage patches, the waste is not compact, and although most of it is near the surface of the ocean, it can be found up to more than 30 metres (100 ft) deep in the water.[1] Patches contain plastics and debris in a range of sizes from Microplastics and small scale plastic pellet pollution, to large objects such as fishing nets and consumer goods and appliances lost from flood and shipping loss.

Garbage patches grow because of widespread loss of plastic from human trash collection systems. The United Nations Environmental Program estimated that "for every square mile of ocean" there are about "46,000 pieces of plastic".[2] The 10 largest emitters of oceanic plastic pollution worldwide are, from the most to the least, China, Indonesia, Philippines, Vietnam, Sri Lanka, Thailand, Egypt, Malaysia, Nigeria, and Bangladesh,[3] largely through the rivers Yangtze, Indus, Yellow, Hai, Nile, Ganges, Pearl, Amur, Niger, and the Mekong, and accounting for "90 percent of all the plastic that reaches the world's oceans".[4][5] Asia was the leading source of mismanaged plastic waste, with China alone accounting for 2.4 million metric tons.[6]

The best known of these is the Great Pacific Garbage Patch which has the highest density of marine debris and plastic. The Pacific Garbage patch has two mass buildups: the western garbage patch and the eastern garbage patch, the former off the coast of Japan and the latter between California and Hawaii. These garbage patches contain 90 million tonnes (100 million short tons) of debris.[1] Other identified patches include the North Atlantic garbage patch between North America and Africa, the South Atlantic garbage patch located between eastern South America and the tip of Africa, the South Pacific garbage patch located west of South America, and the Indian Ocean garbage patch found east of South Africa listed in order of decreasing size.[7]

  1. ^ a b "Marine Debris in the North Pacific A Summary of Existing Information and Identification of Data Gaps" (PDF). United States Environmental Protection Agency. 24 July 2015.
  2. ^ Maser, Chris (2014). Interactions of Land, Ocean and Humans: A Global Perspective. CRC Press. pp. 147–48. ISBN 978-1482226393.
  3. ^ Jambeck, Jenna R.; Geyer, Roland; Wilcox, Chris (12 February 2015). "Plastic waste inputs from land into the ocean" (PDF). Science. 347 (6223): 769. Bibcode:2015Sci...347..768J. doi:10.1126/science.1260352. PMID 25678662. S2CID 206562155. Archived from the original (PDF) on 22 January 2019. Retrieved 28 August 2018.
  4. ^ Christian Schmidt; Tobias Krauth; Stephan Wagner (11 October 2017). "Export of Plastic Debris by Rivers into the Sea" (PDF). Environmental Science & Technology. 51 (21): 12246–12253. Bibcode:2017EnST...5112246S. doi:10.1021/acs.est.7b02368. PMID 29019247. The 10 top-ranked rivers transport 88–95% of the global load into the sea
  5. ^ Franzen, Harald (30 November 2017). "Almost all plastic in the ocean comes from just 10 rivers". Deutsche Welle. Retrieved 18 December 2018. It turns out that about 90 percent of all the plastic that reaches the world's oceans gets flushed through just 10 rivers: The Yangtze, the Indus, Yellow River, Hai River, the Nile, the Ganges, Pearl River, Amur River, the Niger, and the Mekong (in that order).
  6. ^ Robert Lee Hotz (13 February 2015). "Asia Leads World in Dumping Plastic in Seas". Wall Street Journal. Archived from the original on 23 February 2015.
  7. ^ Cózar, Andrés; Echevarría, Fidel; González-Gordillo, J. Ignacio; Irigoien, Xabier; Úbeda, Bárbara; Hernández-León, Santiago; Palma, Álvaro T.; Navarro, Sandra; García-de-Lomas, Juan; Ruiz, Andrea; Fernández-de-Puelles, María L. (2014-07-15). "Plastic debris in the open ocean". Proceedings of the National Academy of Sciences. 111 (28): 10239–10244. Bibcode:2014PNAS..11110239C. doi:10.1073/pnas.1314705111. ISSN 0027-8424. PMC 4104848. PMID 24982135.