Fires raging across the Amazon this summer were not “normal” new research shows, counteracting claims made by the Brazilian government that they were “below the historical average”.
Amazonian fires can occur in a number of ways but there is strong evidence this year’s wildfires were linked to an increase in deforestation, according to the paper published in Global Change Biology Deforestation.
More than 72,000 fires were detected across Brazil between January and August – the highest number since records began in 2013 and an 83 per cent increase on the same period last year.
Deforestation is almost always followed by fire as the cut vegetation is left to dry before being burned.
Scientists found deforestation in July was four times higher than the average in the previous three years. They also found that the number of active fires was three times higher than they were in 2018, reaching their highest levels since 2010.
Professor Jos Barlow, lead author of the paper said: “The marked upturn in both active fire counts and deforestation in 2019 therefore refutes suggestions by the Brazilian government that August 2019 was a normal fire month in the Amazon.”
Researchers used evidence collected from the Brazilian government’s DETER-b deforestation detection system which calculates deforestation by analysing images taken by Nasa.
The fires also occurred at a period when there was not strong drought. They say the ‘enormous’ plumes of smoke that reached high into the atmosphere could only have been caused by the combustion of large amounts of biomass.
Fires decreased by 35 per cent in September and researchers were not clear on whether this was due to President Bolsonaro’s two-month moratoria on fires or not.
Dr Erika Berenguer, a Brazilian researcher jointly affiliated with Lancaster University and the University of Oxford, said: “Our paper clearly shows that without tackling deforestation, we will continue to see the largest rainforest in the world being turned to ashes. We must curb deforestation.
“Brazil has for the past decade been an environmental leader, showing to the world that it can successfully reduce deforestation. It is both economically and environmentally unwise to revert this trend.”
Because it is the world’s largest rainforest, the fate of the Amazon – often called the “lungs of the world” – is widely considered by climate change experts as key to the future of the planet.
It is a vital carbon store that slows down global warming while providing some 20 per cent of the world’s oxygen.
Mr Bolsonaro has systematically weakened institutions designed to protect the rainforest, while offering moral support to farmers wishing to turn the land into cattle ranches.