Monsoon Shift: El Niño Triggers Coastal Swell Surges

Changes in monsoon sea conditions due to El Niño have resulted in frequent swell surges along India's western coast. This phenomenon has led to repeated alerts during the southwest monsoon, unlike in previous years when warnings were typically issued before this period. The Indian National Centre for Ocean Information Services (INCOIS) has issued alerts, including red alerts for Kerala and southern Tamil Nadu, and orange alerts for coastal Karnataka.

Swell surges are caused by powerful waves generated by distant storms, such as hurricanes, or prolonged periods of strong winds. These waves carry significant energy across vast distances before reaching the coast. Typically, these swells originate from the southern Indian Ocean and travel northwards.

This monsoon season, the Kerala coast has seen 14 swell surge alerts, with two classified as red alerts. This occurred even as mainland Kerala reported a 28% deficit in monsoon rainfall. The calm sea conditions, attributed to El Niño, have made these distant swell waves more noticeable, necessitating specific alerts unlike in the past when monsoon waves also contributed to rough seas.