The Amazon rainforest could soon be reaching a tipping point, according to a new study, with a combination of human-induced pressures such as global warming and deforestation pushing it towards either partial or, in the worst-case scenario, total collapse, by 2050.
“We are approaching a potential large-scale tipping point, and we may be closer (both at local scales and across the whole system) than we previously thought,” said lead author Bernardo Flores, speaking to Agence France-Presse.
To reach this conclusion, researchers took data from computer models and past observations to identify the five key stressors to the world’s biggest rainforest – global warming, annual rainfall, the intensity of rainfall seasonality, the length of the dry season, and deforestation.
They then analyzed these stressors to determine where their individual thresholds that could trigger local, regional, or total collapse might be, and at what point they could combine to produce a “tipping point”, where even a small stress could cause a drastic ecosystem shift.
It was the combination of triggers that the researchers found to be the real kicker; they estimated that by 2050, 10 to 47 percent of the Amazon rainforest would be exposed to enough compounding stresses that it could trigger “unexpected ecosystem transitions and potentially exacerbate regional climate change,” the authors write.
“Compounding disturbances are increasingly common within the core of the Amazon,” Flores explained in a statement. “If these disturbances act in synergy, we may observe unexpected ecosystem transitions in areas previously considered as resilient, such as the moist forests of the western and central Amazon.”
If such a situation occurred, it would not just affect the rainforest itself. The vast swathes of trees in the Amazon act as an enormous carbon sink, which impacts the climate on a global scale. However, with deforestation and climate change, the forest could end up spitting out more carbon than it sinks – something which a 2021 study suggested may already be happening.
This could lead the Amazon rainforest to end up in a particularly vicious cycle.
“We have evidence showing that rising temperatures, extreme droughts and fires are can affect how the forest functions and change which tree species can integrate the forest system,” said study co-author Dr Adriane Esquivel-Muelbert.
“With the acceleration of global change there’s an increasing likelihood that we will see positive feedback loops in which, rather than being able to repair itself, the forest loss becomes self-reinforced.”
The study is published in Nature.
Source Link: Amazon Rainforest Could Face “Large-Scale Collapse” As Soon As 2050