Impact of climate change on El Niño-Southern Oscillation:

GS Paper 1

Topics Covered: Important Geophysical phenomena such as earthquakes, Tsunami, Volcanic activity, cyclone etc.

Context:

There is a growing body of research suggesting that climate change can cause extreme and more frequent El Niño and La Niña events.

• A study was conducted recently on this using one of South Korea’s fastest supercomputers,

Findings of the latest study:

1. Increasing atmospheric carbon dioxide can cause a “weakening of future simulated ENSO sea surface temperature variability.”
2. Future El Niño events will lose heat to the atmosphere more quickly due to the evaporation of water vapour.
3. In the future there will be a reduced temperature difference between the eastern and western tropical Pacific, inhibiting the development of temperature extremes during the ENSO cycle.
4. Also, there can be a weakening of tropical instability waves in the projected future, which can cause a disruption of the La Niña event.

What are the Niño and La Niña?

They are two natural climate phenomena occurring across the tropical Pacific Ocean and influence the weather conditions all over the world.

• While the El Niño period is characterised by warming or increased sea surface temperatures in the central and eastern tropical Pacific Ocean, a La Niña event causes the water in the eastern Pacific Ocean to be colder than usual.
• Together, they are called ENSO or El Niño-Southern Oscillation.

What causes El Nino?

1. El Nino sets in when there is an anomaly in the pattern.
2. The westward-blowing trade winds weaken along the Equator and due to changes in air pressure, the surface water moves eastwards to the coast of northern South America.
3. The central and eastern Pacific regions warm up for over six months and result in an El Nino condition.

Insta Curious:

Do you know about Param Shivay, a Supercomputer built under the National Super Computing Mission? Reference: https://www.cdac.in/index.aspx?id=pk_itn_spot1230.

InstaLinks:

Prelims Link:

1. What is El Nino?
2. What is La Nina?
3. What is ENSO?
4. When do these events occur?
5. Impact of ENSO on Asia, Africa and Australia.

Mains Link:

Discuss the impact of La Nina weather phenomenon on India.

Sources: Indian Express.