Teetering on the Brink: Portions of the Amazon Rainforest Now Emit More Carbon Than They Absorb
The Amazon Rainforest may be nearing – or could have already passed – an irreversible tipping point in its ability to suck carbon dioxide out of Earth’s atmosphere, according to a disturbing new study that was published in Nature on July 14th.
The study was led by scientists at Brazil’s National Institute for Space Research and the US National Oceanic and Atmospheric Administration (NOAA) and “performed 590 aircraft vertical profiling measurements of lower-tropospheric concentrations of carbon dioxide and carbon monoxide at four sites in Amazonia from 2010 to 2018,” according to those involved.
“This carbon sink seems to be in decline, however, as a result of factors such as deforestation and climate change,” the researchers wrote in the study’s abstract. “We find that total carbon emissions are greater in eastern Amazonia than in the western part, mostly as a result of spatial differences in carbon-monoxide-derived fire emissions. Southeastern Amazonia, in particular, acts as a net carbon source (total carbon flux minus fire emissions) to the atmosphere. 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.”
John Miller, study co-author and a scientist with NOAA’s Global Monitoring Laboratory explained in a statement on Wednesday that “the study area, which represents about 20 percent of the Amazon basin, has lost 30 percent of its rainforest.”
The Amazon – often referred to as “the lungs of the planet” – is being systematically razed, mostly for the production of livestock and cheap crops like palm oil, and the pace of destruction has begun to exceed nature’s power to replenish.
Miller stressed that the more trees that are cut down, the more carbon the rainforest releases into the atmosphere.
“Using nearly 10 years of CO2 (carbon dioxide) measurements, we found that the more deforested and climate-stressed eastern Amazon, especially the southeast, was a net emitter of CO2 to the atmosphere, especially as a result of fires. On the other hand, the wetter, more intact western and central Amazon, was neither a carbon sink nor source of atmospheric CO2 , with the absorption by healthy forests balancing the emissions from fires,” said Miller. “The big question this research raises is if the connection between climate, deforestation, and carbon that we see in the eastern Amazon could one day be the fate of the central and western Amazon, if they become subject to stronger human impact.”