Every two weeks for the last ten years, climate scientist Luciana Gatti of the National Institute for Space Research in São José dos Campos, Brazil, has collected air samples at five sites in the Amazon rainforest. Her team’s latest findings, covered in depth in a Nature feature story, warn that the Amazon, once reliably capturing and storing carbon, is becoming a source of carbon emissions, instead, as deforestation and degradation erode the forests’s ability to store carbon. In 2019 and 2020, under former Brazilian president Jair Boslonaro’s policies of exploiting the forest, the region’s carbon emissions doubled as trees were cut down and land burned for agriculture.

“They are killing the forest to transform everything into soy beans.” Gatti said. “I’m observing the forest dying.” She’s not alone. Another study published in Nature yesterday found that tropical forests are at risk for “total leaf death” if emissions are unchecked, leading to rising temperatures reaching the point at which leaves can no longer photosynthesize. The good news, according to professor Simon Lewis, is that “under low-emissions scenarios, almost all tropical forest tree leaves can avoid death from overheating and the trees will survive” though they will still face overheating during heat waves. (Amazon: Nature, The Guardian, Reuters; Forests overheating: The Guardian, ABC, CNN, New Scientist, E&E $)