La Niña
Kartavya Desk Staff
Source: TH
Context: La Niña, a critical phase of the El Niño Southern Oscillation (ENSO), significantly influences global and regional weather patterns, including India’s monsoons and winters. Its delayed onset in 2024 has led to varied climatic effects.
About La Niña:
• What it is: A cooling phase of the Pacific Ocean, characterized by lower-than-average sea surface temperatures between Indonesia and South America.
• How it forms: Strengthened trade winds push warm water westward, allowing colder water to upwell in the central and eastern Pacific.
• Global Impacts: Increased hurricanes over the Atlantic Ocean. Droughts in Africa and western U.S. Enhanced rainfall in Southeast Asia and Australia.
• Increased hurricanes over the Atlantic Ocean.
• Droughts in Africa and western U.S.
• Enhanced rainfall in Southeast Asia and Australia.
• Impacts on India: Above-normal monsoons (e.g., 2020-2022). Colder winters in north India and cooler summer relief. Higher wind speeds, improving air quality.
• Above-normal monsoons (e.g., 2020-2022).
• Colder winters in north India and cooler summer relief.
• Higher wind speeds, improving air quality.
About El Niño:
• What it is: The warming phase of ENSO, with higher-than-average sea surface temperatures in the eastern Pacific Ocean.
• How it forms: Weakened trade winds allow warm water to accumulate in the eastern and central Pacific.
• Global Impacts: Heavy rainfall in the southern U.S. and western South America. Severe droughts in Southeast Asia, Australia, and Africa. Disruption of marine ecosystems due to warmer ocean waters.
• Heavy rainfall in the southern U.S. and western South America.
• Severe droughts in Southeast Asia, Australia, and Africa.
• Disruption of marine ecosystems due to warmer ocean waters.
• Impacts on India: Below-normal monsoons (e.g., 2023). Intense summer heat waves and prolonged droughts. Reduced agricultural output and water shortages.
• Below-normal monsoons (e.g., 2023).
• Intense summer heat waves and prolonged droughts.
• Reduced agricultural output and water shortages.
About Triple Dip La Niña:
• What it is: When La Niña conditions persist for three consecutive years (rare occurrence).
• How it forms: Sustained strengthening of trade winds and persistent cooling of the Pacific over multiple cycles.
• Global Impacts: Extended droughts in Africa and western U.S. Increased cyclone activity in Australia and Atlantic hurricanes. Prolonged disruptions in global agricultural and marine systems.
• Extended droughts in Africa and western U.S.
• Increased cyclone activity in Australia and Atlantic hurricanes.
• Prolonged disruptions in global agricultural and marine systems.
• Impacts on India: Consistent above-normal rainfall (e.g., 2020-2022). Cooler winters in north India. Enhanced agricultural yield due to robust monsoons.
• Consistent above-normal rainfall (e.g., 2020-2022).
• Cooler winters in north India.
• Enhanced agricultural yield due to robust monsoons.
Insta links:
• El-Nino and-monsoon