Published By: Ishani Karmakar

The Impact Of El Nino Every One Is Talking About

The El Nino and La Nina phases of the El Nino-Southern Oscillation (ENSO) cycle are opposed. The El Nino Southern Oscillation (ENSO) is a recurrent climatic phenomenon characterized by shifts in sea surface temperature, upper and lower-level wind patterns, sea-level pressure, and the distribution of tropical rainfall over the Pacific Ocean and its surrounding waters. El Nino is the common name for ENSO while it is in its warm phase, whereas La Nina is the common name for it when it is in its cold phase. These temperature departures from the norm at the Earth's surface may have a significant effect on the world's climate and weather.

Learn about La Nina and El Nino and how they affect the climate in India.

El Nino Significance

El Nino translates to "little boy" or "Christ child" in Spanish. This term was given to the phenomena since the fisherman first saw it in South America in the early 17th century. For this reason, December was chosen to represent the warming trend of the Pacific Ocean's waters. El Nino occurs when sea surface temperatures in the central and east-central Equatorial Pacific rise above average and remain there for an extended period. This is the result of a large-scale interaction between the ocean and the atmosphere. The cause may be traced back to the high pressure seen in the western Pacific. As a result, the El Nino effect has had a destructive impact on Indian monsoons and, by extension, Indian agriculture.

Scientists have shown that El Nino and the Southern Oscillation co-occur in the 1930s, thanks to the research of Sir Gilbert Walker. When coastal waters in the eastern tropical Pacific become warmer, the air pressure above the ocean drops (El Nino). Climatologists call the relationship between El Nio and the Southern Oscillation "El Nino-Southern Oscillation" (ENSO). Most professionals in the field now refer to El Nio and ENSO as "El Nio" and "ENSO" respectively.

Effect of El Nino on India

The pressure is distributed in a regular (non-El Nino) monsoon year. Northern Australia and Southeast Asia have lower pressure than the coast of Peru in South America.

The Indian Ocean has lower pressure than the other oceans because it is warmer than they are. Hence, rain winds move from the western Pacific to the Indian Ocean. As the continent of India has a lower pressure than the Indian Ocean, winds carrying moisture from the sea can travel further inland. If the average pressure distribution is altered, the monsoons will be affected.

El Nino warms cold surface water off the coast of Peru. The typical trade winds die out or change directions when the water gets too warm. This causes winds carrying rain and cloudiness from the western Pacific to be channeled toward the coast of Peru (the region near northern Australia and South East Asia). During an El Nino, it causes heavy precipitation in Peru but prevents the usual monsoon rains from reaching the Indian subcontinent. When there is a significant difference in temperature and pressure, there is also a substantial difference in the amount of rainfall that falls in India.

Climate Change in India Due to El Nino and La Nina

The Indian subcontinent has dry conditions and a weak monsoon when El Nino occurs in the summer. La Nina, on the other hand, results in an exceptional monsoon in India. While the monsoon was usual in El Nino years 1994 and 1997, it was scarce in El Nino years 2002 and 2009. It indicates that India had monsoon droughts for about half of the year, owing to El Nino in the summer. Damage from El Nino will be seen by farmers that grow paddy, maize, peanuts, guar, castor, tur, moong, and bajra.

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