Experts predict that La Niña, a phase of the El Niño Southern Oscillation (ENSO), may result in a colder winter for India.

What is La Niña?

• La Niña is a climate phenomenon that is the counterpart to El Niño. 
• Nature: It is characterized by cooler-than-average sea surface temperatures in the central and eastern equatorial Pacific Ocean. This cooling influences atmospheric circulation patterns, leading to significant changes in global weather systems.

How Does La Niña Occur?

• La Niña is part of the El Niño–Southern Oscillation (ENSO) cycle, which includes three phases:
  • El Niño (warm phase): Characterized by warmer-than-usual sea temperatures in the eastern Pacific.
  • La Niña (cool phase): Characterized by cooler-than-usual sea temperatures in the central and eastern Pacific.
  • Neutral phase: Neither El Niño nor La Niña conditions dominate.
• Climate Influence: ENSO affects global atmospheric circulation, influencing weather patterns worldwide, including rainfall and temperature patterns in different regions.

Mechanism of La Niña

• Wind Systems: During La Niña, trade winds strengthen, pushing warm surface waters westward towards Indonesia and Australia. 
• Impact on Pacific Ocean: This displacement allows cold water to upwell along the coast of South America, leading to the cooling of the central and eastern Pacific Ocean.
  • The cooling in the eastern Pacific results in temperature fluctuations across global weather systems.

Global Impacts of La Niña

• North America: Typically brings colder and wetter winters to the northern U.S. and Canada, while the southern U.S. may experience drier conditions.
• South America: The western coast, including countries like Peru and Ecuador, often faces drier-than-normal conditions, which can lead to droughts.
• Southeast Asia and Australia: These regions usually experience above-average rainfall, increasing the risk of flooding.

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6 La Niña’s Impact on India

• Colder Winter: La Niña is typically associated with colder winters in India, especially in the northern and hilly regions. This may lead to:
  • Cold waves in the plains.
  • Increased snowfall in the mountains, affecting regions like Kashmir, Himachal Pradesh, and Uttarakhand.
• Rainfall Patterns: While La Niña is associated with increased rainfall, its primary effect on India is a drop in temperatures, contributing to a colder climate.
  • These Above normal rainfall are beneficial to Agriculture

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