"Record extreme rainfall in 2024 cannot be explained by El Niño alone." Examine the role of multi-basin ocean warming in shaping global and Indian rainfall extremes.

WMO confirmed 2024 as the warmest year on record, at about 1.55 ± 0.13 °C above pre-industrial levels [2]. A recent study finds that 2024 also had a record number of heavy and extreme rainfall events worldwide [1]. El Niño contributed, but several ocean basins warming at the same time did more to shape the year's extremes.

Why El Niño alone falls short

• The 2023–24 El Niño lasted only until about May 2024 [2], yet rainfall extremes continued later into summer [1].
• Earlier strong El Niño years did not produce a similar rainfall pattern [1].
• WMO attributes the 2024 record to El Niño combined with human-induced greenhouse warming [2].

Multi-basin warming and global extremes

• The Atlantic and Indian Oceans warmed at the same time. Together with a warmer atmosphere, this spread extremes across more regions and further into the season [1].
• Record ocean heat in 2024 [3] acts as a stored energy reserve that drives evaporation and storms.
• Moisture physics: the heaviest one-day rainfall becomes about 7% more intense per 1 °C of warming, and rarer events become more frequent faster than common ones [4].

Pacific El Niño + Atlantic & Indian Ocean warming + warmer air
                          ↓
      More evaporation; air holds ~7% more moisture per °C
                          ↓
     More intense, wider-spread, longer-season downpours

Fig: Multi-basin drivers of the 2024 rainfall extremes

Implications for India

• El Niño usually weakens the Indian monsoon. Yet the 2024 monsoon ended at about 108% of the Long Period Average (LPA), with August and September well above normal [5]. This fits a warm Indian Ocean offsetting the Pacific's influence.
• More of the rain fell in fewer, more violent bursts. A "normal" seasonal total can hide cloudbursts, urban floods and landslides, such as Wayanad (July 2024).
• Extremes late in the season threaten the kharif harvest and reservoir operations. They also overwhelm drainage built for return periods worked out from past rainfall records.

Overall, El Niño decides which year spikes, while multi-basin ocean warming raises the baseline beneath it. The study projects that the 2024 pattern could become typical by 2050 [1]. India should therefore move to forward-looking design standards under the Disaster Management Act, 2005 and NDMA guidelines. IMD forecasting should also track the Indian Ocean and Atlantic, not just ENSO. This would help build the climate resilience called for under SDG 13 and the Sendai Framework.