Parts of the Amazon rainforest are now emitting more carbon dioxide than they are absorbing, according to a study published by the journal Nature on Wednesday.
Researchers found that parts of the Amazon, which have historically acted as “carbon sinks” — areas that absorb carbon dioxide that is harmful to the environment — have begun to decline. The decline is largely due to deforestation, rising temperatures and reduced rainfall in the dry seasons.
The study found that there were more carbon emissions in the eastern part of the rainforest than the west, as a result of “spatial differences” in “carbon monoxide-derived” fire emissions.
“Over the past 40 years, eastern Amazonia has been subjected to more deforestation, warming and moisture stress than the western part, especially during the dry season, with the southeast experiencing the strongest trends,” the study reads.
The regions affected most by the carbon imbalance have warmed about 4.5 degrees Fahrenheit.
The research was conducted by measuring carbon dioxide and monoxide levels from small planes during about 590 flights over the span of 8 years, between 2010 and 2018.
The Amazon rainforest, located largely in Brazil, is a critical barometer to measure climate change and its impacts on the globe. It remains the world’s largest rainforest, and plays an important part in absorbing carbon from the atmosphere.
In recent years, the Amazon has been subject to massive fires and deforestation and Brazil’s president, Jair Bolsonaro, has received backlash for encouraging more deforestation in the area.
Some scientists have said that the forest has reached a tipping point, at which time the forest will not be able to capture enough carbon to offset emissions. A 2018 essay published in Science Advances and mentioned by The New York Times warned that human destruction of the rainforest could turn the region into a savanna.
“The precious Amazon is teetering on the edge of functional destruction and, with it, so are we,” the essay read. “We stand exactly in a moment of destiny: The tipping point is here, it is now.”
The new study in the journal comes following a wave of scorching heat that has led to dozens of deaths in the Western United States. Climate experts have said that the intense heat experienced in the West would be “virtually impossible” without the effects of climate change.
In addition, the National Oceanic and Atmospheric Administration confirmed that last month was the hottest June on record in the U.S.