El Niño, a 13 Per Cent Monsoon Deficit and the Limits of IMD Forecasting

The India Meteorological Department (IMD) announced on September 30 that the monsoon tally ended at 759 mm across the country, which is 87 per cent of the normal 869 mm. The shortfall of around 12 to 13 per cent comes in an El Niño year, when warming of the Central Equatorial Pacific suppresses monsoon rains. The IMD’s April and May forecasts had predicted “below normal” rain of 90 to 95 per cent of the long period average (LPA), although its models pointed to a “deficient” outcome below 90 per cent.

An editorial in The Hindu notes that the IMD can claim technical success because the final figure falls within its 4 to 5 per cent error window, but that its record on magnitude at disaggregated levels is weaker. The agency expected a “normal” monsoon in the northeast, which instead recorded its driest season since 1901, with a 26 per cent shortfall. The south peninsula was 23 per cent short.

The consequences are already visible. Karnataka has declared drought in well over 100 taluks and Maharashtra in 265 of 358 taluks, though the national deficit is below the Centre’s 20 per cent threshold for “agricultural drought”. With the IMD expecting El Niño to strengthen and rainfall to remain below normal over most of the country from October to December, soil moisture and reservoir recharge are at risk.

Background and Context

Five Important Key Points

• The monsoon ended at 759 mm, which is 87 per cent of the normal 869 mm.
• The IMD forecast “below normal” rain (90 to 95 per cent of LPA), though its models suggested “deficient” rain.
• June rainfall was 65 per cent of normal against a forecast of 92 per cent, while August was 84 per cent.
• The northeast recorded its driest monsoon since 1901 (26 per cent short), and the south peninsula was 23 per cent short.
• Karnataka has declared drought in over 100 taluks and Maharashtra in 265 of 358, and the Cabinet raised wheat’s MSP by ₹25 and mustard’s by ₹413 per quintal.

Understanding El Niño and the Monsoon

El Niño is the warm phase of the El Niño-Southern Oscillation. When the central and eastern Pacific warms, the Walker circulation weakens, subsidence over the Indian region increases, and monsoon rainfall tends to fall. The effect can be modulated by the Indian Ocean Dipole and by mid-latitude Western Disturbances. The editorial notes that Western Disturbances have been bringing more rain to India during monsoon months, while southern India appears more vulnerable to El Niño-triggered volatility, which complicates forecasts.

Forecasting Capacity and Institutional Issues

The IMD uses a mix of statistical and dynamical models, and the government launched Mission Mausam in 2024 to upgrade observation networks, supercomputing and high-resolution forecasting. The critique is that national-level accuracy hides large regional and monthly errors. Farmers and State governments need sub-regional, district-level forecasts. The agency also faces a communication challenge: hedged categories like “below normal” may understate risk, when a clear warning of “deficiency” would have prompted earlier preparation.

Agricultural and Economic Impact

Kharif sowing trailed the previous year by 16 per cent in early July, narrowing to under 2 per cent by early September. Yet below-normal rains during October to December threaten the rabi crop, which relies on soil moisture and reservoir storage. The Cabinet’s increase in wheat and mustard minimum support prices is intended to nudge diversification and sustain incomes. A poor monsoon can lift food inflation, strain rural demand and increase the demand for MGNREGA-style work. Rural wages and GST consumption in agrarian States are also affected.

Disaster Management and Legal Framework

Drought is managed through the Manual for Drought Management (2016), under which States declare drought on the basis of rainfall deficiency, dry spells, vegetation indices and sowing data. Relief is financed through the State Disaster Response Fund and the National Disaster Response Fund, under the Disaster Management Act, 2005. Crop losses are covered by the Pradhan Mantri Fasal Bima Yojana. The National Disaster Management Authority coordinates preparedness.

Bihar Connection

Bihar is overwhelmingly dependent on the kharif season, especially paddy, and frequently faces paradoxical conditions: floods in north Bihar from Himalayan rivers such as the Kosi and Gandak, and deficient rainfall in the south. In 2022, rainfall deficiency affected many districts and exposed vulnerabilities in paddy transplantation and irrigation. Bihar’s responses include the Jal-Jeevan-Hariyali Abhiyan, state tube-well schemes and a crop diversification focus in its Agriculture Road Maps. A strengthening El Niño in October to December could hurt rabi crops such as wheat and pulses in Bihar, so district-level contingency plans and seed availability are important.

Climate Change and Comparative Perspective

Climate change makes variability more complex. Australia and Southeast Asia also face El Niño-linked droughts, and Australia’s Bureau of Meteorology issues seasonal outlooks with probabilistic categories. India’s approach could shift towards probabilistic and impact-based forecasts that tell users the likelihood of deficits, not only a category.

Way Forward

India should expand dense observation networks and invest in high-resolution district-level models under Mission Mausam. The IMD should issue probabilistic, impact-based advisories. States should prepare contingency plans, promote drought-resilient crops such as millets and pulses, and support micro-irrigation under the Pradhan Mantri Krishi Sinchayee Yojana. Insurance claims under PMFBY must be settled quickly. Reservoir management should be dynamic, with early warnings to farmers about rabi sowing.

Relevance for UPSC and SSC Examinations

UPSC: GS-I (monsoon, climatology, El Niño), GS-III (agriculture, disaster management, food security, environment), Essay (climate and agrarian distress).
SSC: Monsoon onset, normal rainfall, IMD headquarters, El Niño, MSP, PMFBY.
Key terms: El Niño, LPA, Indian Ocean Dipole, Western Disturbances, Mission Mausam, Drought Manual 2016, SDRF/NDRF, PMFBY, MSP.