An Amazon with fields advancing over the forest, high tree mortality, intense droughts, extreme rains, more frequent forest fires, loss of biodiversity and carbon dioxide emissions greater than the absorption capacity.
All this is already happening, but it tends to accelerate even more if global climate change and the advance of deforestation, both results of human action, are not contained, warns the second volume of the sixth report of the IPCC (Intergovernmental Panel on Climate Change, released this Monday (28).
The Amazon occupies a prominent place in the study, carried out by 270 scientists from around the world. To analyze the situation of the world’s largest rainforest, the IPCC drew on dozens of academic articles on the climate crisis in the region both to describe already verified impacts and to project climate scenarios.
Overall, the IPCC points to an explosive combination between global climate change, caused by the emission of greenhouse gases, and the effects caused by agricultural expansion and the opening of roads, which cause the fragmentation and degradation of the surrounding forest.
“In the Amazon, deforestation exerts an influence on forest fires that could be stronger than climate change,” the report says.
This was the case with the forest fires in Roraima between 2015 and 2016, when the severe drought caused by a “super El Niño”, associated with the increase in roads and deforested areas, caused the biggest fire recorded in this region of the Amazon.
In just a few weeks, the state lost up to 14,000 kmtwoor 9% of its vegetation cover.
These fires have become more frequent in the recent past and are likely to continue to increase, but agricultural-driven deforestation remains the leading cause of tree mortality. Between 1988 and 2020, forest cover reduced an average of 13,900 kmtwo per year in the Brazilian Amazon, according to the report.
The consequence is that, from 2003 to 2008, the Amazon as a whole went from being a “sink” to being an emitter of carbon dioxide, one of the greenhouse gases. In four specific places, the Amazon also presented carbon emissions between 2010 and 2018, due to deforestation and fires.
The report warns that increasing fire, deforestation and drought could lead to the conversion of up to half of the Amazon rainforest to grassland, “a turning point that could release an amount of carbon that would substantially increase global emissions.”
There is a strong link between climate, deforestation, fires and changes in vegetation. The Amazon has already entered a new, warmer and highly variable climate regime, with longer and more intense dry seasons and the severity of droughts altering the fire regime.
“In addition to causing immediate emissions of carbon dioxide, the constant fires induce changes in vegetation, with enormous loss of biodiversity and substantial alteration in its structure, reducing the natural capacity of the forest to store and recycle nutrients. Keeping large areas of intact forest is essential to preserve biodiversity and control fire in the region”, says ecologist Ima Vieira, from the Goeldi Museum, in Belém.
​”The biggest change would be in what the Amazon is today: an eminently forest biome. When changing climatic conditions, the hydrological cycle, humidity and biodiversity, the functionality and survival of the forest are affected. There are already studies showing that the east and south of Pará are on the verge of crossing a critical point that will lead to their rapid conversion into a vegetation formed by shrubs, grasses and medium and small trees”, adds the researcher.
For researcher Flávia Costa from Inpa (National Institute for Research in the Amazon), the possible paving of the BR-319, between Manaus and Rondônia, a work promoted by President Jair Bolsonaro (PL), carries the risk of leading to degradation and forest fragmentation to one of the most intact places in the Amazon. “This is a great danger to the maintenance of the carbon absorption potential”, she says.
On the other hand, Costa states that the effects of climate change are quite heterogeneous on the Amazon, a region with a wide range of environments. According to her, there are other aspects that need further study, such as the role of groundwater in carbon capture, present in 50% of the entire region.
“There are regions with surface water table, still poorly studied, that may be functioning as a carbon sink during droughts, but this has not yet been quantified. My research group is looking into this aspect of the functioning of the Amazon to determine whether this function sinkhole is actually happening.”
Faced with this climate crisis, the policies of the Brazilian State go in the opposite direction of the guidelines that the IPCC report points out, according to Ima Vieira.
“There are no well-defined climate policies in Brazil. We have also seen public policies to control deforestation and fires, agrarian reform, and the management of protected areas being dismantled and/or discontinued”, he says.
“Since 2017, there has been a significant increase in deforestation, illegal occupation of public lands and threats to the integrity of protected areas, especially in the Amazon. All this contributes to the worsening of the climate crisis.”
