Scientists said major changes in the Amazon would affect atmospheric moisture transport far beyond the forest itself.
The rainforest plays a critical role in recycling moisture through evapotranspiration, which is the process by which trees absorb water from soil and release it back into the atmosphere through their leaves. According to the study, up to 50 per cent of the Amazon’s rainfall is generated within the basin itself through this recycling process.
Large canopy trees are particularly important, contributing around 71 per cent of transpired water and recycling roughly 26 per cent of rainfall back into the atmosphere. Widespread tree loss could reduce rainfall and delay the onset of wet seasons across parts of South America, the research warned.
“Over-all, trees recycle around 36 per cent of precipitation through transpiration, substantially exceeding interception evaporation rates that amount to 22 per cent of recycled moisture. Moreover, the forest’s transpiration during the late dry season critically determines the onset of the wet season, meaning that deforestation can delay the wet season and reduce,” the study said.
This could affect agricultural regions in southern Brazil, Bolivia, Paraguay and the Río de la Plata basin in Argentina, downwind .
A previous study published in 2025 found that moisture originating from Brazilian forests supports agricultural regions across several South American countries that together account for nearly 10 per cent of global crop exports.
