Reduced rainfall across the Amazon basin is causing large areas of forests to die, which could be amplifying drought conditions across the region.
Researchers from the Potsdam Institute for Climate Impact Research believe that this process, known as self-amplifying forest loss, could cause a vicious circle of drought and further forest loss across the Amazon region, according to a study published in Nature Communications.
"We already know that on the one hand, reduced rainfall increases the risk of forest dieback, and on the other hand, forest loss can intensify regional droughts," lead-author of the study, Delphine Clara Zemp, said in a statement, calling the Amazon "one of the tipping elements in the Earth system."
The survival of tropical forests depends on the very water that they hold, according to PIK researchers, who studied water fluxes across the region to determine the level of interaction between vegetation and the atmosphere.
In the Amazon, one of the most important carbon sinks on the planet, trees evaporate the moisture that will eventually rain back onto them.
"As powerful as the cycle is, it is also surprisingly susceptible to environmental changes," co-author Henrique M.J. Barbosa from the Universidade de Sao Paulo said in a statement. "And humankind is imposing massive perturbations on Amazonia by both cutting down the trees and heating up the air with greenhouse gases."
This, Barbosa explained, has the effect of reducing large-scale moisture transportation and rainfall.