In a study published Wednesday, Brazilian researchers highlight that the Amazon rainforest is on the verge of reaching a crucial tipping point by 2050. The finding is alarming and could have devastating consequences for both the region and for the world’s ability to combat climate change.
The Amazon rainforest has demonstrated resilience in the face of natural climate change for 65 million years. However, deforestation and the human-caused climate crisis have led to new levels of stress that could cause a large-scale collapse of the forest system within the next three decades, according to the study.
According to the researchers, between 10% and 47% of the Amazon would be exposed to stressors that could lead the ecosystem to this tipping point, a critical threshold beyond which a downward spiral of impacts would be inevitable.
This study, led by researchers at the Federal University of Santa Catarina in Brazil and published in the journal Nature, takes a holistic approach to estimate when the Amazon could reach this critical threshold.
The study authors looked at the impact of high temperatures, extreme droughts, deforestation and fires to reach their conclusions.
“We already knew about all these factors at play, but once we managed to put all the pieces of this complex puzzle together, the picture was alarming,” Bernardo Flores, lead author of the study, told CNN. “Our results revealed how the Amazon forest system could enter a phase of self-reinforcing collapse sooner than expected.”
Previous studies had not predicted a collapse of this scale during the 21st century.
A collapse of the Amazon, the world’s largest rainforest, would weaken its ability to absorb carbon emissions that contribute to global warming. Once considered the “lungs of the planet,” the Amazon is now a net emitter of greenhouse gases, releasing more carbon into the atmosphere than it absorbs. Fires and logging are the main causes of this change.
However, the forest remains a huge, crucial carbon sink. It contains the equivalent of 15 to 20 years of global carbon reserves.
The study also shows how deterioration in the Amazon could impact forests in other parts of South America.
The Amazon is vital to the water supply of the entire region, contributing up to half of the precipitation through what researchers call “flying rivers” – rain that originates above the Amazon and spreads to other parts of the region. This allows other forests and ecosystems that rely on rain to thrive. Among these places are the Pantanal wetlands – the world’s largest tropical wetlands spanning Brazil, Bolivia and Paraguay – and the La Plata River watershed, a crucial, biodiverse water system that drains a fifth South American lands.
The Amazon also provides moisture beyond the region.
“The Amazon rainforest is a major pump of moisture into the atmosphere, contributing to circulation processes that transfer moisture across the globe,” Flores explains. “When the forest decreases, it weakens this process, which disrupts the global climate and pushes it to find a new equilibrium.”
The study authors noted that water stress was a common factor in disruptions in the Amazon. Water stress occurs when available water is not sufficient to meet human or ecological needs.
Global warming intensifies the effects of water stress by making the Amazonian climate drier and hotter. This worsens water stress on trees, especially those with low drought resistance in the northwestern parts of the forest, which “could suffer mass mortality if suddenly exposed to severe water stress,” according to the ‘study.
Reaching this tipping point could also make parts of the Amazon uninhabitable due to unbearable heat and a lack of resources for indigenous people and local communities, the study shows.
“A war of attrition is being waged against the Amazon rainforest through human-caused climate change and deforestation, pushing this irreplaceable jewel of the planet to the brink,” says Richard Allan, professor of climatology at the University of Reading, which was not involved in the study. “These critical effects… are compounded by the continued destruction of forests for agriculture, settlement and industry.”
The study recommends ending deforestation, promoting forest restoration and expanding protected areas and indigenous territories. Flores also highlights the need for global cooperation to reduce greenhouse gas emissions and emphasizes the importance of cooperation among Amazonian countries to promote forest restoration.