Explaining the process of EL-Nino, discuss its impact on the Indian monsoon and Agriculture.
(GS-1, Geography, 250 words)
Approach:
- Introduce your answer by describing what is EL-Nino.
- In the body, mention the process of formation of EL-Nino and its impact on the Indian monsoon and agriculture.
- Conclude your answer by providing a way forward.
Model Answer:
El Niño is a climate pattern that describes the unusual warming of surface waters in the eastern tropical Pacific Ocean. El Niño is the “warm phase” of a larger phenomenon called the El Niño-Southern Oscillation (ENSO) and La Niña is its cold phase. It is a complex weather system that appears once every three to seven years, bringing drought, floods and other weather extremes to different parts of the world.
Process of formation of EL-Nino:
- With the onset of El Niño, air pressure falls over the eastern tropical Pacific and rises in the west, with the greatest pressure drop over the central Pacific.
- As the air pressure gradient across the tropical Pacific weakens, trade winds slacken and may even reverse in the west. The see-saw variation in air pressure between the western and central tropical Pacific is known as the Southern Oscillation.
- These changes in air pressure and wind speed cause warm surface water to move eastward along the Equator, from the western Pacific to the coast of northern South America.
- These warm surface waters deepen the thermocline, the level of ocean depth that separates warm surface water from the colder water below.
- This thick layer of warm water does not allow normal upwelling to occur. Without an upwelling of nutrient-rich cold water, the euphotic zone of the eastern Pacific can no longer support its normally productive coastal ecosystem. Fish populations die or migrate.
- This build-up of warm water in the eastern Pacific also transfers heat high into the atmosphere through convection, generating thunderstorms.
Impact of EL-Nino on Indian Monsoon and Agriculture:
- Below average rainfall: Indian monsoon and EL Nino are inversely related to each other. This means El Nino brings the possibility of the Indian monsoon falling below average. About 90 per cent of all evolving El Nino years have led to below-normal rainfall in the country.
- Drought-like conditions: Between 2001 to 2020, the country witnessed seven El Niño years. Out of these, four years led to droughts and this time period also witnessed summer-sown output decline. The phenomenon’s worst impact was seen in 2009-2010 when El Niño resulted in a severe drought in the southern and western regions and significantly delayed rainfall.
- Impact on crop yield: Indian agrarian economy depends heavily on monsoon for good yield. EL Nino directly impacts the agrarian economy as it tends to lower the production of summer crops such as rice, sugarcane, cotton and oilseeds.
- High cost of inputs: Farmers may have to increase their input costs by investing in irrigation, water management, and supplementary feeding for their livestock during droughts caused by El Nino.
- Impact on agriculture workers: A large share of the Indian workforce is employed in agriculture-related work and any impact on crop yields due to deficit rainfall has a direct bearing on these workers.
- Impact on food security and Inflation: Reduced crop production due to below-average rainfall can lead to potential food shortages. Its long-term impact would be on the Indian economy, as a shortage of commodities may lead to a surge in inflation.
- Impact on rural livelihood: The agriculture sector is the primary source of livelihood for almost 55% of India’s population. Drought conditions resulting due to EL Nino are associated with crop failures, yield reductions, and increased input costs, leading to financial losses for farmers.
India can overcome the impact inflicted by El Niño by implementing contingency plans at the district level. Initiatives such as introducing seeds of late sowing variety, water conservation and management, and maintaining natural water bodies can help in transforming the agricultural sector and making it resilient enough to deal with challenges like El Niño.
