Climate change supercharged the deadly monsoon floods that killed more than 1,750 people across Asia by making storms more intense, scientists have concluded. Analysis by World Weather Attribution found that five-day periods of heavy rain in the region hit by Cyclone Senyar are now 28 to 160 per cent more intense due to global heating.
In Sri Lanka, where Cyclone Ditwah caused severe flooding, the intensity of heavy rain has increased by 9 to 50 per cent. Some areas saw floodwaters reach up to 15 feet, far exceeding the normal one to two feet. “Monsoon rains are normal in this part of the world. What is not normal is the growing intensity of these storms,” said Dr Sarah Kew, lead author of the study.
The scientists said that forest destruction in Sumatra worsened the flooding, as cleared land allowed rainwater to run off hillsides more quickly. Tens of millions were affected when the cyclones struck Indonesia, Sri Lanka and Malaysia in late November. Hundreds remain missing, and the poorest communities have been hit hardest, losing homes and livelihoods.
Professor Lalith Rajapakse of the University of Moratuwa said the cyclones have become “an alarming new reality” for the region, bringing unprecedented rainfall and widespread loss of life. The study noted that natural climate variability such as La Niña played a role, but concluded that human-caused climate change had clearly amplified the downpours.
Maja Vahlberg of the Red Cross Red Climate Centre highlighted that the most vulnerable people experienced the worst impacts. “Over decades, growth has increasingly taken place in low-lying floodplains and river corridors, which are economic hubs but also natural flood paths,” she said. The scientists urged a reduction in fossil fuel use to prevent future extremes.
