3. Which atmospheric phenomenon, characterised by eastward-propagating disturbances across the tropical Indian Ocean and the western Pacific Ocean, influences the Indian monsoon variability?
Select the correct option from the following:
Answer: Option D - Madden-Julian Oscillation (MJO)
Explanation:
- Madden-Julian Oscillation (MJO) - it is a tropical phenomenon with eastward-moving waves of convection (areas of rising air) that propagate across the Indian Ocean and the western Pacific Ocean.
- These convection waves can enhance or suppress monsoon rainfall depending on the phase of the oscillation. So, MJO directly influences the variability of the Indian monsoon.
- Pacific Decadal Oscillation (PDO): This phenomenon primarily affects climate patterns in the Pacific Ocean over longer timescales (decades) and has a lesser influence on the Indian monsoon.
- Southern Annular Mode (SAM): SAM primarily influences high-latitude atmospheric circulation patterns in the Southern Hemisphere and has minimal impact on the Indian monsoon.
- Southern Oscillation (SO): While SO, along with its oceanic counterpart El Niño, affects global climate patterns, its influence on the Indian monsoon is indirect compared to MJO.
Answer: Option D - Madden-Julian Oscillation (MJO)
Explanation:
- Madden-Julian Oscillation (MJO) - it is a tropical phenomenon with eastward-moving waves of convection (areas of rising air) that propagate across the Indian Ocean and the western Pacific Ocean.
- These convection waves can enhance or suppress monsoon rainfall depending on the phase of the oscillation. So, MJO directly influences the variability of the Indian monsoon.
- Pacific Decadal Oscillation (PDO): This phenomenon primarily affects climate patterns in the Pacific Ocean over longer timescales (decades) and has a lesser influence on the Indian monsoon.
- Southern Annular Mode (SAM): SAM primarily influences high-latitude atmospheric circulation patterns in the Southern Hemisphere and has minimal impact on the Indian monsoon.
- Southern Oscillation (SO): While SO, along with its oceanic counterpart El Niño, affects global climate patterns, its influence on the Indian monsoon is indirect compared to MJO.