Wildfires devastated Brazil and the world in 2024. A study published on Wednesday (21) by the World Resources Institute (WRI) shows the scale of the disaster: for the first time since monitoring began, in 2021, fires – and not agriculture – were the main cause of tropical forest loss across the planet, ing for almost half of all destruction. The world has lost 30 million hectares of forest, an area the size of Italy. In Brazil, data indicate the worst fire-related devastation in seven decades.
“This marks a drastic change from recent years, when fires ed for an average of just 20% [of forest devastation],” warns the institute.
As a result of this tragedy, there has been a significant increase in carbon dioxide (CO₂) emissions, the main cause of the global warming.
Globally, wildfires emitted 4.1 gigatons of greenhouse gases last year. In comparison, Brazil emitted 2.3 gigatons of CO₂ in 2023 considering all emission sources, such as deforestation, wildfires, transportation, and industrial activities, among others.
A large part of these emissions result from fires in tropical forests, such as the Amazon, a biome that saw a 13% rise in the area burned compared to 2023.
The loss of tropical forests alone has devastated 6.7 million hectares, an area the size of Panama and almost double that recorded in 2023. In these areas, wildfires consumed 18 soccer fields per minute.
The greatest loss of tropical forests has been recorded precisely in Brazil, which ed for 42% of all devastation of this type of vegetation in the world by 2024.
The wildfires in these areas are a wake-up call for experts. They indicate a change in how these biomes behave. “Once these forests have been burned, they become more susceptible to burning again,” warns Ane Alencar, director of science at the Amazon Environmental Research Institute (IPAM, in Portuguese).
While regions like the Cerrado biome and the Pantanal (also known as Brazilian wetlands) have part of their vegetation adapted to seasonal fires, tropical forests undergo profound changes when burned, and their regeneration can take a long time. “The recovery process takes a long time because fire is not part of these ecosystems,” says Alencar.
Although wildfires increase CO₂ emissions, they are not ed for by the methodology applied by the Intergovernmental on Climate Change (IPCC), which organizes regular scientific assessments of climate change, its implications and possible risks. “Because these fires are assumed to be part of a natural cycle,” explains David Tsai, coordinator of the Climate Observatory’s Greenhouse Gas Emissions Estimating System (SEEG).
However, in a scenario of large fires in areas where they are not part of the biome’s cycle, the balance between gas emissions and forest regeneration could be compromised, as Tsai points out. “It may be that this assumption adopted in national inventories, which is the IPCC’s recommendation, may no longer be acceptable due to the magnitude.”
“We’re not reporting it, but these emissions are going into the atmosphere (…) Not only Brazil, but other countries should be very concerned about this,” warns Alencar.
In addition to emissions, forest loss has an impact on the goal of reducing deforestation. To reduce forest loss by 2030, the world must reduce deforestation by 20% every year, starting immediately. In contrast to this proposal, in 2024, there had been an 80% increase in the loss of primary tropical forests. Primary vegetation is vegetation that has never been devastated.
“The loss of primary forest from other causes has also increased by 13%, mainly due to large-scale agriculture for soy and cattle raising, although this is still lower than the peaks seen in the early 2000s and during the Bolsonaro years,” the study points out.
“If this trend continues, it could permanently change natural areas and emit large amounts of carbon, intensifying climate change and fueling even more extreme wildfires,” points out Peter Potapov, professor and researcher at the University of Maryland.
The data on global fires are the result of studies by researchers from the Glad Laboratory at the University of Maryland and have been made available on WRI’s Global Forest Watch (GFW) platform.
Gas emissions need to fall
In 2024, fires in Brazil resulted in the emission of 718 megatons of CO₂, considering all types of vegetation affected by fires. Of these, 553 are the result of fires in primary forests. In 2023, emissions from fires in the country amounted to 191.9 megatons of CO₂.
Signed in 2015, the Paris Agreement proposes that countries reduce emissions so that the global temperature does not exceed an increase of 1.5 degrees Celsius.
“The recent IPCC reports already show us that we’re not moving as necessary towards this scenario,” warns Mariana Oliveira, Director of the Forests and Land Use Program at WRI Brazil. “So, we need not only to fight deforestation and advance environmental restoration, but also pay attention to the forest that is standing, what we’re restoring and the forest that has been degraded, so that it doesn’t burn again,” she says.
Even with the high CO₂ emissions, 2024 does not sur 2016 data, when forest fires in Brazil released 825.7 million tons of greenhouse gases into the atmosphere. That year, the country broke deforestation records and, like in 2024, suffered the effects of El Niño.
“It was more extensive than El Niño last year, which only lasted a year. In this case [in 2019], it lasted two years,” explains Alencar.
Optimistic outlook for 2025
The first sparks of the historic wildfire seen in 2024 date back years. The El Niño phenomenon of 2023, characterized by the warming of the Pacific Ocean, reduced rainfall in the Amazon, causing a dry summer in the region that year.
The drought found a biome already devastated by deforestation accumulated between 2016 and 2022, when Brazil hit high rates of native vegetation loss.
The 2025 period of droughts and fires in Brazil is approaching, beginning in the middle of the year. However, the absence of El Niño and the drop in deforestation in all Brazilian biomes last year provide a glimmer of optimism.
For Alencar, it is possible to expect a year with fewer wildfires. “If we improve the control of it, continue to reduce deforestation, have some control over the use of fire in agricultural practices and control crime-related uses of fire, we will certainly have a chance of reducing it a lot,” he says.
For Mariana Oliveira, “Brazil has advanced under the Lula government, but the threat to forests remains. Without sustained investment in forest fire prevention, stricter enforcement in the states and a focus on sustainable land use, hard-won achievements run the risk of vanishing. As Brazil prepares to host COP30, it has a powerful opportunity to put forest protection at the forefront of the global stage.”
