Top 10 Must Read Topics for IAS Mains GS Paper 1 | Effects of EL Nino and La Nina on Monsoon: IAS is a dream opportunity for all the people looking for a secure and reputed job with the responsibility of serving the nation. Union Public Services Commission conducted the IAS Prelims exam on 18 June 2017.
All the UPSC IAS aspirants are now preparing for IAS Mains 2017. The problem is that no matter how good & knowledgeable we think we are or how good we feel we have prepared for the exam there is always a certain level of uncertainty. To overcome this fear, we will be sharing Top 10 Must Read Topics for IAS Mains GS Paper 1.
Top 10 Must Read Topics for IAS Mains GS Paper 1 | Effects of EL Nino and La Nina on Monsoon
Today we will discuss the Next Topic. Below mentioned is the explanation of the said topic.
What is EL Nino
El Niño is a climate cycle in the Pacific Ocean with a global impact on weather patterns. The cycle begins when warm water in the western tropical Pacific Ocean shifts eastward along the equator toward the coast of South America. Normally, this warm water pools near Indonesia and the Philippines.
What is La Nina
La Niña is also sometimes called El Viejo, anti-El Niño, or simply “a cold event.” La Niña episodes represent periods of below-average sea surface temperatures across the east-central Equatorial Pacific. Global climate La Niña impacts tend to be opposite those of El Niño impacts.
Effects of EL Nino and La Nina on Monsoon
- Generally, El Nino and the Indian Monsoon rains are inversely related. Trade winds coming from South America normally blow westward towards Asia during Southwest Monsoon. Warming of the Pacific Ocean results in weakening of these winds. Therefore, moisture and heat content gets limited and results in reduction and uneven distribution of rainfall across the Indian sub-continent.
- The effect an El Nino has on India is probabilistic in nature. Statistically, there are 40% chances that an El Nino will result in a drought situation in India. It implies an El Nino doesn’t necessarily result in a drought in India. For example in 1997, an El Nino year, India witnessed an above average rainfall and there are many other years in which an El Nino did not result in a drought in India. So, an El Nino in isolation cannot have a definitive effect on India.
- La-Nina basically is one side of ENSO cycle which is a typical ocean temperature and atmosphere interaction resulting in climatic aberrations. La-Nina is the piling up of cold water near the West Coast of South America or shifting of warm currents towards the West Pacific or the Indonesian region as a result this aggravates the atmosphere of India and results in strong monsoon. La-Nina strengthens the monsoon or even can bring in high rains and storms. La-Nina is just like a healthy monsoon season with stronger approach.