Data provided for more than a decade by two Earth surveillance satellites launched by the NASA confirm what had been suspected for some time. The rains have decreased in the Amazon, causing a significant loss of vegetation cover. This not only affects biodiversity, but has global implications, as the Amazon rainforest stores less carbon, which further contributes to global warming. Without the capacity to absorb it, this carbon returns to the atmosphere, worsening climatic conditions and further reducing rainfall in the region.
The impact of climate change on the Amazon
The Amazon, known as the “lungs of the planet,” has been a crucial carbon dioxide (CO2) sink due to its vast size and forest density. However, over the past decade, the Amazon has begun to show an alarming shift in behavior, shifting from a carbon sink to a carbon source, emitting more CO2 than it absorbs. This phenomenon is largely due to two main factors:
- Deforestation:The felling of trees for agriculture and livestock is one of the main causes of the loss of the Amazon's capacity to absorb carbon.
- Forest fires:These fires, whether caused or natural, are devastating millions of hectares of forest, releasing large amounts of carbon stored for centuries.
According to recent studies, southeastern Amazonia is one of the most affected areas, emitting up to three times more carbon than it is able to absorb. This suggests that we are reaching a point of no return for the Amazon, raising serious questions about the future of this biome and its role in regulating the global climate.
Rainfall and the water cycle in the Amazon
Another key aspect that has been disrupted by global warming and deforestation is the Amazon’s water cycle. The rainforest is responsible for generating a large amount of its own rainfall by releasing vast amounts of water into the atmosphere through plant evapotranspiration. These “flying rivers” are critical not only to the Amazon region, but also to other parts of South America. The disappearance of this moisture could cause extreme forest droughts, directly affecting agriculture and water supplies in nearby areas.
Key research on carbon loss in the Amazon
Over the past few years, a number of studies have been carried out that have highlighted the seriousness of the situation. Recent studies have shown that around 20% of the forest has been cut down or degraded since the 70s. By 2019-2020, the Amazon was already emitting more than it was capturing. In fact, some studies have documented that carbon emissions in some regions, such as the southeastern Amazon, are up to 10 times higher than in others.
One of the most significant studies was carried out by Luciana Gatti of the Brazilian Space Institute (INPE), who used airplanes to take air samples over different parts of the Amazon. This study confirmed that the rate of deforestation on the eastern side is significantly higher than on the western side, which is causing this part of the Amazon to be a net emitter of carbon. Changes in rainfall patterns and extreme temperatures are drastically affecting trees, which means that more and more carbon will be released into the atmosphere.
Using NASA's Terra and Aqua satellites has allowed researchers to monitor these changes in detail. Terra has been used primarily to study vegetation cover, while Aqua has focused on the water cycle, providing an overview of how climate change is affecting the Amazon's ability to function as a carbon sink.
Current threats: climate change and deforestation
Climate change and deforestation are putting combined pressure on the Amazon. Prolonged droughts, partly caused by phenomena such as El Niño, are making conditions increasingly hostile for vegetation. Deforestation, meanwhile, has transformed vast tracts of forest into agricultural or grazing land, significantly reducing the Amazon's capacity to absorb carbon dioxide.
According to several studies, reaching 20% deforestation in the Amazon could be the point of no return. Surpassing this threshold would likely trigger a collapse of the Amazonian ecosystem, transforming the rainforest into a dry savannah. This would release tens of billions of tons of carbon, further driving global warming.
The role of indigenous peoples in carbon conservation
One of the positive elements in the fight against carbon loss in the Amazon is indigenous peoples. Lands managed by indigenous communities have been shown to have much lower rates of deforestation and forest degradation. In fact, indigenous forests in the Amazon have been important carbon sinks, capturing millions of tons of CO2 per year.
A recent study found that 58% of the Amazon's biomass is located within indigenous territories and protected areas. These territories have been instrumental in preventing global warming from becoming even more severe, due to their ability to hold carbon reserves. In comparison, lands outside these areas suffer much more from deforestation.
Conservation policies implemented on indigenous lands are a clear example of how rainforest protection could be expanded. However, indigenous peoples are increasingly facing external pressures such as illegal mining, logging and territorial conflicts. These factors put at risk the ability of these communities to continue protecting the Amazon.
The situation in the Amazon is serious and complex. The interactions between deforestation, climate change and socioeconomic factors are bringing this crucial ecosystem to the brink of collapse. Measures are urgently needed, both locally and globally, to protect what remains of this lung of the planet.