El Niño
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S: http://www.un.org/apps/news/story.asp?NewsID=53790#.V3vuMZOLRuU (last access: 5 July 2016); http://www.livescience.com/3650-el-nino.html (last access: 5 July 2016); https://www.climate.gov/enso (last access: 5 July 2016).

N: 1. Since the 16th century, Spanish colonists in South America had written about these años de abundancia, when torrential rains made the desert bloom. They called it El Niño, after the baby Jesus, since the strange currents tended to arrive around Christmas. Years of abundance onshore brought devastation to the oceans: the anchovy fishery, a staple of the Peruvian economy, collapsed, as fish died or fled in search of colder waters. Fish-eating seabirds starved in droves.
2. An anomalous warming of ocean water off the west coast of South America, usually accompanied by heavy rainfall in the coastal region of Peru and Chile.
3. An anomalous warming of ocean water resulting from the oscillation of a current in the South Pacific, usually accompanied by heavy rainfall in the coastal region of Peru and Chile, and reduction of rainfall in equatorial Africa and Australia. (UN DHA)
4. El Niño-Southern Oscillation: The term El Niño was initially used to describe a warm-water current that periodically flows along the coast of Ecuador and Perú, disrupting the local fishery. It has since become identified with a basin-wide warming of the tropical Pacific Ocean east of the dateline. This oceanic event is associated with a fluctuation of a global-scale tropical and subtropical surface pressure pattern called the Southern Oscillation. This coupled atmosphere-ocean phenomenon, with preferred time scales of two to about seven years, is collectively known as the El Niño-Southern Oscillation (ENSO). It is often measured by the surface pressure anomaly difference between Darwin and Tahiti and the sea surface temperatures in the central and eastern equatorial Pacific. During an ENSO event, the prevailing trade winds weaken, reducing upwelling and altering ocean currents such that the sea surface temperatures warm, further weakening the trade winds. This event has a great impact on the wind, sea surface temperature and precipitation patterns in the tropical Pacific. It has climatic effects throughout the Pacific region and in many other parts of the world, through global teleconnections. The cold phase of ENSO is called La Niña.

S: 1. http://baynature.org/article/whys-it-called-el-nino-and-how-did-scientists-figure-out-what-it-is/ (last access: 5 July 2016). 2. METEOTERM – International Meteorological Vocabulary, WMO – No. 182 (last access: 5 July 2016). 3. http://reliefweb.int/sites/reliefweb.int/files/resources/4F99A3C28EC37D0EC12574A4002E89B4-reliefweb_aug2008.pdf (last access: 5 July 2016). 4. METEOTERM – IPCC 4th Assessment Report, WG 1 Glossary (last access: 5 July 2016).

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CR: environmental refugees, La Niña, meteorology.