In a study published yesterday in the journal Science, researchers report that billions of trees died in a record drought that afflicted the Amazon in 2010. All those deaths, the scientists say, could mean that the forest could stop absorbing greenhouse gas emissions and instead add to them.
The Guardian spoke to one of the scientists:
"Put starkly, current emissions pathways risk playing Russian roulette with the world's largest forest," said tropical forest expert Simon Lewis, at the University of Leeds, and who led the research published today in the journal Science. Lewis was careful to note that significant scientific uncertainties remain and that the 2010 and 2005 drought – thought then to be of once-a-century severity – might yet be explained by natural climate variation.
"We can't just wait and see because there is no going back," he said. "We won't know we have passed the point where the Amazon turns from a sink to a source until afterwards, when it will be too late."
In other, unrelated news about the Amazon, The New York Times' Green blog points over to an arresting video about one of the Amazon's most isolated tribes. It features Jose Carlos Morales, of Brazil's Indian Affairs department, who simply wants to capture proof that these tribes exist. Illegal logging companies, he explains, are driving the tribes out of their homes and simple contact with people outside the tribe could mean death for them, because they couldn't handle certain viruses.
"They should be free to choose whether to make contact or not," Morales says. Here's the video: