El Niño and the Possibility of a “Winterless Winter”

Context

NOAA’s September 2026 assessment states that El Niño is strengthening, with more than 90% probability of a very strong event during the Northern Hemisphere autumn and winter of 2026–27. The development of a strong El Niño has raised concerns about warmer winter conditions, altered rainfall and changes in cold-wave patterns in different parts of the world.

What is El Niño?

1. El Niño is the warm phase of ENSO, characterised by unusual warming of sea-surface temperatures in the central and eastern equatorial Pacific Ocean.
2. It develops mainly due to weakening of Pacific trade winds, allowing warm water to shift eastward.
3. The resulting ocean–atmosphere interaction alters global wind circulation, jet streams, rainfall and temperature patterns.
4. El Niño generally occurs every 2–7 years and typically lasts around 9–12 months.

Impact on India’s Winter

1. Warmer Winter Conditions

1. • Recent research indicates that cold-wave frequency, duration and intensity have generally declined, with rising winter minimum temperatures.
   • Therefore, a strong El Niño combined with long-term global warming could increase the likelihood of unusually mild winter spells.

2. Changing Western Disturbances

1. • Western Disturbances (WDs) are important winter weather systems that bring rainfall and snowfall to north and northwest India.
   • ENSO can influence the circulation patterns associated with these systems.

3. Impact on Cold Waves

1. • Cold waves over north India depend on several factors, including Western Disturbances, jet-stream behaviour, cold-air advection and large-scale atmospheric circulation.
   • Hence, El Niño alone cannot determine whether India will experience a mild or severe winter.
   • Recent research indicates that La Niña years tend to favour more frequent and persistent cold-wave events compared with El Niño and neutral years.

4. Winter Rainfall and Snowfall

1. • Winter precipitation in northwest India is closely linked to Western Disturbances.
   • Changes in their frequency, intensity or trajectory can affect Himalayan snowfall, winter rainfall and water availability.
   • This has implications for rabi agriculture, hydropower, groundwater recharge and spring–summer water supply.

Why “Winterless Winter” Matters for India

1. Agriculture: Wheat and other rabi crops require suitable winter temperatures; abnormal warming can affect crop growth and yields.
2. Water Resources: Reduced Himalayan snowfall can influence summer water availability in snow-fed river systems.
3. Public Health: A warmer winter may reduce cold-related illnesses but can create conditions favourable for some vector-borne diseases and heat stress.
4. Ecosystems: Changes in temperature and snowfall can disturb seasonal biological cycles and Himalayan ecosystems.
5. Energy Demand: A warmer winter may reduce heating demand but alter electricity and energy-consumption patterns.
6. Tourism: Reduced snowfall can affect winter tourism and snow-dependent livelihoods in the Himalayan region.

Factors Other Than El Niño

A “winterless winter” cannot be attributed to El Niño alone.

1. Global warming: Rising baseline temperatures are increasing the likelihood of warmer winters.
2. Western Disturbances: Their frequency and trajectory strongly influence north Indian winter weather.
3. Jet-stream variability: Changes in the subtropical westerly jet can alter cold-air movement.
4. Arctic warming: Changes in Arctic circulation can influence cold-air outbreaks over Eurasia.
5. Indian Ocean conditions: IOD and Indian Ocean sea-surface temperatures can modify ENSO-related impacts.
6. Local weather variability: Fog, cloud cover, wind direction and soil moisture can produce large short-term temperature variations.

Challenges

1. Uncertain regional response: El Niño does not produce the same impact everywhere.
2. Complex teleconnections: Pacific warming interacts with the Indian Ocean, jet streams and atmospheric circulation.
3. Weak predictability of local extremes: Seasonal forecasts cannot precisely predict individual cold waves or warm spells months in advance.
4. Climate-change interaction: Rising background temperatures can amplify or modify natural climate variability.
5. Agricultural vulnerability: Changes in winter temperature and rainfall can affect rabi crops and food security.

Way Forward

1. Strengthen seasonal forecasting: Improve ENSO and winter forecasts using ocean, satellite and atmospheric observations.
2. Develop impact-based warnings: Provide region-specific advisories for farmers, health agencies and disaster-management authorities.
3. Climate-resilient agriculture: Promote heat-tolerant and climate-resilient crop varieties and adjust sowing practices where required.
4. Monitor Western Disturbances: Improve prediction of WD frequency, intensity and trajectory for better winter-weather preparedness.
5. Strengthen Himalayan monitoring: Track snowfall, glaciers, temperature and water availability.
6. Integrate climate risks into planning: Incorporate changing winter patterns into agriculture, water, health and disaster-management policies.
7. Avoid ENSO-only explanations: Assess El Niño together with global warming, IOD, Arctic variability and regional atmospheric circulation.

FAQs

1. What is El Niño?
   El Niño is the warm phase of ENSO, marked by abnormal warming of the central and eastern equatorial Pacific Ocean.
2. Why can El Niño influence India’s winter?
   El Niño modifies large-scale atmospheric circulation and jet-stream patterns, which can influence Western Disturbances, winter rainfall and temperature over India.
3. Does El Niño always cause a warm winter in India?
   No. India’s winter is influenced by multiple factors, including Western Disturbances, jet streams, Arctic circulation, IOD and local weather conditions.
4. What is meant by “winterless winter”?
   It refers to a warmer, shorter or less consistently cold winter, rather than the complete disappearance of winter.
5. How can a warmer winter affect agriculture?
   Higher temperatures can alter the growth cycle and productivity of rabi crops, particularly temperature-sensitive crops such as wheat.
6. What is the role of Western Disturbances?
   They are eastward-moving weather systems that bring winter rainfall to northwest India and snowfall to the Western Himalayas.