When we destroy the forest, we are not just losing trees. We are changing the climate that the remaining trees need to survive.
Deforestation and human-caused fires are turning the Amazon into a major source of carbon emissions, new research reveals.
As droughts intensify, the consequences for the forest, its people and the global climate are becoming difficult to ignore.
The Amazon is losing its ability to absorb the carbon dioxide we continue to pump into the atmosphere. At the same time, its destruction is disrupting rainfall, intensifying droughts and making vast areas more vulnerable to fire.
Deforestation
For the millions of people who depend on the forest, these changes are already affecting everyday life. But what happens when a forest that helps regulate the climate becomes a growing source of the emissions driving global warming?
New study published in Nature, led by Brazilian scientist Luciana Gatti of the National Institute for Space Research (INPE), provides a disturbing answer.
After 15 years of measuring gases in the atmosphere above the Amazon, researchers found that human activities, particularly deforestation and fires, are responsible for most of the region’s carbon emissions. Extreme droughts make the damage worse, but they are not the main cause.
Using small aircraft, Gatti and her colleagues collected atmospheric measurements across four areas of the Brazilian Amazon. They compared carbon measurements with records of deforestation, burned areas, rainfall and temperature to understand what was driving the changes. The differences between the years are revealing.
During the wetter years of 2011-2014 and 2017-2018, annual deforestation averaged 6,389 square kilometres, while fires affected 55,115 square kilometres of vegetation. The region’s net carbon balance was relatively low, at 0.11 petagrams (PgC) of carbon annually.
Destruction
Between 2019 and 2022, deforestation almost doubled to 12,580 square kilometres, while burned areas increased by 25 per cent to 68,747 square kilometres. Net carbon emission rose sharply, reaching approximately 1.58 billion tonnes of CO2 annually.
But these were not even years of exceptional drought. Temperatures remained close to those of the wetter period, and rainfall was only moderately lower.
The forest was releasing substantially more carbon mainly because more of it was being destroyed.
During three consecutive La Niña years, from 2020 to 2022, increased rainfall helped the Amazon absorb more carbon, partly offsetting emissions caused by deforestation and forest damage.
Gatti explained that without this extra rainfall, the impact of the destruction would have been much worse.
Extinguished
She said: “If we removed the effect of La Niña, emissions would have been much higher. Deforestation was increasing, forest degradation was increasing, and emissions should have increased too. But at the same time, the forest was absorbing more carbon because of those three consecutive La Niña years.”
When we destroy the forest, we are not just losing trees. We are changing the climate that the remaining trees need to survive.
For Gatti, the findings expose the consequences of weakened environmental protections during the government of former Brazilian president Jair Bolsonaro.
The situation became worse during the drought years of 2010, 2015, 2016, 2023 and 2024. Burned areas reached 105,819 square kilometres, almost twice the level recorded during wetter years, while annual net emissions climbed to 1.8 billion tonnes of CO2.
The study found that around 98 per cent of fires were associated with human activity.
Drought made the vegetation easier to burn, allowing fires to spread further and become more destructive. And the consequences don’t disappear when the flames are extinguished.
Impossible
Over the past 46 years, annual rainfall across the Amazon has declined by eight per cent, while rainfall during the peak of the dry season has fallen by 20 per cent. Average temperatures have increased by 1.3c, rising by 1.8c during the driest months.
These changes are altering the conditions that allow a tropical rainforest to survive. Trees weakened by heat and water shortages become more vulnerable to fire and death.
For Gatti, the most alarming evidence comes from the southeastern Amazon, particularly parts of Mato Grosso and southern Pará. The region has already lost approximately a third of its forest, while rainfall during the driest months has fallen by roughly a third and temperatures have risen by 2.2°C over the past 46 years.
She points to the extraordinary length of recent dry seasons as evidence of how hostile the conditions are becoming for trees adapted to a humid tropical climate.
Gatti said: “In 2015, this region experienced seven months of dry season. That is practically impossible for the trees of a humid tropical rainforest. One of the conditions they need is for the dry season to be shorter than the rainy season.”
Decomposition
The consequences may last for years. Gatti suspects that many trees died during these prolonged droughts and that their decomposition continues releasing carbon into the atmosphere.
But there is another possibility, one with far more serious implications for the future of the forest.
Since the severe El Niño event of 2015–2016, the southeastern Amazon has remained a source of carbon even when emissions directly associated with fires are excluded.
Gatti fears this could indicate that the region is approaching, or may already have crossed, a threshold beyond which recovery becomes increasingly difficult.
She explained: “This could be an indication that the region may have already reached the point of no return. But we cannot say that for certain.
"Another hypothesis is that so many trees died during the severe droughts that their decomposition is still releasing carbon, therefore indicating the possibility that the point of no return has not yet been crossed.”
Consequences
Gatti stresses that more research is needed to determine whether the forest is still recovering from past droughts or has undergone a more lasting change. Additional measurements associated with photosynthesis may help answer that question.
What makes these findings particularly disturbing is that the destruction does not end when a tree is cut down. Deforestation also changes the climate of the surrounding forest, creating a second, less visible wave of damage that threatens trees still standing. Gatti explained:
“Deforestation means the death of the forest in two different ways. The first is the direct destruction that everyone counts. The second, which almost nobody counts, is the impact on the climate caused by the loss of the forest itself.
“Every tree is a rain factory. It helps produce rainfall and keeps temperatures down. When we destroy the forest, we are not just losing trees. We are changing the climate that the remaining trees need to survive.”
For communities along the Amazon’s rivers, the consequences are much more immediate than any discussion about carbon balances.
Influence
When water levels fall, boats cannot always reach isolated communities. Food, fuel and medicine become more difficult to transport. Fishing families struggle as river conditions change, while farmers face unpredictable rainfall and longer dry seasons.
Smoke from the forest fires can spread across enormous distances, affecting air quality in towns and cities as well as remote communities. Children, older people and those with respiratory illnesses are particularly vulnerable.
For Indigenous peoples and traditional communities, the loss goes beyond livelihoods. Their territories hold generations of knowledge about the forest, its plans, animals and waterways. When these places are damaged, cultural practices and relationships with the land are threatened alongside the ecosystems themselves.
And the damage goes beyond the Amazon. Moisture released by the rainforest helps generate much of South America, sustaining agriculture, rivers and water supplies.
To illustrate the extraordinary influence of the rainforest on the climate, Gatti points to the enormous volume of water its trees release into the atmosphere every day.
Confined
She explained: “Every day, the Amazon rainforest releases into the atmosphere an amount of water comparable to what the Amazon River discharges into the Atlantic Ocean.
"This is an enormous process in the planet's energy and water balance. It affects the entire Earth system, not just the Amazon or Brazil. But we are the first to suffer the consequences.”
When trees disappear, less moisture returns to the atmosphere, disrupting rainfall and making remaining forest more vulnerable to drought.
Globally, the loss of the Amazon’s capacity to absorb carbon means more greenhouse gases accumulating in the atmosphere, adding to the warming that makes future droughts more severe.
What’s happening in the Amazon will not remain confined to the Amazon.
Destroy
Large areas of the Amazon have been cleared for cattle ranching, agriculture, mining and other commercial activities. Roads open previously inaccessible forest to further occupation, while fires are used to clear vegetation and prepare land of other uses.
These activities have generated vast wealth, but the environmental and social costs are left to the communities living closest to this destruction.
Gatti is particularly critical of the political decisions that have allowed this to continue. She argues that the weakening of environmental protections under former Brazilian president Jair Bolsonaro contributed to rising deforestation and forest degradation. But she also warns that the methods used to destroy the forest are changing.
Although Brazil strengthened its policies against deforestation in 2023 and 2024, Gatti says fire is increasingly being used as an alternative way to clear land, threatening to undermine those gains.
She warned: “If we do not change our policies to combat fires, we will lose the Amazon to fire. I would say that fire is the new deforestation. Fire is being used as a tool to destroy the forest.”
Pollution
Her concern is specifically with fires deliberately used to destroy vegetation, rather than controlled burning for land management. She argues that authorities must impose stronger penalties and prevent illegally burned land from being commercially exploited.
Meanwhile, much of the international discussion about protecting the Amazon now revolves around a bioeconomy, carbon markets, biodiversity credits, conservation finance and investment opportunities.
There is no question that the region needs investment, as communities need healthcare, education, transport, reliable energy and economic opportunities. Conservation cannot mean expecting people to remain poor just because they live near a forest the rest of the world wants protected.
But turning the Amazon into a source of environmental assets raises another question: who will control the benefits?
Gatti questions whether the growing enthusiasm for carbon markets is distracting attention from the more urgent task of reducing emissions. She is particularly critical of schemes that allow companies to compensate for their pollution by paying to protect forests that already exist.
Greenwashing
In her view, preventing the destruction of an existing forest does not automatically create new carbon absorption that can justify additional emissions elsewhere.
“It is misleading to say that someone can emit more carbon simply because we have decided not to destroy a forest. That forest was already there. We have not created any additional carbon absorption to justify those emissions.”
She draws a distinction between protecting existing vegetation and restoring land that has already been cleared. In her view, genuine carbon removal through forest restoration is fundamentally different from claiming credits for leaving an existing forest standing.
Her scepticism also extends to the wider green economy. Gatti fears that environmental promises can conceal commercial activities that continue damaging natural ecosystems, particularly when forests are replaced by plantations promoted as sustainable alternatives.
“I have serious concerns about this green economy because there is so much greenwashing involved. People are destroying forests to establish monocultures of something that is supposed to be green.”
Absorb
For Gatti, a genuinely sustainable Amazonian economy should be built around activities that support both the forest and the people living within it, including forest products, fruits, seeds and ecotourism.
Protecting the Amazon will also require stronger enforcement, political commitment and meaningful participation by Indigenous peoples and traditional communities in decisions affecting their territories.
Wealthy countries must also reduce their own emissions rather than relying on forests elsewhere to compensate for continued fossil fuel use.
The Amazon’s importance to the global climate is enormous. Its vegetation and soils store large amounts of carbon stored for centuries and the rainforest helps regulate rainfall and temperature across the entire continent.
Losing more of that forest would release additional carbon while reducing the amount the remaining vegetation can absorb.
Promises
Gatti’s latest findings show that the Amazon’s future is being shaped not only by a changing climate, but by choices made today.
After decades studying the region, she is frustrated that so much of the environmental debate continues to focus on ending deforestation without recognising that the damage already inflicted on the forest also needs to be repaired.
“What makes me desperate is that so many people still believe that achieving zero deforestation is the solution. There is enormous difficulty in getting science through to the people making decisions.”
For Gatti, the scale of the crisis demands more than existing conservation commitments.
She believes governments should treat the destruction of the Amazon as an immediate emergency rather than a problem to be addressed through distant targets and promises.
Irreversible
She urged: “We need zero deforestation now and an extremely intensive programme of forest restoration. A state of emergency should be declared in the Amazon. We cannot afford to lose it. Everything is connected, and the consequences go far beyond the Amazon or Brazil.”
Her frustration is not confined to the scientific community. Gatti believes that researchers have spent decades producing evidence of the dangers facing the Amazon, yet too much of that knowledge has failed to influence political decisions. That failure has become personal.
“There is an enormous difficulty in getting science through to the people making decisions. Even in a progressive government, that is a problem. This is why I decided to go into politics.”
The Amazon needs deforestation and fires to stop, damaged areas to have a chance to recover and the people who depend on the forest to have a genuine say in its future.
The science has identified the causes of this destruction. The question now is whether governments are prepared to confront them before the damage becomes irreversible.
This Author
Monica Piccinini is a Brazilian-British journalist and a member of the National Union of Journalists. She is a regular contributor to The Ecologist and publishes on Substack, Medium and on her own platform, YourVoiz.org.
