With reference to ‘Indian Ocean Dipole (IOD) sometimes mentioned in th

With reference to ‘Indian Ocean Dipole (IOD) sometimes mentioned in the news while forecasting Indian monsoon, which of the following statements is/are correct?
1. IOD phenomenon is characterised by a difference in sea surface temperature between tropical Western Indian Ocean and tropical Eastern Pacific Ocean.
2. An IOD phenomenon can influence an El Nino’s impact on the monsoon.
Select the correct answer using the code given below:

1 only
2 only
Both 1 and 2
Neither 1 nor 2
This question was previously asked in
UPSC IAS – 2017
Statement 2 is correct, while statement 1 is incorrect.
– Statement 1 is incorrect. The Indian Ocean Dipole (IOD) is an irregular oscillation of sea surface temperatures in which the western Indian Ocean becomes alternately warmer and then colder than the eastern part of the ocean. It is characterised by a difference in sea surface temperature between a western pole in the Arabian Sea (western tropical Indian Ocean) and an eastern pole in the eastern Indian Ocean south of Indonesia. The statement incorrectly mentions the Eastern Pacific Ocean, which is associated with El Niño-Southern Oscillation (ENSO).
– Statement 2 is correct. The IOD is a significant climate driver for countries around the Indian Ocean, including influencing the Indian monsoon. IOD and ENSO are two separate climate phenomena, but they can interact and influence each other’s impact on regional weather patterns, including the Indian monsoon. A positive IOD, for instance, is often associated with a good monsoon in India and can sometimes counteract the negative impact of an El Niño event.
A ‘positive IOD’ occurs when the western Indian Ocean is warmer and the eastern Indian Ocean is colder than average. A ‘negative IOD’ is the opposite. The IOD is often called the “Indian Niño” because of its similarity to the Pacific El Niño phenomenon.