Why even a strong El Niño does not guarantee a poor Indian monsoon

1. At a Glance

• El Niño is the warm phase of the El Niño Southern Oscillation (ENSO). When it develops, the Pacific trade winds that blow east to west weaken. Warm surface water and the rain clouds above it then move back east, away from Indonesia and towards South America. This happens every 2–7 years [6].
• El Niño usually pulls rainfall down over India, but it does not decide the outcome on its own. 1997 was a strong El Niño year, yet India's summer monsoon rainfall was normal [1].
• The main counterweight is the Indian Ocean Dipole (IOD). A positive IOD can offset El Niño. A negative IOD occurring with El Niño makes below-normal rainfall more likely [1][3].
• Why it matters for UPSC: it covers monsoon mechanics (GS-I), how reliable forecasts are, and what happens to farming and drought planning (GS-III). The 1997 vs 2026 comparison makes a good case study.

2. Why in the News

• The 2026 southwest monsoon ended about 13% below the long-term average of 87 cm [6].
• East and Northeast India had their driest monsoon since records began in 1901 [6].
• A "ferocious" El Niño is forming in 2026 and is expected to peak only in December [6].
• The Hindu (print edition, 2 November 2026) set the 2026 failure against 1997. That year one of the strongest El Niños of the 20th century still produced near-normal rainfall [6].

3. Background & Evolution

• ENSO mechanism. Near the equator, steady east-to-west winds push warm surface water towards Indonesia. That water warms the air above it, the air rises, and rain clouds form. When the winds weaken, the warm water and the clouds drift back east [6].
• Track record since 1950. Seven Indian monsoons have coincided with a moderate or strong El Niño [6]:
• 5 were "deficient" (at least 10% below the long-term average), including 2026.
• 2023 was "below average".

• 1997 was "average".

• 1997 case:

• Some had feared an extreme deficit, judging by El Niño alone [2].
• Actual June–September 1997 rainfall was 2% above normal [2].

• NOAA recorded near-normal rainfall across India, even though the monsoon ridge was weakened [4].

• IOD as the explanation:

• A positive IOD that emerged over the Indian Ocean in 1997 strengthened the monsoon [3].

• The positive IOD also helped intensify the extreme El Niño events of 1972/73, 1982/83 and 1997/98 [5].

• 2023: an El Niño year that ended "below average", not deficient [6].

4. Core Static Facts

5. Multi-Dimensional Analysis

Scientific / Technological

• The monsoon depends on several ocean basins. The Pacific (ENSO) and the Indian Ocean (IOD) interact, and a positive IOD can cancel out El Niño's effect [1][3].
• ENSO and the IOD are linked: a positive IOD helped make the 1972/73, 1982/83 and 1997/98 El Niños extreme [5].
• Forecasting based only on El Niño has a poor record. In 1997 that approach predicted an extreme deficit, and rainfall came in above normal instead [2].

Economic

• A deficient monsoon (2026: about −13%) puts pressure on rain-fed kharif output, rural incomes and food inflation [6].
• Assuming that every El Niño year will be a drought can trigger costly early measures that turn out to be unnecessary. Assessing risk by probability, as in the ENSO + IOD combination, gives better guidance for policy [1][2].

Environmental / Disaster Management

• Record dryness in East and Northeast India in 2026, normally high-rainfall regions, shows that the rainfall shortfall is unevenly spread across regions [6].
• 2026's El Niño is expected to peak in December. That raises the stakes for drought readiness after the monsoon and into the next season [6].

Administrative / Governance

• IMD's terms ("normal", "below normal", "deficient") drive drought declarations and contingency crop plans. Getting the category right therefore has real consequences [2][6].
• The gap in 1997 between the forecast and what happened shows why the IOD and other factors must be built into operational forecasts [2][3].

Historical / Comparative

• In 5 of 7 El Niño monsoons since 1950, rainfall was deficient. El Niño is therefore a strong risk factor, but not a certainty [6].

6. Recent Developments (last 12–18 months)

• June–September 2026: the southwest monsoon closed about 13% below the 87 cm long-term average [6].
• 2026 season: East and Northeast India recorded their driest monsoon since 1901 [6].
• Late 2026: a strong El Niño is still building and is expected to peak in December 2026 [6].
• 2 November 2026: The Hindu published an analysis comparing 1997 and 2026 [6].

7. Prelims Hooks

• India's long-term average southwest monsoon rainfall is 87 cm [6].
• ENSO trade-wind weakening recurs every 2–7 years [6].
• Seven Indian monsoons since 1950 coincided with a moderate or strong El Niño; five were deficient [6].
• IMD calls rainfall at least 10% below the long-term average "deficient" [6].
• 1997: a strong El Niño year, yet Indian summer monsoon rainfall was normal [1].
• June–September 1997 rainfall was 2% above normal [2].
• 2023, an El Niño year, ended "below average", not deficient [6].
• 2026 monsoon: about 13% below normal [6].
• East and Northeast India: driest monsoon on record since 1901, in 2026 [6].
• A positive IOD can offset El Niño's suppressing effect on the monsoon [3].
• A negative IOD together with El Niño raises the probability of below-normal rainfall [1].
• A positive IOD contributed to the extreme El Niños of 1972/73, 1982/83 and 1997/98 [5].
• In normal conditions, warm Pacific surface water piles up near Indonesia. During El Niño it flows back towards South America [6].

8. Was 2026 a Forecasting Failure? The Numbers Say No

• IMD warned of a weak monsoon well before it began
• In April 2026, IMD forecast rainfall at 92% of the LPA (Long Period Average, the 1971–2020 normal of 87 cm), with a possible error of ±5% [7].
• In late May it cut this to 90% of the LPA, with an error of ±4% [8].

• The actual result was about 13% below normal, or roughly 87% of the LPA [6]. That falls inside the May range (86–94%) and at the very bottom of the April range (87–97%).

• The real signal was in the probabilities

• In April, IMD put the chance of a "deficient" season (below 90% of the LPA) at 35%. In a normal year that chance is 16%, so this was more than double [7].
• By May the chance had risen to 60% [8].

• A 60% chance is a warning, not a promise. Officials who read only the single number ("90%") miss how sure the forecasters actually were.

• Why the 1997 escape route did not open in 2026

• In 1997, a positive IOD (warmer water in the western Indian Ocean than the eastern) formed during the monsoon and supported it [3].
• In 2026, IMD expected the IOD to stay neutral and to turn positive only towards the end of the season [7].

• A positive IOD that comes in September cannot make up for June–August rain that has already failed. The timing of the IOD matters, not just its sign.

• The forecast models are also different now

• IMD now combines dynamical models (computer simulations of ocean and air physics) with statistical models. One of these is the MMCFS (Monsoon Mission Climate Forecast System), built under the Ministry of Earth Sciences [7].
• The 1997 miss came from reading El Niño alone [2]. The 2026 forecast tracked El Niño and the IOD together, and it got the direction right.

9. The Case Against Treating Every El Niño as a Drought

• The strongest objection
• 1997 showed that a strong El Niño can still bring normal rain [2]. 2023 also escaped a deficit [6].
• Scientists report that the inverse link between ENSO and the monsoon (El Niño means less rain) has weakened since the early 1980s [9].

• So, the argument goes, getting ready for drought in every El Niño year wastes money and frightens farmers and markets.

• What the objection gets right

• El Niño is not a switch that turns the monsoon off. Other factors pull on it too:
  • the IOD [10];
  • the Atlantic Niño, a warm phase in the tropical Atlantic, which some studies link more strongly to Indian rain as the El Niño link weakens [11];
  • IMD also counts Eurasian snow cover as a third factor. Low snow over the northern hemisphere could offset part of El Niño's effect [15].

• One reason the link is weakening is that El Niño and a positive IOD occur together more often in a warmer climate [10].

• Why the objection still fails

• The odds still lean heavily one way. Five of the seven El Niño monsoons since 1950 were deficient [6].
• The same 2026 study that reports the weaker link also argues that greenhouse warming has made El Niño's effect on the monsoon stronger, so El Niño droughts are getting worse, not milder [9].

• The same study finds that the IOD and the Atlantic Niño are the factors least likely to break the year-to-year ENSO–monsoon link [9]. They can help in some years, but they are not a reliable safety net.

• The honest answer

• The lesson of 1997 is to check the IOD as well as El Niño, not to ignore El Niño.
• Plan according to the probability. A 60% chance of a deficit [8] calls for real preparation, though not panic.

10. Why a National Average Does Not Trigger Drought Relief

• "Deficient" means different things at different scales
• For all of India, a season below 90% of the LPA is "deficient" [7].
• For a district or subdivision, IMD calls rainfall deficient only when it is 20% to 59% below normal [12].

• So a 13% shortfall for India as a whole can sit alongside districts that are much worse off, like East and Northeast India in 2026 [6].

• Rainfall alone does not create a drought declaration

• Under the Manual for Drought Management (2016), states have to declare drought, not the Centre [13].
• Rainfall is the one compulsory indicator. States must also check four "impact" indicators: crop condition, soil moisture, water levels in rivers and reservoirs, and satellite images of crop health [12].

• A "severe" drought needs at least three impact indicators in the severe range. A "moderate" drought needs two [12].

• Money from the Centre depends on that label

• A state can send a memorandum (formal request) for NDRF (National Disaster Response Fund) assistance only if the drought is severe [12].

• So a district can be badly short of rain and still get no central money, if its other indicators do not reach the severe level.

• States can act early, but they are slow to

• The manual allows states to declare drought as early as August [13].
• In 2026, Maharashtra declared drought in 265 talukas under a first-stage "Trigger-1", based on the rainfall deficit and other set indicators [14].
• Reporting from earlier droughts shows farmers losing out while states delayed their declarations [12].

11. What IMD, the Ministry and States Should Do Next

• IMD should lead with the risk of a deficit, not one rainfall number
• Its own 2026 tables showed the chance of a deficit rising from 35% to 60% [7][8]. That figure tells a farmer or a district collector far more than "90% of LPA".

• IOD outlooks should say when a positive IOD is expected, not just whether one will form. In 2026, a late positive IOD [7] gave no protection.

• States should use the August trigger in the 2016 Drought Manual when forecast odds are high

• The manual already allows declarations in August [13].

• When IMD's chance of a deficit is high, states can begin checking crops and soil on the ground in July. That way, the impact indicators are ready when the rain fails.

• The Agriculture Ministry should review how relief is triggered in high-rainfall regions

• East and Northeast India normally get heavy rain. In 2026 they had their driest monsoon since 1901 [6].

• The severe-drought test (three impact indicators in the severe range) [12] was not designed with these regions in mind. Whether it fits them should be checked against what happened in 2026.

• Prepare beyond June–September

• The 2026 El Niño is expected to peak in December [6]. Plans for the rabi crop and for reservoirs should assume El Niño's effects are not yet over.

12. Anchors for Answers

• Data: IMD put the chance of a deficient 2026 monsoon at 60% in May, against a normal-year chance of 16% [7][8]
• Data: Five of seven moderate or strong El Niño monsoons since 1950 were deficient [6]
• Report/Committee: Manual for Drought Management, 2016 (Ministry of Agriculture & Farmers Welfare). It requires rainfall plus impact indicators, and NDRF help only for severe drought [12]
• Law/Case: Disaster Management Act, 2005, under which the NDRF is set up and drought relief is funded
• Scheme: Monsoon Mission (Ministry of Earth Sciences). Its MMCFS model feeds IMD's combined forecast [7]

13. Mains Relevance

• GS-I: Physical geography. Covers important geophysical phenomena, climatology, monsoon mechanism, and ENSO/IOD teleconnections.
• GS-III: Agriculture (irrigation, rain-fed farming, cropping patterns), disaster management (drought), and science and technology (weather forecasting).
• Possible question stems: 1. "El Niño is a necessary but not sufficient condition for monsoon failure in India." Examine this with reference to the Indian Ocean Dipole. 2. Explain why the 1997 El Niño did not cause a drought in India while the 2026 monsoon was deficient. What are the lessons for seasonal forecasting? 3. Discuss the implications of regionally uneven monsoon deficits for India's drought management framework.

14. Related Topics to Study Next

• Indian Ocean Dipole (IOD): the main modulator of El Niño's effect on India.
• Walker Circulation and Southern Oscillation: the atmospheric side of ENSO.
• La Niña: the opposite ENSO phase, usually linked to good monsoons.
• Madden–Julian Oscillation (MJO): causes active and break spells within a season.
• IMD's monsoon forecast system and rainfall categories: the terms that drive policy responses.
• Drought management in India: declarations and contingency crop plans.
• Northeast monsoon (October–December): relevant to the El Niño expected to peak in December 2026.

15. NCERT Concepts to Revise

• Indian Ocean Dipole (Geography): The IOD is the main factor that can offset El Niño, explaining why 1997 stayed normal.
• ENSO (Geography): El Niño is the warm phase of ENSO, the Pacific cycle at the centre of the note.
• Walker circulation (Geography): Explains how weakened Pacific trade winds shift warm water and rain clouds eastward during El Niño.
• Southwest monsoon (Geography): The June–September monsoon is the rainfall system whose 1997 and 2026 outcomes are compared.
• Monsoon failure (Geography): Defines 'deficient' rainfall (IMD category) and its effects on crops, prices and rural incomes, as in 2026.
• India Meteorological Department (Geography): IMD issues the forecasts and rainfall categories, such as normal and deficient, that drive drought responses.

16. Common Errors / Trap Areas

• "El Niño always means drought": wrong. In 1997, a strong El Niño year, rainfall was 2% above normal [2]. 2023 was only below average [6].
• Confusing the two IOD phases: a positive IOD helps the monsoon, and a negative IOD combined with El Niño hurts it [1][3].
• Mixing up El Niño and the IOD: El Niño is a Pacific phenomenon; the IOD is an Indian Ocean phenomenon. They interact, but they are separate [5].
• What IMD actually forecast for 1997: The Hindu says IMD forecast an 8% deficit [6]. The MAUSAM paper says IMD predicted "normal" (±10%) [2]. Check which source a question is based on.
• Assuming deficits are uniform: the 2026 national deficit (about −13%) hides a record deficit in East and Northeast India [6].