Recent drying over the Amazon could be the “first warning signal” that the rainforest is approaching a tipping point, new research says.
The Amazon is the largest rainforest in the world and receives 2-3 metres of rain every year. However, intensifying droughts and human-driven deforestation mean parts of the forest are beginning to dry out.
The study, published in Science Advances, finds that deforestation is delaying the start of the South American monsoon, leading to reduced rainfall over the Amazon.
The authors warn that continued deforestation could push the region past a tipping point in which a further, rapid reduction in rainfall would kill vast swathes of trees.
Over the past 40 years, the Amazon’s dry season has already become longer, the paper finds. This might be the early warning signal that the combined rainforest and South American monsoon systems are approaching a critical threshold, the authors say.
The authors also stress the importance of ongoing experimental work to quantify the impacts of increasing temperature and CO2 on the Amazon rainforest, so that scientists can produce more accurate models of the links between deforestation and rainfall.
Amazon water cycle
The Amazon is the largest rainforest in the world.
The region contains around 400bn trees and is home to at least 10% of the world’s known species. It is also a key carbon store, holding more than 120bn tonnes of carbon in its vegetation and soil.
Tropical rainforests are warm and humid all year round. The Amazon basin receives around 2-3 metres of rainfall every year on average. It “recycles” much of this rainfall back into the atmosphere through evapotranspiration – the movement of water from the land to the atmosphere through a combination of evaporation and transpiration.
Much of this rainfall comes from the South American monsoon, which is driven in part by the temperature difference between the warm Amazon rainforest and cooler Atlantic ocean.
However, as droughts become more intense and frequent, the humid Amazon climate is beginning to dry, killing trees or making them less resilient to future changes. The ongoing drying trend is exacerbated by deforestation and wildfires.
Around 20% of the Amazon has already been deforested and a further 6% is “highly degraded”.
Dr David Lapola is a research scientist at the State University of Campinas in Brazil and a Carbon Brief contributing editor. Lapola, who was not involved in the study, tells Carbon Brief that the Southern and south-eastern Amazon are “currently experiencing a crisis in terms of changing climate and land use”.
Scientists have warned for decades that human-caused climate change could push key components of the Earth system – such as ice sheets, rainforests and monsoons – past critical thresholds and into new states.
Identifying these “tipping points” is an active area of research.
Previous studies suggest that the Amazon could be pushed beyond its tipping point if forest loss exceeds 40%. At this level of deforestation, evapotranspiration in the Amazon would reduce significantly, leading more trees to die from lack of water.
This self-perpetuating cycle could see large areas of tropical forest turn into dry grasslands in just decades, in a process called “dieback”.
Deforestation
To investigate the link between Amazon deforestation and rainfall, the study authors produce a model of moisture transport across South America that simulates how air moves through the Amazon. The model includes key feedbacks between vegetation, soil moisture and the atmosphere.
The authors find that deforestation reduces the amount of water released into the atmosphere through evapotranspiration. The drop in atmospheric moisture drives a reduction in rainfall.
To form raindrops, water vapour in the atmosphere condenses into liquid water, releasing energy in the form of heat. The reduction in rainfall means that less energy is released in this way, limiting warming in the atmosphere above the region.
As a result, the temperature difference between the warm Amazon rainforest and cooler Atlantic ocean becomes less pronounced. This can cause delays in the onset of the Amazon’s wet season and a lengthening of the dry season, resulting in drier soils and higher tree mortality.
Overall, this feedback means that deforestation in the Amazon weakens the South American monsoon, further reducing rainfall over the Amazon.
Prof Dominick Spracklen is a professor of biosphere-atmosphere interactions at the University of Leeds and co-wrote a “focus” article on the new study.
He tells Carbon Brief that including this complex feedback between the forest and atmosphere makes the rainforest-monsoon system “more sensitive to deforestation, compared to many previous studies that did not include this feedback”.
The graphic below shows the relationship between deforestation and rainfall. The dashed line shows the model used in the study with all feedbacks included, while the solid line shows a model which does not include the atmosphere-vegetation feedbacks.
The study authors find that if deforestation crosses a “critical threshold”, rainfall could drop by 30-50% over just a few years, pushing the system past a tipping point and damaging or killing large areas of the forest.
The model shows that Amazon rainfall is more sensitive to deforestation when key feedbacks between the atmosphere and vegetation are taken into account. This indicates that the tipping point could be crossed sooner than previously thought, the authors warn.
Dr Nils Bochow – a researcher at the Arctic University of Norway and co-author of the study – tells Carbon Brief that “changes in the South American monsoon have a strong influence on the rainforest and vice-versa”. He adds:
“If we do not include these interactions and feedbacks, then we might strongly underestimate the response of the rainforest. This might give a false sense of security or undermine the urgency to act.”
Early warning signs
If an Amazon tipping point is crossed, large sections of lush rainforest could transform into a dry savannah. This process of “savanisation” would take decades to take full effect, but once underway the process is difficult to reverse. The knock-on impacts for the rest of the planet could be profound.
“Tipping points are notoriously hard to understand or predict,” Spracklen tells Carbon Brief.
However, he says there are often early warning signs when a tipping point is approaching. He likens these to the wobble of a spinning top before it falls over.
After using the models to determine what this “wobble” would look like in the Amazon, the authors analyse decades of ERA5 reanalysis data to search for it.
The map below shows the change in soil moisture between 1979 and 2019. Red indicates a drying trend over the four-decade period, while blue indicates wetting.
The authors find that over 1979-2019, soil in the Amazon has become drier. They also find that the dry season now lasts between five and 15 days longer than it used to – meaning that the region is receiving less rainfall, on average, than it was four decades ago.
This indicates that the monsoon-rainforest system has been losing stability in the last decades, the authors say. This might be the first warning signal that a tipping point is approaching, they add.
“The results of this study underline the need to double down on efforts to stop deforestation and help the Amazon region develop in a way that does not lead to additional deforestation,” Spracklen tells Carbon Brief.
Forest loss in the Amazon is beginning to slow. Deforestation in the Brazilian Amazon fell by at least 60% in July 2023 compared to the same month last year, after a new administration led by Luiz Inácio Lula da Silva took power in Brazil.
Leaders of the eight Amazon basin countries met in August 2023 to agree on the need to sustainably develop while preventing further deforestation in the region, and formally recognised that the Amazon is approaching a tipping point.
Model uncertainty
This study is “one of the first” to simulate the feedbacks between the monsoon and Amazon, according to the study authors.
Bochow tells Carbon Brief that including these “non-linear” components is key, because when small changes “reinforce each other” they can lead to significant impacts.
However, the model is unable to account for everything. Most notably, it does not include the impact of rising CO2 levels or temperatures on the forest. This omission is a notable “gap” in the study, according to Lapola.
He tells Carbon Brief that elevated CO2 levels can have a significant impact on the forest through changing evapotranspiration levels, reducing rainfall and inducing plants to use water more efficiently.
Lapola adds:
“[We should] have more experimental studies, in which we manipulate the ecosystem to test its limits in terms of resilience – for example, testing [the effects of] higher temperature and CO2.”
Spracklen tells Carbon Brief that researchers need more observational data, but warns that observations also have their “limitations”. A combination of observations and models are needed to make better predictions, he says.
Bochow points out that climate models show “a big spread in the response of the Amazon rainforest to climate change and deforestation” and agrees that there is an “urgent need to constrain the models better by doing more field experiments and observations”.
He also emphasises that “the exact numbers of our model are not to be taken for granted”. He tells Carbon Brief:
“The model simulations are used as guidance where to look for characteristic changes of stability loss in observations. Our study really focuses on the observed changes in the historical data and these do not depend on our employed model.”
The post Drying of Amazon could be early warning of ‘tipping point’ for the rainforest appeared first on Carbon Brief.
Drying of Amazon could be early warning of ‘tipping point’ for the rainforest
The United Nations Secretary-General and foreign ministers from the UK, France and Spain have blamed the deadly wildfires engulfing Europe on climate change, using the disaster to renew calls for faster cuts to greenhouse gas emissions.
António Guterres told journalists on Friday that the “climate crisis is in overdrive”, adding that global heat seen so far is just a “warm up act” as a phenomenon known as El Niño intensifies “adding fuel to a planet already on fire”.
A new World Meteorological Organisation (WMO) report published on Friday predicts that the weather pattern will grow into a “strong event” between now and October, increasing the risk of higher than normal temperatures across much of the world and disrupted rainfalls.
“That risks shattering every seasonal record – and driving even more severe effects worldwide,” Guterres said.
El Niño builds on top of an already warming world, driven primarily by the burning of fossil fuels. A WMO scientist, who did not want to be named, told journalists that all the heatwaves and other climate impacts seen so far this year are “before the effects of El Niño are really kicking in at a global scale”.
Fossil fuellling the fires
Fires have broken out across much of Europe but are threatening the most people in the south-west of France near Bordeaux and in Central Spain near Madrid. Nearly a quarter of a million people have been evacuated in France with hundreds of homes destroyed while in Spain 80,000 people have had to leave their homes and at least 13 died in one village.
A scientific study published on Friday by the World Weather Attribution group found that man-made climate change made deadly fires in France twice as likely and those in Spain twenty times more likely. Smaller fires in the UK were not analysed by the study.
UN Climate Change leader Simon Stiell blamed fossil fuels for the fires, as well as storms in Chile and heatwaves in North America and Japan in recent weeks. “The climate alarm is blaring”, he said on Wednesday.
Guterres criticised new fossil fuel production projects and fossil fuel subsidies for causing hardship across the world. Discussing his speech, a senior UN official – who did not want to be named – said the subsidies amounted to trillions of US dollars a year and criticised pension funds and institutional investors, including insurance companies, for continuing to invest in fossil fuel projects.
Asked why world leaders and the public are not prioritising climate action, Guterres said they are distracted by wars in Ukraine, the Middle East, Sudan and elsewhere and sometimes forget “other aspects that are a sometimes even more dangerous threat”.
Also the fossil fuel industry and “some countries” are campaigning to pretend that climate change does not exist, he said, adding that the UN should be more active in “naming the situations as they are and the responsibilties as they are and mobilising the public opinion”.
After meetings in Paris and Madrid earlier in the week, the UK’s new foreign minister Ed Miliband issued joint statements with his French and Spanish counterparts – Jean-Noël Barrot and José Manuel Albares Bueno – calling on the world to reduce its dependence on fossil fuels.
They promised to do more to reduce emissions and protect their people and encouraged other governments to do the same.
The UK-French statement called on governments to publish UN climate plans, known as nationally determined contributions (NDCs), which are aligned with the Paris Agreement’s goal to limit global average temperatures to 1.5C above pre-industrial levels.
According to Climate Action Tracker, only three countries – the UK, Nigeria and Norway – have submitted NDCs with 2035 emissions reduction targets which are compatible with 1.5C. Fifty-two countries – including Egypt, Vietnam and Argentina – have yet to submit an NDC at all.
Defending science
Beyond action on emissions, the ministers also intervened in an ongoing dispute over the timing of the Intergovernmental Panel on Climate Change’s (IPCC)’s next flagship assessment.
Miliband and Barrot’s statement said they “underline the importance” of scientific report feeding into governments’ next global stocktake of progress on climate action in two years’ time, calling it a “critical input” to that process.
The timing of this report has been a contentious issue in government negotiations at the IPCC and at June’s climate talks in Bonn. While a group of nations calling themselves the “friends of science” want the report before the stocktake, others like Saudi Arabia and India have argued that this would make the report of a worse quality and less inclusive of developing countries’ scientists.
Science ‘under attack’ from fossil fuel interests at UN climate talks
The UK-Spanish statement weighed in less explicitly on this issue but said that they “recall the importance of scientific evidence and acknowledge the work of the IPCC in this respect.”
The British and French ministers said they would seek to accelerate reductions of emissions in methane, a particularly potent greenhouse gas, at COP31 in November. They encouraged governments “to work jointly to develop a marketplace for fossil fuels with near-zero methane intensity.”
Methane leaks from oil, gas and coal production are a major contributor to global warming. Over a 20-year period, methane traps around 80 times more heat than carbon dioxide.
The UK and Spanish statement emphasised the importance of supporting the Global South and underlined the need to mobilise sustainable financing “at scale with the challenge we face”. The previous UK government, in which Miliband was energy minister, cut climate finance to developing countries to pay for increases in military spending.
The UK government led by new Prime Minister Andy Burnham has yet to outline any major changes to climate finance in its two weeks in power but has announced it will convert some finance from grants to loans in order to free up money to subsidise bus travel in England.
More adaptation needed
Guterres said that “it is time to stop treating each disaster as an isolated tragedy and recognise the systemic risk that is unfolding before our eyes.” A recent study found that three-quarters of UK media reports about the British June heatwave did not mention climate change.
As well as reducing emissions, the UN Secretary-General called for measures to adapt vulnerable people to extreme heat. Specifically, he said that buildings should be built and retrofitted for extreme heat and that every city and country should have heat-health action plans and early warning systems. Over 250 cities have joined the UN’s ‘beat the heat’ initiative, he said.
The Portuguese diplomat called for governments and employers to do more to protect their workers from heat, criticising global fashion brands for not setting heat standards for the factories that supply them. “No one should have to risk their life to earn a living,” he said.
The post UN chief warns climate crisis “in overdrive” as El Niño threatens to fuel the fire appeared first on Climate Home News.
UN chief warns climate crisis “in overdrive” as El Niño threatens to fuel the fire
Climate Change
‘Ride the wave of momentum’: Australia announces once-in-a-decade Marine Parks Network review
In response to the federal government announcing its once-in-a-decade review of Australia’s Marine Parks Network, the following lines can be attributed to Elle Lawless, Senior Campaigner at Greenpeace Australia Pacific:
“Greenpeace Australia Pacific welcomes today’s announcement that the Albanese Government will review Australia’s Commonwealth Marine Parks Network. This is a rare, once-in-a-decade opportunity to strengthen our marine parks and ban industrial fishing in Australia’s marine protected areas.
“Australians would be appalled to know that more than half of Australia’s Marine Parks Network currently allows for extractive industries, like longlining, bottom trawling and oil and gas mining. These so-called ‘protected’ areas were designed to safeguard our beloved ocean wildlife and underwater ecosystems – that is what Australians expect. Damaging industrial industries should not be given a free pass to trawl, fish, drill or extract from our marine parks.”
“With the first Ocean COP just around the corner, and off the back of Australia’s move to ratify the Global Ocean Treaty earlier this year, the Australian government has a unique opportunity to ride the wave of this momentum and solidify itself as a true global ocean leader.
“Greenpeace Australia Pacific is calling for industrial activities to be banned from our protected waters and for at least 30% of Australia’s ocean to be protected as ocean sanctuaries. This review presents a rare opportunity to create more ocean sanctuaries, true blue havens where ocean life can recover, thrive and repopulate the surrounding waters.”
—ENDS—
‘Ride the wave of momentum’: Australia announces once-in-a-decade Marine Parks Network review
In recent days, prominent climate sceptics and rightwing commentators have shared charts on social media incorrectly implying that Europe is having its “quietest” year for wildfires in 2026.
These include Dr Matthew Wielicki, a former University of Alabama geochemist and self-described “professor in exile”, who was recently appointed by the Trump administration to lead the US Global Change Research Program.
However, these charts paint a misleading picture as they are skewed by encompassing the entirety of Russia in the data – including the vast plains of Siberia.
These charts also use data that include fires that are deliberately lit to manage cropland, which is a declining practice across much of Europe.
In this factcheck, Carbon Brief shows that the area burned by wildfires across the European Union in 2026 is second only to 2022 for this time of year.
The latest data from the European Forest Fire Information System (EFFIS) also shows that France has set a new modern record for area burned and Spain’s wildfire season is among the worst on record.
The fires have displaced more than a third of a million people across south-western Europe, while an impending heatwave has also raised fears of the fires worsening in the coming days.
‘Quietest year’
On 27 July, as wildfires raged across multiple European countries, former Conservative peer and climate-sceptic commentator Matt Ridley posted on Twitter that “2026 is the quietest year for wildfires in Europe by some distance”.
Ridley, who sits on the academic advisory council of the Global Warming Policy Foundation (GWPF), a UK-based climate-sceptic lobby group that refuses to reveal the sources of its funding, was responding to an article by Daily Telegraph columnist Tim Stanley.
Stanley’s column, headlined: “Climate change is real – and the right needs to get serious about it”, warned:
“This is no longer a matter of speculation: the wildfires of Europe, pitiless and persistent, are the way we live now.”
Ridley included a chart from Our World In Data, showing the cumulative area burned by wildfires by week for Europe. The chart puts 2026 as having the smallest area for this time of year in a dataset going back to 2012.
Ridley’s post was widely shared by prominent rightwing figures – including Richard Tice, deputy leader of the hard-right, climate-sceptic Reform UK party, former Conservative cabinet minister Jacob Rees-Mogg and multiple commentators.
Separately, Wielicki also shared a chart on Twitter to imply that wildfires in Europe are declining. Wielicki has previously claimed that the “science is not settled on climate change”.
The charts posted by Ridley and Wielicki both use data from the Global Wildfire Information System (GWIS). The GWIS category for “Europe” encompasses all the countries on the continent and includes the whole of Russia.
As a result, Russia accounts for about 74% of the area included in the GWIS definition of “Europe”.
Wildfires in Russia typically account for 80-90% of the burned area in the GWIS Europe dataset. In 2026, fires in Russia are substantially below average. Therefore, including Russia in this comparison creates the false impression that wildfire activity across Europe is unusually low.
Dr Calum Cunningham, a research fellow at the University of Tasmania’s Fire Centre, says that such claims are “highly misleading”, noting that “they rely on aggregating fire activity across an enormous and climatically diverse region”. He tells Carbon Brief:
“A relatively quiet season in Russia can easily mask an exceptionally active season in France or Spain. If the analysis is focused on the regions actually experiencing the current fires, the picture is very different.
“The reality is that western Europe has experienced an extraordinary sequence of climate conditions this year.”
In contrast, the EFFIS provides a subset of wildfire data specifically for the area covered by the 27 nations of the EU, which, therefore, excludes Russia.
Another difference between the two datasets is that GWIS monitors all fires – including those on agricultural land that are intentionally set alight. The burned area as measured by GWIS contains significant cropland area.
By contrast, EFFIS uses land-cover data and other information to filter specifically for forest fires.
Looking at the EU-only data from EFFIS reveals that Europe is far from having its “quietest” year. The bloc’s burned area, as of 29 July, is almost 435,000 hectares (ha) – second only to 2022 for this time of year.
Notably, Wielicki has actually continued to post charts based on GWIS data, even after acknowledging that “includ[ing] all of Russia, including vast areas of Siberia…isn’t a good proxy for Europe”.
French fires
Even looking at EU-wide data misses the scale of this year’s wildfires for some individual countries.
The chart below shows the surge in burned area in France since mid-July.
For much of the first half of the year, the country was having a wildfire season that was only slightly above average in terms of total burned area. However, a notable uptick began in the first week of July.
The third week of the month saw France break its previous cumulative annual record by more than 19,000ha. That gap has widened as the fires continue to burn; as of 29 July, the cumulative burned area in France during 2026 was nearly 24,700ha above the previous record.
The fires in France follow a record-breaking June heatwave that “dried out vegetation across the region, allowing fires to spread quickly”, wrote the New York Times.
On 27 July, French president Emmanuel Macron called a “crisis cabinet meeting” in order to address the fires “ravaging several areas of south-west France”, said France 24.
More than 220,000 people have been evacuated due to the Gironde fire, west of Bordeaux, in “what may be France’s largest peacetime evacuation”, reported the Associated Press.
In the Conversation, Cunningham and two other University of Tasmania researchers write that evacuation orders “protec[t] human lives, but makes it more likely houses and other structures will burn if there’s no one to defend them”. They add:
“There is little doubt climate change has made France and Spain’s wildfires worse. They represent yet another reason to redouble our efforts to tackle climate change and stabilise our climate.”
Central Spain scorched
While Spain’s fire season has not broken records in the same way that France’s has, it is on track to be among the worst since EFFIS began reporting data in 2006.
The chart below shows the rapid increase in burned area in Spain since 8 July. The latest data from EFFIS reveal that, as of 29 July, Spain has almost matched its previous record at this point in the year. It is also nearly five times the average area burned for this time of year.
In Spain, the wildfires have been concentrated in the central part of the country, near Madrid.
BBC News reported that the fires outside the capital have burned “an area more than twice as large as the city itself”.
Nearly 90,000 people were forced from their homes in central Spain by the fires, said the Associated Press.
Pedro Sánchez, Spain’s prime minister, called the fires a “painful expression” of climate change.
Meanwhile, the UK, French and Spanish governments have issued joint statements this week in response to the fires. The UK/Spain statement begins:
“This summer’s wildfires demonstrated that climate change was now a national security emergency facing Europe and threatening our way of life.”
Related
The post Factcheck: No, Europe is not having its ‘quietest’ year for wildfires appeared first on Carbon Brief.
Factcheck: No, Europe is not having its ‘quietest’ year for wildfires
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