Wednesday, July 16, 2014


The year 2014 could be an El Niño year, which would trigger a poor Monsoon in India. And as we enter mid-April, these observations are turning out to be more accurate. Other meteorological agencies across the world are also very strongly pointing towards the likelihood of an El Niño weather pattern this year.
According to a media report, the US National Oceanic and Atmospheric Administration has suggested increase in chances of an El Niño weather by over 50%, while the Australian Meteorological Bureau has put it at over 70%, further strengthening Skymet’s prediction of an El Niño year.
Though, this system will affect the weather worldwide, countries like India that are largely dependent on Monsoon rain will bear the maximum brunt of it.
Having said that, here's a look into what is this phenomenon and how is it going to impact Monsoon in India.
What is El Niño
El Niño, meaning “little boy” in Spanish, is a weather system which re-emerges after a gap of about 3 to 5 years in the Pacific Ocean and lasts for about 12 months on an average. During this time the warming of sea surface temperatures take place, affecting wind patterns and thus possibly triggering both floods and droughts in different parts of the world.
This phenomenon affects rainfall in India during Monsoon. Due to more heating, warm waters off eastern coast of South America increase the sea surface temperatures above normal by 0.5oC and leads to diversion of flow of moist winds from the Indian Ocean towards the eastern coast of South America. This change in wind pattern reduces the amount of rainfall in the Indian sub-continent.
Impact of El Niño
El Niño and the Indian summer Monsoon are inversely related. The most prominent droughts in India – six of them - since 1871 have been El Niño droughts, including the recent ones in 2002 and 2009.
It is, however, important to note that not all El Niño years lead to drought in India. For instance, 1997-98 was a strong El Niño year but that did not cause drought in India. On the other hand, a moderate El Niño in 2002 resulted in one of the worst droughts in India.
According to Historical data of 126 years (1880-2005), about 90% of all evolving El Niño years have lead to below normal rainfall and 65% of evolving El Niño years have brought droughts. However, one thing is clear that El Niño years do affect the weather in India in terms of Monsoon rain. During this time, the rainfall is generally below normal, which has its bearing on crop production.
What is La Niña
During La Niña, which is just the opposite of El Niño, less heating leads to colder sea waters off western South America coast, thus making it a high pressure zone which pushes the moist sea winds towards the Indian Ocean therefore, increasing chances of normal or excessive rainfall in the Indian sub-continent.
Here is a table showing the records of El Niño and La Niña years in the last decade.
2004El NinoDrought-12%
2007La NinaExcess+10%
2008La NinaAbove normal+5%
2009El NinoSevere Drought-21%
2010La NinaNormal0%
2011La NinaNormal+4%
2012Mild El NinoBelow Normal-8%
2013NeutralAbove Normal+6%
El Niño years directly impact India’s agrarian economy as their effect tends to lower the production of summer crops such as rice, sugarcane and oilseeds. This in return causes inflation to surge and lowers the Gross Domestic Product (GDP). India is the second largest producer of rice and wheat in the world.
Here is a list of droughts taken place in India in last two centuries. Some of these have been an outcome of the El Niño phenomenon.
PeriodDrought YearsNumber of Drought
1801-18301801, 1804, 1806, 1812, 1819, 18256
1831-18601832, 1833, 1837, 1853, 18605
1861-18901862, 1866, 1868, 1873, 1877, 18836
1891-19201891, 1897, 1899, 1901, 1904, 1905, 1907, 1911, 1918, 192010
1921-19501939, 19412
1951-19801951, 1965, 1966, 1968, 1971, 1972, 1974, 19798
1981-20101982, 1986, 1987, 2002, 2004, 20096

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