El Niño related health hazards in India

The term El Niño (means Christ child in Spanish) was originally used by fishermen along the coasts of Ecuador and Peru to refer to a warm ocean current that typically appears around Christmas time and lasts for several months. Fish are less abundant during these warm intervals, so fishermen often take a break to repair their equipment and spend time with their families. Over the years, the term ‘El Niño’ is referred to these exceptionally strong warm intervals that not only disrupt the normal lives of the fishermen, but also bring heavy rains. El Niño phenomenon (current) was first observed by the German explorer/geographer and naturalist Alexander von Humboldt (1769–1859). The Humboldt Current was named after him. In a letter dated 18 September 1839, Humboldt wrote to Charles Darwin as follows: ‘. . .I wished to tell you still more about this running cold water which runs alongside the Peru of which I am very concerned, believing that it will much modify the climate of the littoral. . .’. The cool Humboldt Current flows north along the west coast of South America. It is part of the anti-clockwise flow of the South Pacific gyre, a circular current on the ocean’s surface. As the wind and current push seawater away from the coast, upwelling occurs, which allows cool, deep, nutrient-rich waters to rise to the sunlit zones. This, in turn, creates a food-rich marine environment that includes penguins and sea lions, and productive fishing grounds. The cool upwelling also produces fog, but little rainfall in the desert coasts of Peru and northern Chile. Occasionally, the pattern is broken, the upwelling stops and is overridden by warm tropical waters from the central Pacific. This reversal of marine temperature conditions is known as El Niño. This causes great loss of marine life and changes conditions from dry and desert-like to stormy and humid. On rare occasions, such as in 1982 and 1983, a prolonged El Niño may extend beyond the Humboldt Current region to as far north as California and as far south as the Antarctic. Table 1 shows the El Niño events which were noted during the 20th century. When El Niño event occurs, there is a decline in the production of plankton which has repercussions on fish and sea bird populations.