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

URL: https://upsc.help/current-affairs/2026-11-02/el-nino-monsoon-not-destiny-explained/
Date: 2 November 2026 (2026-11-02)
Source: The Hindu, Page II
UPSC papers: GS1, GS3
Publisher: upsc.help (Pratidin), free and open-source UPSC Civil Services current affairs. Not affiliated with UPSC. Every fact was checked against the source reports by a separate review before publishing.

**In one line:** El Niño usually weakens India's monsoon, but the Indian Ocean Dipole, the location of Pacific warming and intraseasonal waves can soften or deepen its effect, as the contrast between 1997 and 2026 shows.

India's 2026 southwest monsoon ended with 759.4 mm of rain against a normal of 868.6 mm, 12.6% below normal and the weakest season since 2015, during a strong El Niño. A Hindu explainer on 2 November 2026 asks why El Niño, the periodic warming of the central and eastern equatorial Pacific, does not always produce a poor monsoon. It counts seven Indian monsoons since 1950 that coincided with a moderate or strong El Niño. Five of them, including 2026, were deficient (at least 10% below the long-period average), 2023 was below normal, and 1997 was normal.

The main offsetting factor is the Indian Ocean Dipole (IOD), the difference in sea surface temperature between the western Indian Ocean near Africa and the eastern Indian Ocean near Indonesia. A positive IOD, with a warmer west, helps draw moisture to India. In 1997 a strong positive IOD partly neutralised one of the strongest El Niño events on record, and the warmest Pacific water lay farther east, near South America. In 2015 the IOD barely developed, which the explainer links to a shift in the westerly wind belt around Antarctica. The Madden-Julian Oscillation, a band of cloud and rain that circles the tropics every 30 to 60 days, also matters: in August 2023 it stayed away from India, which had its driest August since 1901.

The explainer notes that the IMD updates its April monsoon forecast at the end of May and has combined several global climate models since 2021. Its forecasts come with an error margin, and in 2026 the IOD stayed neutral, as IMD's model had expected, while some other models had predicted a positive IOD. The stakes are high: the monsoon brings about three-quarters of India's annual rainfall and about 40% of farmland is unirrigated. The lesson, the explainer argues, is that El Niño raises the risk of a poor monsoon but does not decide it on its own.

## Prelims facts

- The 2026 monsoon ended 12.6% below normal (759.4 mm against 868.6 mm), the weakest since 2015.
- Of seven moderate or strong El Niño monsoons since 1950, five were deficient; 2023 was below normal and 1997 normal.
- A positive Indian Ocean Dipole (warmer western Indian Ocean) can offset El Niño, as in 1997.
- The Madden-Julian Oscillation circles the tropics every 30 to 60 days; August 2023 was India's driest August since 1901.
- IMD has used a multi-model ensemble for monsoon forecasts since 2021.

## Quick recall

- **2026 monsoon rainfall against normal?** 759.4 mm against 868.6 mm, 12.6% below normal, the weakest since 2015.
- **What is a deficient monsoon?** Seasonal rainfall at least 10% below the long-period average.
- **Moderate or strong El Niño monsoons since 1950 counted in the explainer, and how many were deficient?** Seven; five were deficient.
- **Which strong El Niño year had a normal Indian monsoon, and why?** 1997, helped by a strong positive Indian Ocean Dipole.
- **What is a positive Indian Ocean Dipole?** Western Indian Ocean warmer than the eastern Indian Ocean near Indonesia.
- **Period of the Madden-Julian Oscillation?** About 30 to 60 days, moving eastward around the tropics.
- **Driest August in India since 1901?** August 2023.
- **Since when has IMD used a multi-model approach for monsoon forecasts?** 2021.

## Prelims practice question

With reference to the Indian monsoon, consider the following statements:
1. A positive Indian Ocean Dipole is associated with a warmer western Indian Ocean relative to the eastern Indian Ocean.
2. Every moderate or strong El Niño year since 1950 has produced a deficient Indian monsoon.
3. The Madden-Julian Oscillation is an eastward-moving disturbance that circles the tropics in about 30 to 60 days.
Which of the statements given above are correct?

(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

Answer: (c) 1 and 3 only. Statement 1 is correct. Statement 2 is wrong: of seven such years, 1997 was normal and 2023 below normal but not deficient. Statement 3 is correct.

## UPSC previous-year questions this connects to

- UPSC Mains 2014, GS1: Most of the unusual climatic happenings are explained as an outcome of the El-Nino effect. Do you agree? (https://upsc.help/pyq/q030-most-unusual-climatic-happenings-explained-outcome-el-nino/)
  How to use this story in the answer: Argue that El Niño is a major but not sole driver, using the IOD, MJO and the record of El Niño monsoons since 1950.
- UPSC Prelims 2017, Prelims: With reference to 'Indian Ocean Dipole (IOD)' sometimes mentioned in the news while forecasting Indian monsoon, which of the following statements is/are correct? 1. IOD phenomenon is characterised by a difference in sea surface temperature between tropical Western Indian Ocean and tropical Eastern Pacific Ocean. 2. An IOD phenomenon can influence an El Nino's impact on the monsoon. (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2 (https://upsc.help/pyq/q032-reference-indian-ocean-dipole-iod-sometimes-mentioned/)
- UPSC Mains 2014, GS3: Drought has been recognised as a disaster in view of its spatial expanse, temporal duration, slow onset and lasting effect on various vulnerable sections. With a focus on the September 2010 guidelines from the National Disaster Management Authority, discuss the mechanism for preparedness to deal with the El Nino and La Nina fallouts in India. (https://upsc.help/pyq/q029-drought-has-recognised-disaster-view-spatial-expanse/)

## Mains practice question

"El Niño raises the risk of a poor Indian monsoon but does not decide it." Examine this statement with reference to the Indian Ocean Dipole and other factors. (250 words)

### Model answer

El Niño, the warming of the central and eastern equatorial Pacific, usually suppresses India's monsoon, yet its effect varies from year to year.

## Why El Niño raises the risk
- It shifts the Walker circulation, bringing dry, sinking air over India.
- Of seven moderate or strong El Niño monsoons since 1950, five were deficient, including 2026 (12.6% below normal).

## Why it does not decide
- **Indian Ocean Dipole:** a positive IOD draws moisture to India; in 1997 it partly cancelled a very strong El Niño and the monsoon was normal.
- **Location of warming:** in 1997 the warmest water lay far east near South America; central Pacific warming hurts India more.
- **Madden-Julian Oscillation:** its 30 to 60 day cycle can cause long breaks; August 2023 was the driest since 1901.
- **Remote drivers:** a shift in Antarctic westerlies is linked to the weak IOD of 2015.

## Implications
- Forecasts need multi-model ensembles, as IMD has used since 2021.
- Contingency crop plans, water storage and food stocks should respond to risk, not certainty.
- The monsoon brings about three-quarters of annual rainfall and about 40% of farmland is unirrigated, so even a probable shortfall demands early action.
- Better observation of the Indian Ocean would improve IOD forecasts, a known weak spot.

El Niño is a strong signal, but India's monsoon is shaped by an interplay of Pacific, Indian Ocean and atmospheric factors.

## The basics

## Why this matters
The 2026 monsoon ended 12.6% below normal during a strong El Niño. Yet in 1997, during one of the strongest El Niño events on record, India's monsoon was close to normal. A Hindu explainer on 2 November 2026 asks why. The answer, that several ocean and atmospheric systems interact, is classic GS1 geography and a frequent Prelims theme.

## What El Niño is
El Niño is the periodic warming of the central and eastern equatorial Pacific Ocean, linked to a weakening of the trade winds and a shift in the Walker circulation, the east-west loop of air over the Pacific. It is the warm phase of the El Niño-Southern Oscillation (ENSO). Over India it tends to bring sinking, dry air and a weaker monsoon.

## Not one factor but several
The explainer counts seven monsoons since 1950 that coincided with a moderate or strong El Niño. Five of them, including 2026, were deficient, at least 10% below the long-period average. 2023 was below normal, and 1997 was normal.

## The Indian Ocean Dipole
The main offsetting factor is the Indian Ocean Dipole (IOD): the difference in sea surface temperature between the western Indian Ocean near Africa and the eastern Indian Ocean near Indonesia. In a positive IOD the west is warmer, which helps draw moisture towards India. In 1997 a strong positive IOD partly cancelled El Niño. In 2015 the IOD barely developed, and the explainer links this to a shift in the westerly wind belt around Antarctica.

## Other players
Where in the Pacific the warmest water lies also matters: warming in the central Pacific is more likely to send dry, sinking air over India. The Madden-Julian Oscillation, a band of clouds and rain that circles the tropics every 30 to 60 days, can bring or withhold rain for weeks. In August 2023 it stayed away from India, and the month was the driest August since 1901. The IMD now combines several global models in its IMD monsoon forecasting, and its forecasts carry an error margin. Background: El Niño-Southern Oscillation.

## Sources

- https://kpiasacademy.com/el-nino-and-indian-monsoon/
- https://www.legacyias.com/the-hindu-upsc-news-analysis-for-02-november-2026/
- https://dailypioneer.com/india/why-this-el-nino-has-hit-indias-monsoon-so-hard