Storms, floods, wildfires — and to a lesser degree, conflict — uprooted 40.5 million people around the world in 2020. It was the largest number in more than a decade, according to figures published Thursday by the Internal Displacement Monitoring Center, a nonprofit group based in Geneva that tracks displacement data annually.
It was all the more notable as it came during the worst global pandemic in a century.
Extreme weather events, mainly storms and floods, accounted for the vast majority of the displacement. While not all of those disasters could be linked to human-induced climate change, the Center’s report made clear that global temperature rise, fueled by the accumulation of greenhouse gases in the atmosphere, “are increasing the intensity and frequency of weather-related hazards.”
Last May, Cyclone Amphan alone displaced five million people in Bangladesh and India, as it whipped across the Bay of Bengal, downed trees and power lines, and destroyed thousands of buildings. In Bangladesh, weeks later, torrential rains upstream swelled rivers, submerging a quarter of the country and taking away the assets of its people — their homes built of mud and tin, their chickens and livestock, their sacks of rice stored for the lean times.
two ferocious hurricanes, Eta and Iota, pummeled Central America in quick succession, washing away bridges, uprooting trees and causing widespread flooding and deadly mudslides. The 2020 hurricane season was the most active Atlantic hurricane season on record, with 30 named storms, 13 of them hurricanes.
In the United States, rising temperatures and sea level rise have made flooding more frequent, particularly along the coast of the Atlantic Ocean and Gulf of Mexico, and the rate of that flooding is quickening, according to United States government researchers. At many locations, “floods are now at least five times more common than they were in the 1950s,” according to figures published recently by the Environmental Protection Agency.
Last year’s displacement numbers come as this year’s Atlantic hurricane season approaches. Scientists have projected the season will see above-normal storm activity.
Climate change has led to wetter storms because warmer air holds more moisture. And while the links between climate change and hurricanes are complex, recent research suggests that warming has made stalled Atlantic storms more common. That can be more destructive because they linger in one place for a longer period of time.