Extreme Rainfall in a Warming World Across Multiple Oceans

Context: Why in News?

A study cited in the newspaper reported a record number of heavy and extreme rainfall events in 2024. Unlike a typical El Niño year, the simultaneous warming of the Pacific, Atlantic and Indian Oceans, along with rising atmospheric temperatures, intensified extreme rainfall events.

Key Highlights

• Rising air temperatures enable the atmosphere to hold more water vapour, increasing the potential intensity of rainfall.
• Sea surface warming across multiple ocean basins can interact through atmospheric teleconnections, influencing weather patterns across distant regions.
• El Niño alone may not fully explain regional rainfall extremes when the Atlantic and Indian Oceans are also experiencing unusually high temperatures.
• Climate models suggest that rainfall patterns currently considered rare could become more common by around 2050 if global warming continues.
• The risk associated with extreme rainfall depends on the intensity of the hazard, the exposure of people and infrastructure, and their vulnerability. Therefore, total seasonal rainfall alone is insufficient to assess the overall risk.

Way Forward

Rainfall intensity duration frequency curves, urban drainage standards and dam operation guidelines should be revised using climate data that accounts for changing weather patterns. Improved radar coverage and flash flood warning systems are also essential. In addition, floodplain regulation and climate resilient land use planning should be strengthened to reduce the impacts of extreme rainfall events.