Context
The India Meteorological Department (IMD) has forecast “below-normal” southwest monsoon rainfall at 92% of the Long Period Average (LPA) for 2026, indicating a possible weakening of the monsoon due to the emergence of El Niño conditions.
Long Period Average (LPA)
LPA=87 cmLPA = 87\ cmLPA=87 cm
The Long Period Average (LPA) is the average monsoon rainfall calculated over a long-term period (1971–2020 for India).
- IMD uses it as the benchmark for assessing monsoon performance.
- Rainfall below 90% of LPA is classified as “deficient”.
What is El Niño?
ENSO=El Nin~o+La Nin~aENSO = El\ Niño + La\ NiñaENSO=El Nin~o+La Nin~a
El Niño is a climatic phenomenon marked by abnormal warming of sea surface temperatures in the eastern and central Pacific Ocean.
It forms one phase of the El Niño Southern Oscillation (ENSO), a global ocean-atmosphere interaction influencing weather patterns worldwide.
Mechanism
- Weakening of trade winds allows warm Pacific waters to shift eastward.
- This disrupts the normal Walker Circulation.
- As a result, convection and rainfall over the Indian region weaken.
Climatic Drivers of Indian Monsoon
ENSO Effect
El Niño generally weakens the Indian monsoon, whereas La Niña strengthens it.
Indian Ocean Dipole (IOD)
A positive Indian Ocean Dipole enhances monsoon rainfall and may partially offset El Niño effects.
Snow Cover
Lower Eurasian snow cover supports stronger monsoon circulation.
Walker Circulation
Changes in east-west atmospheric circulation influence moisture transport towards India.
Jet Streams
The position and intensity of subtropical jet streams affect monsoon onset and distribution.
Global Warming
Climate change increases monsoon variability and extreme rainfall events.
Impacts of Below-Normal Monsoon
Agricultural Stress
Nearly 60% of Indian farmers depend on monsoon rainfall, making Kharif agriculture highly vulnerable.
Rural Income Shock
Poor rainfall reduces agricultural output and rural consumption demand.
Water Scarcity
Deficient rainfall lowers groundwater recharge and drinking water availability.
Energy Impact
Reduced reservoir levels negatively affect hydropower generation.
Food Inflation
Lower crop production can increase food prices and inflationary pressure.
Conclusion
The forecast of a below-normal monsoon highlights the increasing vulnerability of India’s climate-sensitive economy to global climatic phenomena such as El Niño. Strengthening climate resilience, improving water management, and promoting climate-smart agriculture are essential for mitigating the socio-economic impacts of monsoon variability.