2. What is El-Nino and La-Nina? Examine their effects on India’s climate.
एल-निनो और ला-नीना क्या है? भारत के जलवायु पर उनके प्रभाव की जांच करें।
This question has broadly two parts. First part demands the explanation of concepts. In first part, again there are two sub parts, El-Nino and La-Nina. The second part demands effects on climate (note that, it is written climate, not monsoon). Start with introduction, then three parts, and then conclude the answer.
- Indian climatic conditions are shaped by many factors; one of them is El-Nino Southern Oscillation (ENSO).
- The El Nino-Southern Oscillation (ENSO) is a recurring climate pattern involving changes in the temperature of waters in the central and eastern tropical Pacific Ocean.
- El Nino and La Nina are the extreme phases of the ENSO cycle.
(Note: These maps are for your understanding. In answer you can draw one map to show both events, with different color pens)
- Phenomenon of warming of the ocean surface, or above-average sea surface temperatures (SST), in the central and eastern tropical Pacific Ocean is known as El Nino.
- The low-level surface winds, which normally blow from east to west along the equator (“easterly winds”), instead weaken or, in some cases, start blowing the other direction (from west to east or “westerly winds”).
- This reversal of winds creates unusual warming and low pressure near the Peruvian Coast, and causes heavy rainfall.
- Phenomenon of cooling of the ocean surface or below-average Sea surface temperatures (SST), in the central and eastern tropical Pacific Ocean is known as La Nina.
- The normal easterly winds along the equator become even stronger.
- This situation causes heavy rainfall (monsoon) on western Pacific areas.
Effects of El-Nino and La-Nina on India’s climate
- For India, El Nino during winter results in development of warm conditions.
- During summer, it leads to dry conditions and deficient monsoon, leading to droughts and water scarcity.
- Whereas La-Nina brings rains and stronger monsoon in India, it may cause flood like situation in coastal areas.
- El-Nino and La-Nina are complex unpredictable phenomenon and Agriculture being the important occupation, climatic changes due to these are grave for India.
- Research and studies has suggested that, El-Nino and La-Nina do not always affect the climate of India severely. Some other ocean atmospheric phenomena such as Indian Ocean dipole also impact the monsoon.
- Climate change has also adversely affected India’s climate. Global and national efforts such as NDCs, if implemented properly, can bring the stability to the fast changing climatic conditions.
Best Answer: Isaac Ali