WASHINGTON, D.C. — A new high-resolution climate study warns that the complete deforestation of the Amazon rainforest would trigger a shift to significantly harsher weather extremes, characterized by longer dry periods, explosive rainstorms, and dangerous heat.
The research, which utilized a storm-resolving global model, found that removing the forest would effectively transform the region’s weather, creating a meaner climate even if the annual total rainfall volume remained largely unchanged.
The study concluded that deforestation would cause the hourly pattern of precipitation to splinter. Hours with “no rain” would nearly triple, as the absence of the tree canopy makes storm formation more difficult. Conversely, when storms do fire, they become significantly more violent; extreme downpours (defined as more than two inches in a single hour) are projected to surge by about 54 percent, increasing the risks of flash flooding.
Without the crucial cooling effect of evapotranspiration from the trees, surface temperatures across the basin would also climb dramatically. Near-surface air temperatures would warm by an average of approximately 6.8 The heat would be relentless, as daily minimum temperatures would increase by roughly 4.9 making post-deforestation nights as hot as pre-deforestation days across much of the Amazon.
Further compounding the risks, the loss of the tall, rough tree canopy would dramatically reduce surface friction, causing average wind speeds at 33 feet above ground to more than triple. This, combined with stronger downdrafts from the fiercer storms, poses a severe threat to young, shallow-rooted trees attempting to regrow. The ultimate consequence for the more than 30 million people living in the Amazon would be compounded stressors across health, infrastructure, and agriculture.