Torrential downpours, intensified by the impacts of climate change, were responsible for causing the deaths of at least 1,600 individuals and displacing millions more as deadly cyclones swept through Malaysia, Sri Lanka, and Thailand in late November, as per a recent report from the World Weather Attribution (WWA) group. Sarah Kew, a climate researcher at the Royal Netherlands Meteorological Institute and the lead author of the study, highlighted the abnormal escalation in the intensity of monsoon rains in the region, resulting in significant impacts on populations and claiming numerous lives.
A team of 21 research experts delved into the factors associated with the fatal storms. Their analysis of Cyclone Senyar across the Malacca Strait indicated a rise of 0.2 degrees Celsius in sea temperatures in the northern Indian Ocean, which contributed heat and moisture to the storms. The report noted that without the warming effects of fossil fuels, these temperatures would have been around 1 degree Celsius lower than the 30-year average.
While the study could not precisely determine the exact influence of climate change due to limitations in climate models, it emphasized the potency of heavy rainfall exacerbated by rising temperatures and the consequences of other detrimental environmental alterations. The November storms triggered catastrophic landslides and floods, submerging residences and medical facilities, and in certain regions, entire communities.
In Sri Lanka, residents of Mwathura have been engaged in rescue efforts and cleanup operations following the cyclone’s impact. Nisankka Kumarage, a local resident, recounted receiving a cyclone warning before the event, but he was taken aback when a landslide demolished part of the village, burying numerous individuals. The WWA analysis suggested that, due to climate warming effects, the likelihood of such an intense storm occurring has increased to once every 30 years, with rainfall rather than winds causing the majority of the destruction.
Early alerts were issued in Sri Lanka and Indonesia; however, many inhabitants underestimated the severity of the ensuing storms. The unfamiliarity of tropical cyclones in equatorial proximity amplified the impacts as local communities lacked prior experience in dealing with such events. The flooding, surpassing historical levels, led to extensive damage in densely populated regions due to deforestation on hillsides and urban development on floodplains, resulting in destroyed infrastructure, disrupted water supplies, and economic losses.
The preliminary assessments by WWA indicated that Sri Lanka’s economic losses amount to three to five percent of the national GDP, equating to $6 billion to $7 billion US, while Indonesian recovery costs are estimated to exceed $3 billion US. Lalith Rajapakse, an engineering professor at the University of Moratuwa in Sri Lanka, involved in the WWA study, emphasized the unprecedented nature of the torrential rainfall that induced the catastrophic flooding, surpassing historical norms. The study projected a significant increase in the intensity of extended precipitation events compared to recent decades, underscoring the urgent need for enhanced preparedness for future climate-induced extremes in the region.