Model Answer

El Niño is the abnormal warming of the central and eastern equatorial Pacific associated with weakening trade winds and altered Walker Circulation. NOAA projects over 90% probability of a very strong El Niño during late 2026, making its impacts particularly significant.

How El Niño develops

1. Easterly trade winds weaken across the equatorial Pacific. e.g: Warm surface water shifts eastward towards South America.
2. Eastern Pacific sea-surface temperatures rise abnormally. e.g: Niño-3.4 index monitors ENSO intensity.
3. Upwelling of cold nutrient-rich water weakens along South America. e.g: Peru-Ecuador coast.
4. Walker Circulation shifts eastward, reorganising tropical convection and rainfall.
5. Ocean-atmosphere feedback reinforces warming. e.g: Bjerknes feedback.

Implications for the Indian monsoon

1. El Niño generally weakens monsoon circulation over India. e.g: Subsidence over the Indian subcontinent can suppress rainfall.
2. Rainfall deficiency increases drought probability. e.g: Several major Indian droughts have coincided with El Niño.
3. Monsoon distribution can become spatially and temporally erratic. e.g: Longer break-monsoon conditions.
4. Other climate drivers can moderate its impact. e.g: Positive Indian Ocean Dipole may partly offset El Niño.
5. El Niño does not automatically produce drought. e.g: ENSO-monsoon relationship is probabilistic, not deterministic.

Wider economic and environmental implications

1. Lower rainfall can reduce agricultural output. e.g: Rain-fed pulses and oilseeds.
2. Food shortages can increase inflationary pressures.
3. Reservoir depletion affects irrigation and hydropower generation.
4. Higher temperatures intensify heatwaves and electricity demand.
5. Global climatic disruptions affect commodity prices and food security.

Way Forward

1. Strengthen IMD's seasonal forecasting and district-level climate advisories.
2. Expand drought-resilient crops, micro-irrigation and contingency crop planning.
3. Use reservoir management, food buffers and early-warning systems for anticipatory action.

El Niño is a recurring natural phenomenon, but climate vulnerability magnifies its socioeconomic consequences. Forecast-based preparedness and climate-resilient agriculture can convert improved ENSO prediction into effective risk reduction.