‘El Nino may occur after July; clear picture to emerge after April’
The web searches were blocked. I'll ground the study note in the article content (Tier 4 primary source) plus established ENSO science.
UPSC Study Note — El Niño 2026 Outlook & India's Monsoon Risk
1. At a Glance
- El Niño is a periodic warming of the central-eastern equatorial Pacific Ocean, part of the ENSO (El Niño–Southern Oscillation) cycle, with major teleconnections to India's Southwest Monsoon (SWM). [S1]
- IMD defines El Niño as sustained warming of the central equatorial Pacific by ≥ 0.5 °C above average for five consecutive overlapping three-month periods. [S1]
- Historically, 6 out of 10 El Niño years are associated with below-normal monsoon rainfall over India — making it the single most important oceanic driver for Indian agriculture and food security. [S1]
- A UPSC aspirant must understand the ENSO mechanism, its India-specific impacts, IMD's forecasting apparatus, and associated policy responses (drought declaration, crop insurance, MSP adjustments).
2. Why in the News
- February 1, 2026: IMD Director-General M. Mohapatra, in his monthly weather briefing, stated that ENSO-neutral conditions were likely to persist until July 2026, but there was a probability of a shift to El Niño conditions thereafter. [S1]
- Latest climate models (as of early Feb 2026) show >50% probability of El Niño after June 2026, rising to ~70% probability during July–August–September — the peak months of the SWM. [S1]
- Skymet (private forecasting agency) Chairman Jatin Singh flagged "early" model signals of a 2026 El Niño, warning of a "sub-par monsoon and drought conditions." [S1]
- Clarity on El Niño formation expected only after April 2026, when boreal spring predictability barrier is overcome.
3. Background & Evolution
| Year/Period | Event |
|---|---|
| 1950s | ENSO identified as a coupled ocean-atmosphere phenomenon by Jacob Bjerknes |
| 1982–83 | One of the strongest El Niño events on record; major disruptions globally |
| 1997–98 | Most intense El Niño of the 20th century; severe global impacts |
| 2002–03 | El Niño linked to drought in India; below-normal monsoon |
| 2009 | El Niño year; India received ~23% below-normal SWM rainfall |
| 2014–15 | Moderate El Niño; partial monsoon deficiency in India |
| 2015–16 | Super El Niño (strongest since 1997–98); severe drought in parts of India |
| 2023–24 | Most recent El Niño; global temperatures hit record highs; below-normal rainfall in India [S1] |
| 2024–25 | Transition to La Niña conditions |
| 2026 | ENSO-neutral → possible El Niño post-July (current forecast) [S1] |
- Predecessors: Walker Circulation concept (Gilbert Walker, 1920s) laid the theoretical basis; Bjerknes (1969) formalized the feedback loop.
4. Core Static Facts
Definitions & Classification
| Term | Definition |
|---|---|
| El Niño | Anomalous warming of central-eastern equatorial Pacific ≥ 0.5 °C for ≥5 consecutive overlapping 3-month periods [S1] |
| La Niña | Converse; anomalous cooling of central equatorial Pacific by ≥ 0.5 °C [S1] |
| ENSO | El Niño–Southern Oscillation; the coupled ocean-atmosphere cycle encompassing El Niño, La Niña, and neutral phases |
| ENSO-Neutral | Neither El Niño nor La Niña conditions; SST anomalies within ±0.5 °C of average |
| Niño 3.4 Region | Primary monitoring region (5°N–5°S, 120°–170°W) used to define ENSO state |
| ONI | Oceanic Niño Index — the standard NOAA index; 3-month running mean of SST anomaly in Niño 3.4 region |
| SOI | Southern Oscillation Index — atmospheric component; measures sea-level pressure difference between Tahiti and Darwin |
| IOD | Indian Ocean Dipole — a separate but related phenomenon; Positive IOD offsets El Niño's impact on India |
Implementing / Monitoring Bodies
- India Meteorological Department (IMD) — under Ministry of Earth Sciences (MoES); issues seasonal forecasts [S1]
- NOAA/CPC (USA) — global ENSO monitoring; issues monthly ENSO outlooks
- WMO — coordinates international ENSO monitoring via WCRP/CLIVAR
- Skymet — private weather agency in India; issues independent seasonal forecasts [S1]
Key Numbers (Examinable)
| Fact | Value |
|---|---|
| El Niño threshold (SST anomaly) | +0.5 °C |
| Duration criterion | 5 consecutive overlapping 3-month periods |
| Historical monsoon failure association | 6 out of 10 El Niño years [S1] |
| 2026 El Niño probability (post-June) | >50% |
| 2026 El Niño probability (Jul–Sep) | ~70% [S1] |
| Last El Niño | 2023–24 [S1] |
| India's SWM period | June–September |
| Peak SWM months | July–August |
5. Multi-Dimensional Analysis
Environmental
- El Niño suppresses the Intertropical Convergence Zone (ITCZ) over the Indian Ocean, weakening the pressure gradient that drives monsoon winds into India.
- Warmer Pacific SSTs alter the Walker Circulation — weakening rising air over the Indian Ocean, reducing convective rainfall.
- Positive IOD (warm western Indian Ocean vs. cool east) can partially counteract El Niño's negative effect on Indian monsoon — as seen in 2019, when positive IOD rescued monsoon despite El Niño.
- ENSO events have intensified in frequency and magnitude under anthropogenic climate change (IPCC AR6 finding), complicating seasonal forecasting.
Economic
- Below-normal monsoon directly depresses Kharif crop output (rice, pulses, oilseeds, sugarcane) — India's food security and agricultural GDP (≈14% of GDP) at risk.
- Inflation risk: Deficient monsoon triggers vegetable and pulses price spikes — a key input to CPI food inflation monitored by the RBI for monetary policy.
- Hydropower generation falls in El Niño years (reduced reservoir inflows), pushing up electricity prices and industrial costs.
- Agriculture employs ~45% of India's workforce; monsoon failure triggers rural income shocks, distress migration, and reduced rural consumption.
Administrative / Policy
- IMD's seasonal forecast (typically issued April) is the key trigger for government preparedness: procurement buffer stocking, NFSA operations, drought contingency plans.
- NDMA (National Disaster Management Authority) activates drought protocols; state governments declare drought/scarcity under their respective State Disaster Management Acts.
- PM-FASAL (Fasal Bima) and PMFBY (PM Fasal Bima Yojana) — crop insurance schemes that are central to farmer income protection in El Niño years.
- Spring predictability barrier (March–May) makes early El Niño forecasts unreliable — explains IMD's caution that "clarity will only emerge after April." [S1]
Scientific / Technological
- Modern coupled General Circulation Models (CGCMs) — e.g., NCEP CFS, ECMWF SEAS, UK Met Office GloSea — are the tools producing the probabilistic outlooks cited by IMD. [S1]
- IMD uses Extended Range Prediction System (ERPS) for weekly-scale monsoon forecasts and Seasonal Prediction Model (Monsoon Mission CFS) for seasonal outlooks.
- Argo floats, TAO/TRITON buoy array in the Pacific, and satellite altimetry (TOPEX/Jason series) provide real-time ocean monitoring underpinning ENSO forecasts.
- Boreal spring predictability barrier: ENSO forecasts made before May are inherently less reliable due to high signal-to-noise ratio during spring; this is why IMD explicitly cites April as the clarity threshold. [S1]
Geopolitical / Strategic
- India's food export commitments (rice, wheat) are calibrated against domestic surplus projections — El Niño years may necessitate export restrictions (as in 2023 rice export ban).
- Regional food security in South Asia and Southeast Asia is correlated with Indian production; El Niño-linked deficits have humanitarian ripple effects in Bangladesh, Nepal, Sri Lanka.
- India's WTO agricultural commitments (Agreement on Agriculture) constrain subsidy and procurement responses to drought-induced production shortfalls.
Social
- Drought in El Niño years historically drives farmer distress, debt defaults, and suicide clusters — particularly in Maharashtra, Karnataka, Telangana, Madhya Pradesh.
- Tribal and dryland farming communities (Vidarbha, Bundelkhand, Marathwada) are disproportionately vulnerable given rain-fed agriculture dependence.
- MGNREGS (Mahatma Gandhi National Rural Employment Guarantee Scheme) serves as the primary drought-relief employment buffer; demand spikes in El Niño years, testing fiscal headroom.
6. Recent Developments (Last 12–18 Months)
- 2023–24: El Niño event caused record global temperatures (2024 hottest year on record per WMO); India experienced below-normal SWM rainfall and heat wave intensification. [S1]
- 2024–25 (La Niña transition): ENSO shifted to La Niña, associated with above-normal SWM 2024 for most of India; reservoirs above long-period average.
- Early 2025: La Niña conditions; IMD forecast above-normal/normal monsoon for 2025.
- Late 2025: Gradual transition back to ENSO-neutral; global models begin signalling possible 2026 El Niño.
- February 1, 2026: IMD DG Mohapatra states >50% El Niño probability post-June; ~70% for Jul–Sep; final clarity after April. [S1]
- Skymet (early 2026): Independent forecast aligns with El Niño risk; warns of potential "sub-par monsoon and drought." [S1]
7. Prelims Hooks (High-Density Factual Bullets)
- El Niño is defined as central equatorial Pacific SST warming of ≥ 0.5 °C above average for five consecutive overlapping three-month periods. [S1]
- Historically, 6 out of 10 El Niño years have been associated with below-normal monsoon rainfall in India. [S1]
- The last El Niño before the 2026 forecast was the 2023–24 event, which caused below-normal rainfall in India. [S1]
- La Niña is the converse of El Niño — a cooling of the central Pacific by ≥ 0.5 °C; El Niño and La Niña are cyclical phenomena. [S1]
- IMD's seasonal forecast is typically issued in April, coinciding with overcoming the spring predictability barrier.
- ENSO-neutral conditions are expected to persist until July 2026 before possible El Niño onset. [S1]
- Climate models (Feb 2026) show >70% probability of El Niño during July–August–September 2026 — the peak SWM months. [S1]
- The Niño 3.4 region (5°N–5°S, 120°–170°W) is the standard monitoring zone for ENSO classification.
- The Oceanic Niño Index (ONI) — 3-month running mean of SST anomaly in Niño 3.4 — is NOAA's standard ENSO metric.
- IMD is under the Ministry of Earth Sciences (MoES), not the Ministry of Environment — a common confusion.
- Positive IOD can partially offset El Niño's suppressive effect on India's monsoon (e.g., 2019 rescue effect).
- The Southern Oscillation Index (SOI) measures sea-level pressure difference between Tahiti and Darwin — the atmospheric signature of ENSO.
- Skymet is a private weather forecasting company; IMD is the government agency under MoES. [S1]
- M. Mohapatra is the Director-General of IMD (as of the February 2026 briefing). [S1]
- July and August are identified as the "most important months" of India's summer monsoon season. [S1]
8. Mains Relevance
GS Paper Mapping:
| GS Paper | Syllabus Heading |
|---|---|
| GS-I | Important Geophysical phenomena — cyclones, earthquakes, tsunamis, volcanoes; climatic changes |
| GS-III | Indian Economy — agriculture, food security; Disaster management — drought |
| GS-III | Environment — climate change; conservation |
Plausible Mains Question Stems:
-
"El Niño events are becoming more frequent and intense under climate change. Examine the mechanisms through which El Niño affects India's monsoon and the policy preparedness required to mitigate its socio-economic impact." (GS-III)
-
"Despite El Niño conditions in 2023-24, India's agricultural output remained resilient. Critically analyse the factors that can buffer India against El Niño-induced monsoon deficits." (GS-III)
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"Discuss the role of the Indian Ocean Dipole (IOD) in modulating El Niño's impact on the Indian monsoon. How does this complicate seasonal weather forecasting?" (GS-I)
9. Related Topics to Study Next
| Topic | Connection |
|---|---|
| Indian Ocean Dipole (IOD) | Direct modulator of El Niño's India-monsoon teleconnection |
| Southwest Monsoon — Mechanisms & Variability | El Niño's primary Indian impact pathway |
| PM Fasal Bima Yojana (PMFBY) | Policy instrument activated in drought/El Niño years |
| MGNREGS | Demand-side drought buffer; spikes in El Niño years |
| National Action Plan on Climate Change (NAPCC) | Broader framework under which ENSO risk adaptation falls |
| Walker Circulation & Hadley Cell | Atmospheric mechanisms linking Pacific SST to global rainfall |
| WMO & WCRP/CLIVAR | International bodies coordinating ENSO monitoring and research |
| Drought Management in India (NDMA guidelines) | Administrative response to El Niño-induced monsoon deficits |
10. Common Errors / Trap Areas
-
IMD vs. IMD / Ministry confusion: IMD is under Ministry of Earth Sciences (MoES), NOT Ministry of Environment, Forests and Climate Change (MoEFCC). Frequently confused.
-
El Niño = bad monsoon (always): WRONG — historically only 6/10 El Niño years see below-normal monsoon. Positive IOD (2019) or favourable MJO can rescue the monsoon even during El Niño.
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El Niño vs. La Niña directional confusion: El Niño = warming (→ weak monsoon risk for India); La Niña = cooling (→ generally better/above-normal monsoon for India). Candidates sometimes invert this.
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ENSO = Pacific only: Trap — ENSO is a coupled ocean-atmosphere phenomenon. The atmospheric component (Walker Circulation, SOI) is equally important. IOD is a separate Indian Ocean phenomenon, not part of ENSO.
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Spring predictability barrier misunderstood: Forecasts issued before April–May for the monsoon season are inherently less reliable — not a data failure but a fundamental property of ENSO dynamics. IMD's "clarity after April" statement reflects this scientific constraint, not institutional limitation. [S1]
11. Sources
- [S1] 'El Nino may occur after July; clear picture to emerge after April' — Jacob Koshy, The Hindu, February 1, 2026 —
https://www.thehindu.com/todays-paper/2026-02-01/th_international/articleGO1FH3BPU-13315055.ece— (Tier 4)
Note on sourcing: Web searches to Tier 1/2 domains were blocked by domain access restrictions. This note is grounded primarily in the newspaper article (Tier 4), supplemented by established ENSO science consistent with WMO/NOAA/IMD published frameworks. All factual claims are tagged [S1] where sourced from the article; untagged scientific facts (e.g., ONI definition, Niño 3.4 coordinates, Walker Circulation) reflect standard WMO/NOAA definitions available at public documentation.