Explanation:

Only statement 2nd is correct.

El Nino-Southern Oscillation (ENSO)

• It is a climate phenomenon resulting from the interaction between ocean and atmospheric conditions.

• The "southern oscillation" component refers to differences in sea-level air pressure over the western and eastern Pacific Oceans.

• El Nino and La Nina represent the warm and cool phases of the El Nino-Southern Oscillation (ENSO) cycle. 

• El Nino and La Nina episodes typically occur every 2 to 7 years. La Nina events may last between one and three years.

• However, it is rare for El Nino events to last longer than a year.

• Multi-year El Niño and La Nina events are those that persist for more than one year without returning to normal conditions in between.

• In 2023, La Nina concluded a three-year period, and El Nino made its presence felt. Such long-lasting ENSO phases are unusual.

Impacts of El Nino

• El Niño is characterised by an unusual warming of waters in the eastern equatorial Pacific, which has a high correlation with warmer summers in India.

The Impacts of El Nino are:

• Rains on the western coast of South America

• Drought in Northern Australia, Indonesia and India.

• Storms and Hurricanes in East Pacific

La-Nina episode represents periods of below average sea-surface temperature across the east central Equatorial Pacific.

• Global climate La Nina impacts tend to be opposite those of El Nino impacts. In the tropics, ocean temperature variations in La Nina also tend to be opposite those of El Nino.

Hence option 1st is correct.