In 2010-2024, Brazil's Amazon emitted an annual average of 1.17 billion tons more carbon dioxide than it absorbed, according to a study published on Thursday by the Sao Paulo Research Foundation.
The imbalance is adding to global warming and eroding the rainforest's role as the planet's most important tropical climate regulator.
The study, also published in the British scientific journal Nature, showed fires released approximately 1.47 billion tons of carbon dioxide annually, compared to an absorption capacity of about 300 million tons per year.
The research, led by specialists from Brazil's National Institute for Space Research (INPE), revealed that drastically reducing fires, eliminating deforestation, and restoring forests are essential to preventing the Amazon from reaching a "tipping point," the threshold beyond which it would lose the ability to sustain itself and recover as a tropical rainforest.
Brazil is home to 60 percent of the Amazon rainforest.
"The main conclusion of the research is striking: the problem in the Amazon is human activity. We are losing the rainforest because the region's development model has been based on destruction," said Luciana Vanni Gatti, coordinator of the Greenhouse Gas Laboratory at INPE and the study's lead author.
In an analysis spanning 46 years, the research team also detected an increase of 1.13 degrees Celsius in the average annual temperature and 1.81 degrees during the dry season. These changes reduce regional humidity and worsen conditions that favor fire spread and environmental degradation.
"This places immense stress on the remaining forest," Gatti said, explaining that the loss of forest cover reduces rainfall and raises temperatures, creating a feedback loop that fuels more fires and speeds up the deterioration of the remaining forest.
Scientists are investigating why the rainforest is absorbing progressively less carbon, and the extent to which this phenomenon is driven by a reduction in photosynthesis versus an increase in the decomposition of vegetation.
The Sao Paulo Research Foundation believes these results reinforce the importance of conservation and restoration policies for the Brazilian Amazon, whose role in carbon storage and the regulation of the water cycle is key to regional and global climate balance.
