What is La Niña? Its Impact on Indian Climate & Agriculture

Table of Contents

• What is the La Niña Effect?
• What is the Global Impact of La Niña?
• Implications of La Niña for India
  • Effect on the Indian Climate
  • Effect on Indian Agriculture
• Policy Measures for Strategic Action

What is the La Niña Effect?

La Niña, ‘Little Girl’ in Spanish, is a global climatic phenomenon recognized as the cool phase of the El Niño Southern Oscillation (ENSO). Due to this climate pattern, sea surface temperatures experience periodic cooling in the central and eastern tropical Pacific Ocean. Generally, these climatic episodes occur every 2-7 years but are not regular events. A rare 3-year, triple-dip La Niña was observed between 2020–2023.

La Niña involves the movement of strong trade winds, due to which upwelling of cold water intensifies in the eastern Pacific. It is the opposite phase of El Niño and thus has contrasting effects on global weather-related events, including cold waves, heavy rainfall, and droughts. It has a significant impact during the winter and monsoon seasons in India.

What is the Global Impact of La Niña?

Due to La Niña, Pacific Ocean temperatures change and impact the tropical rainfall patterns from Indonesia to South America (west coast). La Nina effects include changes in weather patterns across the world. In North America, northern regions experience colder winters, while the southern states face warmer, drier conditions. In South America, Brazil encounters increased rainfall, while Ecuador and Peru experience drought conditions. Central America can face crop loss due to floods. 

In Asia, intense monsoons may be observed in India and South Asia. There is increased precipitation and a higher risk of flooding in Southeast Asia and Australia. When it comes to Africa, enhanced rainfall may be observed in Southern Africa. Also, there is a risk of droughts that can endanger crops and livestock.

Implications of La Niña for India

The La Nina effect in India is mainly characterized by increased, above-normal rainfall. Here’s a detailed look at the impact of La Nina India.

Effect on the Indian Climate

El Niño-Southern Oscillation (ENSO) has a big impact on the Indian climate, along with the monsoon and agriculture. More intense monsoons are observed due to La Niña, resulting in above-average rainfall in most parts of the country. Cooler temperatures can be observed post-monsoon and during winter months. Coastal regions are at risk due to increased cyclone activity in the Indian Ocean. La Niña leads to colder winters in northern India, with states like Himachal Pradesh, Haryana, and Punjab experiencing cold waves and frost.   

Effect on Indian Agriculture

The agricultural sector of India is impacted by weather patterns induced by La Niña. It is usually beneficial for monsoon-dependent crops like paddy, sugarcane, and pulses because of increased rainfall. More rainfall boosts the growth and development of several Kharif crops. In addition, it can help in recharging groundwater levels. The rainfall intensity and timing can also influence variations in crop yields.

However, there are high chances of crop damage in regions that receive flooding or excessive precipitation. Low-lying areas can get flooded, which damages standing crops, which also delays their harvesting. Waterlogging can cause pest and disease infestations to hamper yields. Due to changes in the onset and intensity of rainfall, planting schedules and variety selection need to be adjusted accordingly.

Policy Measures for Strategic Action

La Niña can easily impact water management, agriculture, health, energy, and infrastructure in India. There is a need for mitigating risks related to increased cyclone activity, extreme winters, and intense monsoon seasons.

• Adoption of flood-resistant paddy varieties like Swarna Sub1 among farmers needs to be promoted, especially in states like West Bengal, Bihar, and Assam.
• Excessive humidity can cause different crop diseases and fungal infections, so wheat sowing schedules need to be adjusted in the states of Haryana and Punjab.
•  Water management is necessary for flood-prone areas, and overflow-related disasters can be prevented through effective reservoir and dam management. Stormwater drainage is required to manage waterlogging.   
• Better infrastructure is needed for enduring heavy storms, floods, and rain. Better floodplain zoning and robust embankments must be developed in rural areas. Also, sustainable drainage solutions are an effective solution for urban areas. Cyclone shelters and storm surge barriers need upgradation for protection against severe coastal storms in cities like Visakhapatnam and Chennai.
• Waterborne disease outbreaks are common in waterlogged conditions. Mosquito control is highly important in affected areas, along with early disease surveillance and sanitation initiatives. 
• Increased monsoon rains can help increase hydropower generation while ensuring effective dam management.

As per the Ministry of Science & Technology, no impact of La Niña is expected on the monsoon in 2025. During the southwest monsoon season, neutral ENSO conditions will prevail in the current year. La Niña has both pros and cons for the Indian climate and agriculture. Thus, there is a need for strategic preparedness to handle damage to crops and infrastructure.