Warming driven by deforestation caused an extra 28,000 heat-related deaths per year across Africa, South America and Asia over 2001-20, new research finds.
The study, published in Nature Climate Change, is the first to look at human health impacts of warming caused specifically by tropical deforestation, as opposed to the burning of fossil fuels, its lead author tells Carbon Brief.
The authors find that deforestation alone drove, on average, 0.45C of warming in the tropics over 2001-20, accounting for 64% of the total warming in regions with tropical forest loss.
They also find that tropical deforestation over 2001-20 exposed 345 million people to “local warming”, in addition to the warming they were already facing due to global warming.
Six out of every 100,000 people living in deforested areas died as a result of deforestation-induced warming during this time, they warn.
This number is higher in south-east Asia, with Vietnam setting a record of, on average, 29 deaths per 100,000 people.
A researcher who was not involved with the study tells Carbon Brief that the “sobering” paper “reframes tropical deforestation as not only a carbon emissions and ecological issue, but also a critical public health concern”.
Tropical deforestation
Tropical forests, mainly distributed across South America, Africa and Asia, account for 45% of global forest cover.
These regions are well-known for their high biodiversity and the crucial ecosystem services that they provide, such as carbon storage.
However, tropical forest loss is on the rise.
A record 6.7m hectares of previously intact tropical forest was lost last year, mainly due to fires and land clearing for agriculture. As the planet warms, worsening heat and drought extremes are also causing trees to become less resilient to change, resulting in forest degradation.
The new study uses data from the Global Land Analysis and Discovery laboratory at the University of Maryland to assess how tropical forest cover has changed year on year. The authors find that over 2001-20, a total of 1.6m square kilometres (160m hectares) of tropical forest was lost globally. This is shown on the map below, where blue indicates high forest loss and yellow indicates low loss.
The authors find the largest forest loss was in central and South America, but also highlight “extensive” loss in south-east Asia and tropical Africa.
Forest warming
Tropical deforestation has a wide range of negative consequences, including decreasing biodiversity, releasing carbon into the atmosphere and threatening the safety of Indigenous communities.
Loss of tree cover can also affect local temperatures by influencing the water cycle.
Water is constantly moving from the surface of the land into the atmosphere through a process called evapotranspiration. Plants play a crucial part in this process by moving water from the soil up through their roots and into their leaves, where it evaporates, cooling the air above. When trees are cut down, this cooling effect is reduced.
The authors use data of land surface temperatures from the NASA MODIS satellite to map warming in tropical regions over 2001-20. These results are shown in the map below, where red indicates warming and blue indicates cooling.
The authors find that between 2001-03 and 2018-20, surface temperatures increased by 0.34C in tropical central and South America, 0.1C in tropical Africa and 0.72C in south-east Asia. They add that “areas of forest loss coincide with areas of strong positive change in temperature across many regions of the tropics”.
By comparing their deforestation and surface warming maps, the authors find that deforested regions of the tropics saw an average of 0.7C warming over 2001-20, while areas that “maintained forest cover” saw an increase of only 0.2C.
By comparing the change in temperature in deforested regions with that in neighbouring locations without forest loss, they find that deforestation alone caused 0.45C of warming in the tropics over 2001-20 – accounting for 64% of total warming experienced over those regions.
Heat exposure
High temperatures can be deadly.
During periods of extreme heat, people can suffer from heat stroke and exhaustion – and even die. Those with underlying health conditions are at higher risk of fatal complications.
The authors use data from Oak Ridge National Laboratory’s LandScan to map where people live in the tropics. They estimate that 425 million people live in regions that were exposed to tropical deforestation over 2001-20, and just over three-quarters of them were exposed to warming as a result of the loss of forest cover.
Finally, the authors estimated “heat-related excess mortality” due to nearby tropical deforestation.
Using data from the 2019 Global Burden of Disease study, they determine the number of “non-accidental” deaths in each deforested tropical area. This excludes deaths from “external” causes, such as accidents and suicides, but includes “internal” causes, such as disease.
The researchers then used previously published “temperature-mortality” relationships for different countries. These relationships show the link between temperature and excess mortality rate, indicating the percentage increase in mortality for every degree of warming.
These relationships vary between countries, as people in hotter regions are generally better adapted to extreme heat.
By combining the data on local warming due to deforestation, temperature-mortality relationships and the non-accidental mortality data, the authors calculated how many non-accidental deaths would have been expected in deforested regions if they had not warmed due to the loss of forest cover.
By comparing the real and counterfactual mortality rates, the authors were able to calculate the total mortality burden due to tropical deforestation-induced warming.
Overall, the authors find that tropical deforestation drove an additional 28,300 deaths every year over 2001-20, accounting for 39% of the total heat-related mortality from global climate change and deforestation combined over locations of forest loss.
The study finds that, on average, six out of every 100,000 people living in deforested areas died as a result of deforestation-induced warming. However, these numbers vary by country.
The chart below shows the average annual deaths due to deforestation-induced heat per 100,000 people living in areas of forest loss.
Dr Carly Reddington is a research fellow at the University of Leeds and lead author of the study. She tells Carbon Brief that it is the “first study to look at human health impacts of tropical deforestation-induced warming”.
Dr Nicholas Wolff, a climate change scientist at the Nature Conservancy who was not involved with the study, tells Carbon Brief that the paper is “sobering”. He adds that it “reframes tropical deforestation as not only a carbon emissions and ecological issue, but also a critical public health concern”.
Data-scarce
The authors note that there are no country-specific heat vulnerability indices available for African countries. To develop their data for African countries, they used the average heat vulnerability index for South America.
Reddington tells Carbon Brief that Africa is the most “uncertain region” in the study and tells Carbon Brief that “more data is really crucial” to develop more accurate estimates.
Wolff tells Carbon Brief that extrapolating heat-mortality relationships “from data-rich regions to data-poor ones” is a “common practice in global-scale climate-health research”.
He praises the overall methodology as “innovative, transparent and scientifically sound, with appropriate caveats”.
Dr Luke Parsons, a climate modelling scientist at the Nature Conservancy, tells Carbon Brief that the conclusions are “robust”. However, he notes some “methodological issues” with the paper, such as the fact that all results are modelled, rather than measured.
He tells Carbon Brief that future work could assess “near-surface air temperature and humidity changes associated with deforestation, as well as study regional air temperature changes beyond deforested areas”.
While the new study focuses on warming within one square kilometre of forest loss, Reddington tells Carbon Brief that “deforestation is associated with warming up to 100km away”.
Furthermore, the study notes that the increase in deaths due to excess heat is likely to affect the most vulnerable members of society the most. It says:
“Vulnerable populations, particularly traditional and Indigenous communities, often live near deforested areas and face limited access to resources and infrastructure needed to cope with the combination of rising temperatures and environmental changes caused by deforestation and climate change.”
Wolff also stresses this disparity, adding that “many of these communities depend on forest clearing for agriculture, income and survival, and are forced to make difficult choices between short-term economic needs and long-term health and environmental stability”.
The authors also note that deforestation can drive a range of other interacting health problems, which were not considered in this study. For example, deforestation is linked to a rise in zoonotic diseases, such as malaria.
Dr Vikki Thompson, a climate scientist at the Royal Netherlands Meteorological Institute who was not involved in the study, says that the findings of the paper are “relevant to everyone”. She continues:
“We can reduce impacts of extreme heat by planting more trees and reducing deforestation everywhere, on both local and international scales.”
The post Warming due to tropical deforestation linked to 28,000 ‘excess’ deaths per year appeared first on Carbon Brief.
Warming due to tropical deforestation linked to 28,000 ‘excess’ deaths per year
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
-
Climate Change12 months ago
Guest post: Why China is still building new coal – and when it might stop
-
Greenhouse Gases12 months ago
Guest post: Why China is still building new coal – and when it might stop
-
Greenhouse Gases2 years ago嘉宾来稿：满足中国增长的用电需求 光伏加储能“比新建煤电更实惠”
-
Climate Change2 years ago嘉宾来稿：满足中国增长的用电需求 光伏加储能“比新建煤电更实惠”
-
Climate Change2 years ago
Bill Discounting Climate Change in Florida’s Energy Policy Awaits DeSantis’ Approval
-
Renewable Energy9 months agoSending Progressive Philanthropist George Soros to Prison?
-
Carbon Footprint2 years agoUS SEC’s Climate Disclosure Rules Spur Renewed Interest in Carbon Credits
-
Greenhouse Gases1 year ago
嘉宾来稿：探究火山喷发如何影响气候预测