RIO DE JANEIRO – At this time of year, rain should be soaking large swathes of the Amazon rainforest. Instead, a punishing drought kept the rains at bay, creating dry conditions for fires that engulfed hundreds of square kilometers of rainforest that usually don’t burn.
The fires have turned the end of the dry season into a crisis in the northern part of the giant rainforest. Firefighters are struggling to contain massive fires that are sending choking smoke through cities across South America.
A record number of fires in the Amazon so far this year have also raised questions about what to expect in the world’s largest tropical rainforest when the dry season begins in June in the forest’s much larger southern part.
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Last month, Venezuela, northern Brazil, Guyana and Suriname (covering large areas of the northern Amazon) recorded the highest number of fires for February, according to Brazil’s National Institute for Space Research, which has been tracking fires in the rainforest for 25 years. years. Fires also burned in the highlands of Colombia’s Andes and parts of the country’s Amazon territory.
Fires in the Amazon, which have spread across nine South American countries, are the result of extreme drought caused by climate change, experts said.
The region is feeling the effects of a natural weather phenomenon known as El Nino, which could worsen dry conditions that have intensified this year due to extremely high temperatures.
This makes rainforests more vulnerable to fast-spreading fires, said Ane Alencar, scientific director of the Amazon Environmental Research Institute in Brazil.
“Climate is making forests in South America more flammable,” he said. “This creates opportunities for wildfires.”
A challenging fire year is expected around the world as countries continue to burn fossil fuels and the planet reaches the highest average temperatures scientists have ever measured. Severe fires have already ravaged much of the United States and Australia, and a worse season is expected for Canada, where more acres have burned than recorded last year.
Another year of devastating fires could be particularly damaging in the Amazon, which stores large 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 portions of forests could turn to grasslands or weakened ecosystems in the coming decades. Scientists say this would trigger a collapse that could send global carbon emissions into the atmosphere for up to 20 years, dealing a major blow to the fight to control climate change.
Once that tipping point is passed, “it may be useless to try to do something,” said Bernardo Flores, who studies the resilience of ecosystems at the Federal University of Santa Catarina in Brazil.
In January, wildfires burned almost 4,000 square miles of the Brazilian Amazon, according to Mapbiomas, a collective of climate-focused nonprofits and research institutions; This is an almost fourfold increase compared to the same month last year.
More than two-thirds of fires in Brazil in February occurred in the country’s northernmost state, Roraima. They burned homes and subsistence crops in many Native villages, leaving a thick fog in rural areas and creating hazardous air quality in the state capital, Boa Vista.
Alencar explained that as a result of the prolonged drought, the vegetation in this part of the Amazon had become “flammable.” “Roraima looks like a powder keg right now.”
Researchers say many of the fires that have ravaged the region were first started by farmers who used the “slash-and-burn” method to allow new grass to grow on degraded pastures or to completely clear recently deforested land.
Fueled by dry conditions and scorching temperatures, many of these fires get out of control and spread miles beyond the area originally set ablaze.
“Fires are contagious,” Flores said. “They change the ecosystem they pass through and increase the risk to neighboring areas, such as viruses.”
Erika Berenguer, a senior research fellow at the University of Oxford and the University of Lancaster, said fires in Roraima mostly burned areas in the Lavrado, a unique savannah-like region located in the Amazon.
Known for its vast open grasslands and rare wild horse population, this ecosystem overlaps with many protected areas, including the Yanomami Indigenous reserve, where illegal mining and deforestation have led to a humanitarian crisis.
After months of little rainfall, dense rainforests that are often too wet to start fires have also become more susceptible to flames.
In Roraima, fires have now spread to protected forests and Indigenous lands in the southern part of the state, according to Haron Xaud, a professor at the Federal University of Roraima and a researcher at the Embrapa Roraima institute, which monitors the fires.
While fires are common in dry boreal forests in Canada and other parts of the Northern Hemisphere, they do not occur naturally in the much wetter Amazon rainforest. Tropical forests do not adapt to fires and “degrade much more quickly, especially if fire reoccurs,” Xaud said.
Some of the wildfires started by humans in the Amazon have become “megafires,” generally defined as fires that burn more than 100,000 acres of land or have an unusually significant impact on people and the environment. Flores said such fires will become more frequent as the planet warms and deforestation harms the Amazon’s ability to recover.
Environmental factors are already changing the Amazon. Berenguer said dry seasons are lengthening and the average amount of precipitation during these periods, when rains decrease but do not stop completely, has fallen by a third since the 1970s. This has made El Nino increasingly dangerous.
“When all of these factors come together, you have the conditions for a perfect storm, a perfect firestorm,” Berenguer said.
Fires in the Amazon region have had a dramatic impact on carbon emissions. Wildfires in Brazil and Venezuela in February released nearly 10 million tonnes of carbon, according to data from Europe’s Copernicus Atmosphere Monitoring Service; This was the highest figure recorded for that month and approximately equal to the amount Switzerland emits in a year.
The El Niño pattern is expected to end within a few months, providing Amazon with some respite.
However, Alencar said that if the arid land does not receive enough rainfall in the coming critical rainy months, more devastating fires may occur.
“The question is whether the forest can recover before the dry season, whether the Amazon can recharge its batteries,” Alencar said. “Everything depends on the rain now.”
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