THE AMAZON CREATES MORE GREENHOUSE GASES THAN IT ABSORBS
Forests absorb carbon dioxide (CO2) from Earth’s atmosphere, making them a key part of mitigating climate change. But humans may have already rendered the world’s largest rainforest useless in the battle against greenhouse gases. The Amazon is now emitting more than 1 billion tonnes of CO2 a year, meaning the forest is releasing more carbon into the atmosphere than it’s removing.
The carbon balance tipped due to “large-scale human disturbances” in the Amazon ecosystem, researchers wrote in a study, with wildfires – many deliberately set to clear land for agriculture and industry – responsible for most of the CO2 emissions from the region. These fires also reinforce a feedback loop of warming, the team found, with more greenhouse gases contributing to longer, hotter dry seasons in the Amazon, which lead to more fires and more CO2 pollution.
The eastern Amazon in particular, which has seen historically greater amounts of deforestation over the past 40 years, has become hotter, drier and more prone to fires than the rest of the rainforest. The result is greater amounts of greenhouse gas emissions from the region and fewer trees to suck up the carbon again through photosynthesis.