Thomas Lovejoy of George Mason University, author of the “tipping point” essay, praised the new research, in which he was not involved. He said there is hope to restore the balance, at least to some extent.
“The ability to regain a margin of safety” through reforestation is very real, he clarified, and could help regain the role of trees in producing moisture within forests.
“I don’t think it will go back to what it was, but it certainly can be improved,” he said.
Forests are a fundamental part of the region’s water cycle. Moisture deposited into the air by trees generates up to 35 percent of the region’s rainfall, according to some estimates.
By managing forests with carbon sequestration, hydrology and biodiversity in mind, he said, “there are multiple benefits.” About the changes in the Amazon, he said: “It has come much earlier than anyone thought 30 years ago due to the extensive use of fire and climate change. But if you put a little water there, it will change. “
Any change may take time to come and will face political opposition. Brazilian President Jair Bolsonaro has overseen the dizzying deforestation in the Amazon. The government, under mounting pressure, recently announced plans to reverse the trend, but spikes in deforestation have continued.
In an accompanying article in the journal Nature, Scott Denning, a professor in the department of atmospheric sciences at Colorado State University, wrote that the “atmospheric profiles of the paper show that the uncertain future is happening right now.”
In an emailed response to questions, Denning hailed the new research as the first true large-scale measurement of the phenomenon, from various altitudes over thousands of kilometers and remote sectors, a step beyond traditional measurements in forest sites. The results show “that warming and deforestation in the eastern Amazon have reversed the carbon sink on a regional scale and that the change is actually manifesting itself in atmospheric CO2,” he wrote.