[ad_1]
The Amazon is approaching a tipping point, data shows, after which the rainforest would be lost with “profound” implications for the global climate and biodiversity.
Computer models had previously suggested that a mass dieback of Amazonia was possible, but the new analysis is based upon real-world satellite observations over three decades.
A new statistical analysis has shown that more than 75% untouched forest has lost stability over the past 20 years, which means that it takes longer to recover from wildfires and droughts.
The most severe loss of stability occurs in areas near roads, farms, and cities. It is also more common in regions that are becoming dryer, suggesting that global warming and forest destruction are the causes. These factors “may already have pushed the Amazon close to a critical threshold of rainforest dieback”, the scientists conclude.
The study cannot predict when the tipping point will be reached. Researchers warned that it would be too late for them to stop the tipping point being triggered.
Once activated, the rainforest would turn to grassland in a few years, releasing enormous amounts of carbon, and accelerating global warming further.
Climate scientists are concerned about tipping points on a global scale. They are irreversible and are one of the most frightening fears. The same statistical technique was used to reveal the same results in 2021. Warning signs of the Gulf Stream’s collapse and other key Atlantic currents, with “an almost complete loss of stability over the last century”.
These currents could shut down and cause catastrophic damage around the globe, disrupting monsoon rains as well as threatening Antarctic ice sheets.
Another study revealed that a large part of the The tipping point for the Greenland Ice Sheet is nearThis would result in a 7 m sea level rise over time.
“Many researchers have theorised that an Amazon tipping point could be reached, but our study provides vital empirical evidence that we are approaching that threshold,” said Prof Niklas Boers, at the Technical University of Munich in Germany.
“Seeing such a resilience loss in observations is worrying. The Amazon rainforest stores huge amounts of carbon that could be released in the case of even partial dieback.”
The scientists said Amazon dieback had “profound implications at a global scale”. Boers added: “The Amazon is definitely one of the fastest of these tipping elements in the climate system.”
The research Published in Nature Climate Change, analyzed satellite data on the amount and distribution of vegetation in more that 6,000 grid cells throughout the unspoiled Amazon between 1991 and 2016.
The researchers found that areas affected by droughts and fires have taken longer to recover over the past 20-years. This is a sign that the restoration process is becoming less efficient.
Wetter forests lost more stability in the dry areas than those in the wetter areas. “This is alarming, as the IPCC [Intergovernmental Panel on Climate Change] models project an overall drying of the Amazon region in response to global warming,” Boers said.
The forest areas closer to human destruction also became more unstable. Rain is produced by trees, so it is important to remove them from the land. Beef Soy productionThis creates a vicious circle of tree loss and drier conditions.
Another study in 2021 was based upon data from hundreds of small-plane flights and showed that the Amazon emits more carbon dioxide now than it absorbsFires are the main reason.
But Boers said the data indicated that the tipping point has not yet been crossed: “So there’s hope.” Prof Tim Lenton at Exeter University in the UK, a co-author of the study, said: “It supports efforts to reverse deforestation and degradation of the Amazon to give it back some resilience against ongoing climate change.”
Chris Jones, at the Met Office Hadley Centre in the UK, and not part of the study team, said: “This research adds compelling evidence that climate change is a risk now, and that these severe and irreversible impacts could become a reality. We have a limited window of opportunity to act quickly.
“The worrying conclusion [of the study]This is in line with other recent research that has shown increased tree mortality, increased fires and reduced regional carbon sinks. The IPCC report out last week assessed that risks of large scale singular events, such as Amazon dieback, are now closer than ever.”
Bernardo Flores, at the Federal University of Santa Catarina in Brazil, said: “The study shows that although the forest may seem fine, with its normal structure and biodiversity, internal processes are already changing, silently, reducing the system’s capacity to persist in the long run. The approach used is interesting because it reveals early warning signals of these changes.”
Flores’s research revealed that Amazon savannas were expanding in the heart of the AmazonWildfires.
The government of Brazil’s president, Jair Bolsonaro, has been harshly criticised for encouraging more deforestationThe highest level since 2006 was attained by, which rose 22% in November.
Boers said: “It’s really complicated to say what’s going to be first: reaching a tipping point by [loss of stability] of the natural vegetation system, or just the bulldozers reaching the forest.”
[ad_2]
