Environment: the Amazon rainforest could pass a point of no return by 2050
The Amazon rainforest has been able to resist climatic variations for 65 million years. But today, his destiny risks changing. In an article published in the journal
Nature
, scientists sound the alarm: by 2050, up to 47% of the world's largest tropical forest could reach a point of no return and transform into steppe .
The deforestation of the Amazon forest is financed in particular by French banks, according to a study by several NGOs. © Edmar Barros / AP
By: RFI Follow
Advertisement
Read more
More than a third of what remains of
the Amazon rainforest
is degraded by human activities, but also, and increasingly, by the effects of
ongoing
climate change
, such as recent recurring droughts. Throughout the forest, which extends across nine countries in South America, scientists are recording an increase in the mortality rate of trees, a sign in particular of water stress which could “
trigger the collapse of the forest
”, warn the authors of the study.
Under the pressure of “
hotter temperatures
”, “
extreme droughts
”, “
deforestation
”, and “
erosion
”, up to half of the Amazon would thus reach a “
"breaking
point
", leading the forest into a vicious circle synonymous with a potential collapse of ecosystems.
The Amazon is home to phenomenal biodiversity
“
We
may be closer to this breaking point than we previously thought ,” said lead author Bernardo Flores of Santa Catarina University in Brazil. The consequences of such a scenario would be felt around the world. The Amazon rainforest is home to more than 10% of the world's biodiversity. It stores 200 billion tonnes of carbon, the equivalent of fifteen years of global emissions. It also supplies water to many neighboring countries and cools the entire planet.
To arrive at this observation, Bernardo Flores and his colleagues analyzed five critical factors: global warming, annual precipitation, the intensity of the seasonality of precipitation, the length of the dry season and
deforestation
.
To carry out this study, the researchers relied on paleontological archives (covering approximately 65 million years), climate models and observational data collected since the 1980s, such as satellite observations of the spread of wildfires. forest, tree cover and deforestation. Their findings complement those of the World Weather Attribution Network, which estimated in January that climate change has made
the devastating drought
that hits the Amazon in 2023 30 times more likely.
Avoiding the point of no return
The study identifies three trajectories of permanent evolution of the forest. It could become degraded forests in places, with fewer species, more lianas and bamboo, or open forests, with smaller trees interspersed with invasive grasses, or even a form of savannah. From being a “carbon
sink
”, the Amazon risks becoming an “emitting
source
”, scientists also fear.
But researchers insist it is not yet too late to avoid the point of no return. The study highlights three avenues for remedy: the global reduction of greenhouse gas emissions,
the end of deforestation
and the restoration of degraded territories.
(and
with
AFP)
Also listen How do the oil industry and environmental struggles coexist?
Newsletter
Receive all the international news directly in your inbox
I subscribe
Follow all the international news by downloading the RFI application
Share :
Continue reading on the same themes:
Environment
Climate change
Climate
Amazon