Roadmap for Answer Writing

1. Introduction (30-40 words)

• Briefly introduce ENSO as a recurring climate phenomenon.
• Mention that it involves changes in sea surface temperatures in the Pacific Ocean, influencing weather patterns globally.

Example:
“The El Niño-Southern Oscillation (ENSO) is a periodic climate pattern that alternates between two phases—El Niño and La Niña—affecting global weather and climate systems, including significant impacts on India’s monsoon and agriculture.”

1. Explanation of ENSO Phenomenon (80-100 words):
   • Define the El Niño and La Niña phases.
   • Explain the mechanism behind the changes in sea surface temperatures in the tropical Pacific.
   • Describe how ENSO affects global atmospheric circulation and weather patterns.

   Key Facts:

   • ENSO refers to the fluctuation of ocean temperatures in the central and eastern Pacific Ocean.
   • El Niño: Characterized by weakened trade winds, causing warmer-than-normal waters.
   • La Niña: Characterized by stronger trade winds, causing cooler-than-normal waters.
   • The changes in ocean temperature and atmospheric pressure impact global weather patterns.

2. Global Climate Impact (80-100 words)

• Discuss how El Niño and La Niña affect different regions worldwide.
• Provide examples for major areas like South America, Australia, North America, and Europe.

Key Facts:

1. • El Niño causes heavy rains and flooding in South America (Ecuador, Peru), droughts in Australia and Southeast Asia, and milder winters in North America and Europe.
   • La Niña leads to drought in South America, heavy rainfall in Southeast Asia, and colder winters in Southern Europe.
2. Impact on Indian Climate (100-120 words):
   • Discuss how El Niño and La Niña specifically affect India, focusing on the monsoon, agriculture, and winter temperatures.
   • Mention how ENSO influences rainfall, drought, and temperature patterns across different regions of India.

   Key Facts:

   • El Niño: Weakens the southwest monsoon, reducing rainfall, leading to drought-like conditions, particularly impacting agriculture. This can result in economic losses in sectors dependent on monsoon rainfall.
   • La Niña: Strengthens the monsoon, leading to excess rainfall, which is generally beneficial for Indian agriculture. However, it can also bring cooler-than-usual winters, particularly in North India and the southern state of Tamil Nadu.
3. Conclusion (30-40 words):
   • Summarize the key points: ENSO’s periodic occurrence and global impact, with particular reference to its influence on India’s climate.
   • Suggest the need for preparedness in India to deal with ENSO’s effects, especially on agriculture and economy.

   Example:
   “The ENSO phenomenon significantly influences global weather patterns, with considerable effects on India’s monsoon and agriculture. Understanding and anticipating ENSO events can help mitigate their adverse effects, particularly on food security and economic stability.”

Relevant Facts and Sources:

• ENSO Mechanism: ENSO is a periodic fluctuation in sea surface temperatures in the central and eastern tropical Pacific Ocean, affecting global weather patterns (National Oceanic and Atmospheric Administration, NOAA).
• El Niño Effects: El Niño weakens trade winds, leading to warmer-than-normal ocean water and disrupted weather systems (NOAA).
• La Niña Effects: La Niña strengthens trade winds, resulting in cooler-than-normal sea temperatures and altered global climate patterns (National Institute of Oceanography).
• Impact on India:
  • El Niño: Weakens the southwest monsoon, causing droughts and negatively impacting agriculture (Indian Meteorological Department).
  • La Niña: Enhances monsoon rainfall, which typically benefits Indian agriculture but can cause floods in some regions (IMD).