by RIO DE JANEIRO — By this time of year, the rain should be drenching large swaths of the Amazon rainforest. Instead, a punishing drought left the rain, creating dry conditions for fires that engulf hundreds of square miles of rainforest that don’t normally burn.
The fires ended the dry season in the northern part of the great rainforest in crisis. Firefighters struggled to contain massive blazes that sent smoke choking South American cities.
A record number of fires so far this year in the Amazon has raised questions about what may happen to the world’s largest tropical rainforest when the dry season begins in June in the south of the much larger jungle.
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Last month, Venezuela, northern Brazil, Guyana and Suriname, which includes large stretches of the northern Amazon, recorded the highest number of fires for any February, according to Brazil’s National Space Research Institute, which has been tracking fires in rain forest for 25. years. Fires also burned across the highlands of the Andes in Colombia, as well as parts of that country’s Amazon region.
The fires in the Amazon, which reach across nine South American nations, are the result of severe drought caused by climate change, experts said.
The region is feeling the effects of a natural weather phenomenon called El Nino, which could make dry conditions worse this year at very high temperatures.
The rainforest is therefore more vulnerable to blazes that spread quickly, said Ane Alencar, scientific director of the Amazon Environmental Research Institute in Brazil.
“The climate is making forests in South America more flammable,” she said. “It’s creating opportunities for wildfires.”
As countries continue to burn fossil fuels and the planet reaches the highest average temperatures measured by scientists, a tough fire year is expected around the world. Severe blazes have already devastated large parts of the United States and Australia, and a worse season is predicted for Canada, where more acres burned last year than ever recorded.
Another year of devastating fires could be very damaging in the Amazon, which stores huge amounts of carbon dioxide in its trees and soil. It is also home to 10% of the planet’s plants, animals and other living organisms.
If deforestation, fires and climate change continue to worsen, large areas of forest could be transformed into grasslands or degraded ecosystems in the coming years. That, scientists say, would trigger a drop that could put up to 20 years’ worth of global carbon emissions into the atmosphere, a huge blow to the struggle to curb climate change.
When this tipping point is crossed, “it might not be useful to try to do something,” said Bernardo Flores, who studies ecosystem resilience at the Federal University of Santa Catarina in Brazil.
In January, wildfires burned nearly 4,000 square miles of the Brazilian Amazon, a nearly four-fold increase from the same month last year, according to Mapbiomas, a group of climate-focused nonprofit organizations and research institutions.
In February, more than two-thirds of Brazil’s fires occurred in Roraima, the country’s northernmost state. They have burned houses and subsistence crops in several Indigenous villages, leaving thick blight over rural areas and creating hazardous air quality in the state capital, Boa Vista.
As a result of the long drought, the vegetation in this part of the Amazon has become “combustible,” Alencar explained. “Roraima is like a barrel of gunpowder right now.”
Researchers say most of the fires that have swept through the region were first started by farmers using the “slash and burn” method to allow new grass to grow on degraded pastures or to clear recently deforested land fully.
Due to the dry conditions and scorching temperatures, many of these fires get out of control, spreading miles beyond the area that was originally burning.
“Fires are contagious,” Flores said. “They change the ecosystem they go through and increase the risk to neighboring areas like a virus.”
In Roraima, the blazes have largely burned areas within the Lavrado, a unique savannalike region located within the Amazon, said Erika Berenguer, a senior research associate at the University of Oxford and Lancaster University.
This ecosystem, known for its wide-open grasslands and rare population of wild horses, overlaps with several protected areas, including the Yanomami Indigenous reserve, where illegal mining and forest destruction have led to a humanitarian crisis .
After months of scant rain, dense rainforest that is normally too wet to catch fire is more vulnerable to flames.
In Roraima, the fires have now spread to protected forests and indigenous lands in the southern region of the state, according to Haron Xaud, professor at the Federal University of Roraima and researcher at Embrapa Roraima, an institute that monitors the fires.
While fires are common in the drier boreal forests of Canada and other parts of the Northern Hemisphere, they do not occur naturally in the much wetter Amazon rainforest. Tropical forests are not adapted to fires, Xaud said, “and they degrade much faster, especially if the fire happens repeatedly.”
Some of the wildfires started by humans in the Amazon have grown into “megafires”, usually defined as blazes that burn more than 100,000 acres of land or have an unusually significant impact on people and the environment. These types of fires, Flores said, will become more frequent as the planet warms and deforestation damages the Amazon’s ability to recover.
Environmental factors are already changing the Amazon. Dry seasons are getting longer, and the average rainfall during those periods, when rain decreases but doesn’t stop altogether, has already dropped by one-third since the 1970s, Berenguer said. So El Ninos are becoming more dangerous.
“When you have all these factors together, you have the conditions for a perfect storm — the perfect firestorm, that is,” Berenguer said.
The fires in the Amazon region have had a significant impact on carbon emissions. In February, wildfires in Brazil and Venezuela released nearly 10 million tons of carbon, the most ever recorded for the month and about as much as Switzerland emits in a year, according to data from the Copernicus Atmospheric Monitoring Service of Europe.
The El Nino pattern should end in a few months, bringing some relief to the Amazon.
But more destructive fires could erupt if the parched soil does not receive enough rain in the crucial wetter months ahead, Alencar said.
“The question is whether the forest can recover before the dry season, whether the Amazon can recharge its batteries,” said Alencar. “It all depends now on the rain.”
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