No doubt about it: Climate change made Hurricane Melissa way worse

Last month, Hurricane Melissa swept across the Atlantic Ocean, growing into a monstrous Category 5 storm with devastating consequences for the Caribbean islands. The storm caused severe destruction in Jamaica, Cuba, Haiti, and the Dominican Republic, tragically claiming at least 67 lives. Damage estimates from AccuWeather suggest the financial toll could reach $50 billion. Scientists had already warned that climate change played a major role in intensifying Melissa. Due to global warming, the hurricane's fuel—warm ocean waters—became up to 900 times more likely to be that hot, pushing wind speeds up by about 10 to 11 mph. Even seemingly modest increases in wind speeds can dramatically amplify damage. Researchers from World Weather Attribution found that climate change not only increased Melissa’s wind speeds but also boosted its extreme rainfall by 16 percent. The odds of such a powerful storm occurring rose by about six times due to human-driven warming. Ben Clarke, a researcher at Imperial College London, emphasized that all aspects of this event were amplified by climate change, warning that more storms like this will happen as fossil fuel emissions continue unabated. Hurricanes need three main things to strengthen: high humidity, low vertical wind shear, and warm ocean water to transfer energy. Melissa spent a long time moving slowly—about 1 to 3 mph—across exceptionally warm surface and subsurface waters, which allowed it to gather immense destructive power. Unlike some storms that cool the ocean beneath them, Melissa’s path was over warm water at depth, meaning it kept getting refueled. This helped it rapidly intensify, doubling its wind speed from 70 to 140 mph in just 18 hours—a rate far beyond the threshold for "extreme rapid intensification." This rapid strengthening near shorelines is particularly dangerous since local communities often prepare for weaker storms and get caught off guard by sudden intensification. In addition to the fierce winds, Melissa brought a massive storm surge, pushing water levels up to 16 feet in Jamaica and wrecking coastal areas. Rising sea levels, made worse by climate change, amplified the impact of this surge. Warmer waters expand, taking up more space and adding to sea-level rise. Rainfall from Melissa was catastrophic as well. A warmer atmosphere holds more moisture, which leads to heavier rain during storms. The hurricane’s extreme winds also helped squeeze more water out of the sky. In Jamaica, heavy rainfall events like this are now 30 percent more intense and twice as likely. The geography worsened flooding, as rainwater rapidly ran down mountains and into valleys. The soil was already saturated from previous rains, so it couldn’t absorb the deluge, causing widespread floods. Fortunately, advances in forecasting allowed meteorologists to predict Melissa’s rapid intensification with good accuracy, giving people valuable time to prepare. Jamaica opened hundreds of emergency shelters and Cuba evacuated over 700,000 residents from vulnerable areas. According to disaster experts, this improved forecasting likely saved many lives. However, with no recent memory of a storm this strong, preparation remains a big challenge for these communities as such powerful hurricanes become more common.