What Exactly Is El Niño?
El Niño is one phase of a larger phenomenon called the El Niño-Southern Oscillation (ENSO), a recurring climate pattern. In simple terms, El Niño is a significant warming of the sea surface temperatures in the central and eastern tropical Pacific Ocean
that occurs every two to seven years and can last for nine to 12 months. Normally, strong trade winds blow from east to west across the Pacific, piling up warm water in the west near Asia and Australia. During an El Niño event, these trade winds weaken or even reverse. This allows the massive pool of warm water to slosh back eastward, towards the coast of South America. This change in ocean temperature might seem distant, but it's powerful enough to disrupt atmospheric circulation patterns across the globe, leading to a cascade of weather events from droughts to floods.
The Link to India's Monsoon
The Indian monsoon is a gigantic sea breeze, driven by the temperature difference between the subcontinent and the Indian Ocean. El Niño disrupts this delicate balance. The warming of the Pacific Ocean alters a major atmospheric circulation pattern known as the Walker Circulation. Normally, this circulation leads to rising air and heavy rainfall over the western Pacific and Indian Ocean region. During an El Niño, the centre of this rainfall shifts eastward with the warm water. This results in increased sinking air, or subsidence, over the Indian subcontinent. Sinking air is dry and stable, which suppresses cloud formation and weakens the moisture-laden monsoon winds blowing towards India, often leading to reduced rainfall and, in some cases, drought.
Is El Niño Always a Villain?
Historically, El Niño has a strong correlation with below-normal monsoon rainfall in India. Since 1950, ten of the thirteen droughts India experienced occurred during El Niño years. Strong El Niño events have often coincided with severe droughts. However, the relationship isn't a perfect one-to-one equation. Not every El Niño year results in a drought. For instance, the powerful El Niño of 1997-98 saw India receive above-average rainfall. Conversely, some droughts have occurred in non-El Niño years. This shows that while El Niño creates conditions that are unfavourable for the monsoon, other climatic factors are also at play, capable of either worsening or mitigating its impact.
Meet the Monsoon's Other Influencer: The IOD
The most significant of these other factors is the Indian Ocean Dipole (IOD), sometimes called the 'Indian El Niño'. The IOD refers to the temperature difference between the western Indian Ocean (near the Arabian Sea) and the eastern Indian Ocean (near Indonesia). When the IOD is in a 'positive' phase, the western Indian Ocean becomes warmer than the east. This boosts evaporation and moisture supply, strengthening the monsoon winds and often leading to enhanced rainfall over India. A strong positive IOD can act as a counterbalance, partly offsetting the negative impact of an El Niño, as was seen in 1997. A 'negative' IOD does the opposite, weakening the monsoon, and can aggravate drought conditions if it occurs alongside an El Niño.
The Outlook for 2026
As of July 2026, meteorologists have confirmed that El Niño conditions are present and strengthening over the equatorial Pacific. Global forecasts indicate a high probability of a strong El Niño event developing through the latter half of the year. This has raised concerns, especially after a significant rainfall deficit was recorded across parts of India in June 2026. Projections suggest that the strengthening El Niño is likely to cause below-normal rainfall for the Indian subcontinent in the coming months. This has widespread implications, not just for agriculture but also for India's energy system. Reduced rainfall can lower hydropower generation, while higher temperatures driven by El Niño increase the demand for power for cooling, creating a potential energy gap. All eyes are now on whether a positive IOD might develop to provide some relief later in the monsoon season.
