🗞️ Why in News India’s winter 2025-26 was 60% below normal rainfall — one of the driest on record — driven by weakened Western Disturbances. March brought an abrupt transition directly from winter to summer, skipping spring almost entirely. Research scientist Akshay Deoras (University of Reading/National Centre for Atmospheric Science, UK) warns in Down to Earth that Pacific Ocean heat accumulation points to El Niño development with 80%+ probability in 2026 — raising serious concerns for India’s Kharif monsoon season.
What Is Happening — The Seasonal Anomaly
Winter 2025-26 (November 2025 – February 2026):
- Rainfall deficit: ~60% below normal across most of India
- Cause: Weakened Western Disturbances (WDs) — the extra-tropical weather systems that bring winter rain to northwest India and snowfall to the Himalayan ranges
March 2026:
- Despite a brief rain event on the spring equinox (March 20), the overall March pattern shows an abrupt jump from winter conditions to pre-summer heat — spring compressed to near-invisibility
- Delhi’s March 20 rain was anomalous; the broader trend is unusually early summer temperatures
What this means:
- Himalayan snowpack deficit: Less WD activity = less snowfall in the Himalayas = reduced spring snowmelt = lower river flows by May–June in the Indus, Ganga, and Brahmaputra systems
- Groundwater recharge gap: Rabi crop irrigation has drawn more heavily on groundwater without adequate winter recharge
- Agricultural calendar compression: Rabi harvest being followed by heat-wave conditions earlier than normal — affecting wheat quality (heat stress at grain-filling stage)
El Niño — What It Is and Why It Matters for India
El Niño is part of the ENSO (El Niño-Southern Oscillation) cycle — a periodic warming of central and eastern Pacific Ocean surface temperatures:
| Phase | Pacific SST | India Impact |
|---|---|---|
| El Niño (warm phase) | Above-average SSTs in central/east Pacific | Suppresses Indian monsoon; drought risk |
| La Niña (cool phase) | Below-average SSTs | Strengthens Indian monsoon; flood risk |
| ENSO Neutral | Near-average SSTs | Variable; other factors dominate |
Why El Niño weakens India’s monsoon:
- The Walker Circulation (atmospheric east-west convection) is disrupted by warm Pacific SSTs
- Upward motion over the Pacific weakens the Arabian Sea low-pressure systems that drive monsoon rainfall toward India
- The monsoon onset is typically delayed; active phases are shorter; break phases are longer
Historical Indian monsoon-El Niño correlation:
- Not every El Niño year is a drought — correlation is ~0.6 (strong but not deterministic)
- Major El Niño years with significant Indian drought: 1972, 1982, 1987, 1997-98, 2002, 2009, 2014-15
- However: 2015-16 (super El Niño) — India’s monsoon was below normal but not catastrophic; evidence that the relationship has weakened somewhat, possibly due to Indian Ocean warming counteracting Pacific influences
The 2026 El Niño Signal — How Serious?
Down to Earth’s analysis of Akshay Deoras’ research:
- NOAA probability: >80% likelihood of El Niño developing in the May–August 2026 window
- Strong El Niño probability: ~1 in 3 (33%)
- Pacific signal comparison: Current subsurface heat accumulation is “relatively stronger and more coherent” than comparable stages in 2023, 2018, 2015, and 2014 — years that all developed into El Niño events
- Onset timing: If El Niño develops by June, it coincides directly with India’s monsoon onset period (June 1 Kerala onset target)
Key monitoring indices:
- Niño 3.4 region SST anomaly: Primary El Niño measurement — the central Pacific (5°N–5°S, 170°W–120°W); El Niño declared when 3-month average anomaly ≥+0.5°C
- SOI (Southern Oscillation Index): Atmospheric component; sustained negative SOI confirms El Niño
- Oceanic Niño Index (ONI): NOAA’s preferred measure; 3-month rolling average of Niño 3.4 SST anomaly
India’s Monsoon Dependence — The Stakes
| Parameter | Data |
|---|---|
| Agriculture’s share of India’s GDP | ~15% |
| Agricultural workforce share | ~44% of employed population |
| Rain-fed agriculture | ~51% of net sown area (no irrigation) |
| Kharif crops dependent on monsoon | Rice, maize, jowar, bajra, soybean, cotton, pulses |
| India’s food grain production (FY25) | ~330 million tonnes (record) |
| Reservoir storage level (March 2026) | Below 10-year average due to dry winter |
Why a deficient monsoon cascades:
- Food production fall → inflation in food prices (already elevated at ~6.2% in Feb 2026)
- Groundwater stress → drinking water crisis in Maharashtra, Rajasthan, Gujarat, Karnataka
- Hydropower deficit → power shortages in south India (major hydro-dependent states: Karnataka, Kerala, Andhra Pradesh, Himachal)
- Kharif income loss → rural demand contraction → broader slowdown
- Fiscal pressure → MGNREGS expansion, drought relief spending
The Editorial’s Core Argument
Down to Earth argues that India is entering its most serious monsoon risk window in several years — and that preparation must begin now, not after the monsoon onset:
1. Reservoir Management
Pre-position water reserves. The current below-normal reservoir storage (following the dry winter) means India enters the pre-monsoon period with less buffer than usual. Inter-basin water transfer preparedness should be activated for drought-prone districts.
2. Agricultural Contingency Planning
The National Contingency Crop Planning mechanism (under ICAR and State Agriculture Departments) must be activated:
- Identify drought-resistant Kharif varieties (for key states) for rapid seed distribution
- Revise sowing calendars and advisory packets
- Advance procurement of food grain buffer stocks for PDS to hedge against price spikes
3. PMFBY Review
PM Fasal Bima Yojana (PMFBY) — India’s crop insurance scheme — needs:
- Rapid claim settlement mechanisms pre-positioned
- Coverage gaps for small/marginal farmers in rain-fed areas addressed before Kharif
- Tech-enabled crop loss assessment (satellite imagery) pre-authorised to avoid delays
4. Heat Action Plans
Compressed spring = early and more intense heat wave season. National Disaster Management Authority (NDMA) heat action plans must be activated for high-risk cities (Ahmedabad, Nagpur, Bhubaneswar, Lucknow) earlier than the normal April-May window.
Western Disturbances — The Mechanism
Western Disturbances (WDs) are extra-tropical weather systems originating in the Mediterranean and Caspian Sea regions, travelling eastward and bringing winter precipitation to northwest India:
- Origin: Mediterranean cyclonic systems, Red Sea troughs, Caspian disturbances
- Track: Travel east across Central Asia → Pakistan → northwest India → Himalayas → sometimes as far as northeast India
- Seasonal window: October–April (peak: December–March)
- Precipitation: Snowfall in Himachal Pradesh, Uttarakhand, J&K; rain in Punjab, Haryana, Delhi, UP, Rajasthan
- Agricultural role: Critical for rabi crops (wheat, mustard, chickpea) sown in October–November and harvested March–April
Why WDs weakened in 2025-26:
- Warmer than normal conditions in the Mediterranean and Middle East reduced the temperature gradient that drives WD formation
- Climate change is systematically weakening mid-latitude storm tracks — a documented pattern in multiple studies
UPSC Relevance
Prelims: El Niño (ENSO warm phase), La Niña (ENSO cool phase), NOAA El Niño 2026 probability (>80%), Southern Oscillation Index (SOI), Oceanic Niño Index (ONI), Niño 3.4 region, Western Disturbances (Mediterranean origin), Walker Circulation, India monsoon onset (June 1, Kerala), India rain-fed agriculture share (~51%), PMFBY (PM Fasal Bima Yojana), NDMA heat action plans, India food grain production FY25 (~330 MMT).
Mains GS1: Climatology — ENSO, El Niño-monsoon relationship, Western Disturbances, Indian monsoon mechanism, climate change and seasonal shifts. GS3: Agriculture — monsoon dependence, food security, drought management, crop insurance (PMFBY), MGNREGS drought employment, irrigation gap, water reservoir management.
📌 Facts Corner — Knowledgepedia
Winter 2025-26 Anomaly:
- Rainfall deficit: ~60% below normal
- Cause: Weakened Western Disturbances
- Impact: Himalayan snowpack deficit, lower river flows, groundwater deficit
El Niño 2026 Signal:
- NOAA probability: >80% (May–August 2026 development)
- Strong El Niño probability: ~33%
- Pacific signal strength: Stronger than 2023, 2018, 2015, 2014 analogues at same stage
- Measurement: Niño 3.4 SST anomaly ≥+0.5°C sustained over 5 consecutive months = El Niño
ENSO Basics:
- El Niño: Warm Pacific SSTs → suppresses Indian monsoon
- La Niña: Cool Pacific SSTs → strengthens Indian monsoon
- Walker Circulation: East-West atmospheric convection loop; disrupted by El Niño
- ONI (Oceanic Niño Index): NOAA’s primary El Niño measure; 3-month rolling Niño 3.4 average
- SOI (Southern Oscillation Index): Atmospheric pressure difference Tahiti–Darwin; negative = El Niño
India-El Niño Historical Correlation:
- ~0.6 correlation (strong, not deterministic)
- Drought years: 1972, 1982, 1987, 2002, 2009, 2014-15
- Exception: 2015-16 (super El Niño) — India’s monsoon below normal but not catastrophic
India’s Agriculture Monsoon Dependence:
- Rain-fed agriculture: ~51% of net sown area
- Agriculture % of GDP: ~15%
- Agricultural workforce: ~44% of employed population
- Food grain production FY25: ~330 million tonnes (record)
- Key Kharif crops: Rice, maize, jowar, bajra, cotton, soybean, pulses
Western Disturbances:
- Origin: Mediterranean, Caspian, Red Sea regions
- Season: October–April (peak Dec–Mar)
- Impact: Snowfall in Himalayas; rain in Punjab, Haryana, UP, Delhi
- Critical for: Rabi crops (wheat, mustard, chickpea)
Key Schemes:
- PMFBY (PM Fasal Bima Yojana): Crop insurance; government subsidised premiums; rapid satellite-based assessment
- MGNREGS: Rural employment guarantee — drought-era lifeline for agricultural workers
- NDMA Heat Action Plans: City-level heat wave response; Ahmedabad model (2010, first in Asia)
- ICAR: Indian Council of Agricultural Research; national contingency crop planning
Reservoir Status (March 2026):
- Below 10-year average storage level (due to dry winter 2025-26)
- Affects irrigation buffer ahead of Kharif season
Other Relevant Facts:
- India monsoon onset: June 1 (Kerala) — official IMD target date
- IMD forecasts El Niño impact assessment using CFSv2 (Climate Forecast System) model
- Indian Ocean Dipole (IOD): Another key climate driver; positive IOD can partially offset El Niño effects on Indian monsoon
- Galwan El Niño precedent: 2009 El Niño led to ~23% rainfall deficiency — worst in two decades; triggered food inflation and fiscal stimulus
Sources: Down to Earth, NOAA, IMD