Question

Explain the ENSO(EI Nino-Southern Oscillation) and its effects on Indian Climate.

Answer 1

El Nino and La Nina are among the most powerful phenomenon on the Earth. These are known to alter climate across more than half the planet and dramatically impact weather patterns.El nino (which meansin spanish as the christ child as this event takes place during christmas ) is a warm ocean current that flows along the equator from the date line and south off the coast of Ecuador at Christmas time and La Nina (which means the little girl) is a cold event or a cold episode of cooling the water in the eastern pacific ocean. Both El Nino and La Nina are part of a larger cycle called ENSO, or El Niño–Southern Oscillation. The El Niño (warm event) and La Nina (Cold event) both have now established themselves as the integral part of the global climate system.

Over Indian subcontinent, El Nino during winter results in development of warm conditions. During summer, it leads to dry conditions and deficient monsoon. It also leads to drought in Australia. On the other hand, La Nina results in better than normal monsoon in India. At the same time, in Australia it has caused floods.

In the recent past, India experienced deficient rainfall during El Nino years 2002 and 2009 whereas monsoon was normal during El Nino years 1994 and 1997. This so far implies that in about 50 per cent of the years with El Nino during summer, India experienced droughts during monsoon.

This implies that El Nino is not the only factor that affects monsoon in India. There are other factors that affect India’s rainfall pattern. These include North Atlantic SST, Equatorial SE Indian Ocean SST, East Asia Mean Sea Level Pressure, North Atlantic Mean Sea Level Pressure and North Central Pacific wind at 1.5 km above sea level.