Anne Jellema is executive director of 350.org and David Hillman is director of Stamp Out Poverty.

This coming week, as record-breaking heat has morphed into killer wildfires, major oil and gas companies will report their second-quarter earnings and are widely expected to announce profits that have doubled or even quadrupled in the last three months. The obscenity of that contradiction is impossible to ignore.

Oxfam analysis, released as the Q2 earnings season gets underway, shows that the world’s six largest fossil fuel corporations – BP, Chevron, Eni, ExxonMobil, Shell and TotalEnergies – are on course to nearly double their combined net income compared with the first quarter of the year, from $23 billion to around $45 billion.

Their projected full-year profits of $147 billion would exceed everything the six firms made combined over the previous 21 months. Chevron’s profits alone are expected to have quadrupled to $1,200 a second over the last three months; ExxonMobil’s have roughly tripled to $1,800 a second. The juxtaposition of profit on that scale, arriving in the same weeks that communities are counting the cost of deadly heatwaves, forest fires and high energy bills, is increasingly difficult to ignore.

Covering the cost of climate damage

Not long ago, the idea that fossil fuel companies should contribute directly towards the cost of climate damage was dismissed as activist rhetoric. Today it is reflected in legislation, litigation and mainstream policy debate.

Several US states have passed “Climate Superfund” laws requiring major fossil fuel companies to help fund climate adaptation and disaster recovery. Courts are hearing cases seeking compensation for climate harms, while governments across Europe continue to debate the future of windfall taxes on outsized energy profits.

Comment: Major emitting countries knew of climate risks decades earlier than claimed

These developments may appear disconnected, but they reflect a broader shift in public thinking: if societies are paying an ever higher price as our climate warms, should the excessively profitable fossil fuel companies whose products have substantially caused those costs not bear more of the burden of paying for them?

Europe’s heatwaves fuelled by emissions

The events of this summer have only sharpened that question. Europe has experienced repeated heatwaves, with temperatures exceeding 40°C across parts of Spain, Portugal, France and Germany. England recorded its hottest June on record, while wildfires have affected communities across southern Europe and, increasingly, parts of the UK.

According to researchers at the London School of Hygiene & Tropical Medicine and Imperial College London, more than 2,300 heat-related deaths occurred across twelve European cities during one recent ten-day heatwave alone, with climate change estimated to have roughly tripled the number of deaths.

Separate Oxfam analysis of academic data published in Nature goes further, finding that the emissions of just five of these corporations – BP, Chevron, ExxonMobil, Shell and TotalEnergies – were sufficient to cause around one in four of the heatwaves reported globally between 2000 and 2023: heatwaves that would have been virtually impossible without human-made climate change.

WHO issues new guidance on heat-health action plans, as El Niño sets in

Nor is Europe unique. There is looming famine in Uganda and India endured prolonged pre-monsoon temperatures above 48°C earlier this year. North America has faced successive heat domes, while smoke from hundreds of Canadian wildfires has periodically produced some of the world’s worst urban air quality, affecting millions of people across Canada and the United States.

Scientists have become increasingly confident in attributing many of these extremes to human-caused climate change. Rapid attribution studies, pioneered over the past decade, now routinely assess how much more likely or more intense individual weather events have become because of greenhouse gas emissions.

‘Polluter pays’ principle in law

Against this backdrop, the “polluter pays” principle is a basic standard of responsible behaviour: if you cause damage, it is on you to pay for it. It is a longstanding concept in environmental law and economics that those responsible for creating pollution should bear a proportionate share of the costs it imposes on society.

In 2025 a survey found that 81% of people supported increased fossil fuel taxes being directed to help communities most impacted by extreme weather. And it is no longer just a hypothetical prospect.

A mandatory surtax on highly polluting industries is gaining support as part of the UN Convention on International Tax Cooperation, alongside robust measures to prevent jurisdiction-shopping and anchor taxing rights in real economic activity. Governments meeting in New York next month to negotiate the framework convention should seize the moment to get behind both.

The stakes are high because the economics of the energy transition are increasingly clear. Renewable electricity is now among the cheapest forms of new power generation in much of the world. Yet many countries with abundant renewable resources continue to face prohibitively expensive borrowing costs, limiting their ability to invest at the speed required. Meanwhile, massive fossil fuel profits remain only lightly taxed or entirely avoided in many jurisdictions.

Analysis by the Global Alliance for Tax Justice and partners estimated that a 20% surtax on the profits of the world’s 100 largest oil and gas companies could have generated more than US$1 trillion since the Paris Agreement was signed in 2015.

Time to design mechanisms for justice

Whether governments choose that particular mechanism is ultimately a political decision. But the analysis illustrates a broader point: claims that public investment in climate resilience or clean energy is unaffordable sit uneasily alongside the scale of profits regularly generated by the fossil fuel industry, profits that, this quarter, are on course to nearly double in three months.

There are legitimate debates about the design of windfall taxes, competitiveness, investment incentives and international coordination. But the wider principle – that those who have benefited most from fossil fuel extraction should pay more towards managing its consequences – is no longer confined to campaign groups.

Extreme heat costing India’s poorest workers 2% of GDP, survey finds

It is increasingly part of mainstream discussions among policymakers, economists and legal scholars and, if well designed, such mechanisms will incentivise investment where it’s needed and strengthen international coordination.

This summer has made that conversation harder to avoid. The question is no longer whether fossil fuel giants should pay for the enormous economic and human costs being suffered by communities every day due to our rapidly warming climate. It is when will governments step up and make them pay, for the damage already done and to build the resilience we need going forward?

The post The case for making polluters pay has moved into the mainstream appeared first on Climate Home News.

The case for making polluters pay has moved into the mainstream

The global goal to halt and reverse nature loss by 2030 “will not be achieved” unless action by countries “accelerates rapidly”, says a draft UN report.

Countries are falling short on 22 of the 23 targets for 2030 they set under the Kunming-Montreal Global Biodiversity Framework (GBF), the “Paris Agreement for nature”.

That is according to a draft version of a global report prepared by the UN Convention on Biological Diversity (CBD), published on 26 July.

The report will be finalised ahead of the next nature summit, COP17, taking place in Armenia in October of this year.

The second draft of the global report has undergone “peer review”, but will still be subject to “technical edits” before being formally published ahead of COP17.

The final version will inform a global review of countries’ progress towards meeting the world’s 2030 nature goals, which will take place in Armenia.

Below, Carbon Brief explains why the report has been produced and what it says about countries’ progress in areas such as restoring ecosystems and raising funds for biodiversity.

Global report

In Montreal, Canada, in 2022, nearly every country in the world agreed to the GBF. The overall “mission” of the framework is to halt and reverse biodiversity loss by 2030. Its “vision” is to bring the world into “harmony with nature” by 2050.

The GBF includes a list of 23 targets for 2030. They cover an expansive range of topics, from restoring ecosystems, to addressing pollution and providing developing nations with finance to help cover the costs of protecting nature.

As part of the GBF and its underlying documents, countries agreed to a schedule for monitoring their progress towards achieving the 2030 targets.

This included the preparation of a “global report” of progress coordinated by the CBD, which will inform a “global review” undertaken by countries at COP17.

The global report draws on countries’ national reports, which were due to be submitted to the UN in February of this year. It also draws on countries’ national nature plans, known as “national biodiversity strategies and action plans” (NBSAPS) and national targets, which were both due in 2024.

Not all countries have met the call to publish these documents and targets. According to the UN, 45% of countries published NBSAPs in time to be considered for the report, 83% had submitted at least one national target and 66% had produced their new national report.

The first draft of the global report was published on 29 June 2026. This draft was subject to a “peer review process”, which invited countries and observers, such as NGOs and businesses, to submit comments on all aspects of the report.

The second draft, which has been revised based on the peer review, was published on Sunday 26 July. (This was just ahead of COP17 preparatory talks being held in Nairobi from 27 July to 1 August.)

A final version of the global report will be formally published ahead of COP17, which will take place from 19-30 October.

Overall findings

The second draft of the global report says that the GBF has led to “unprecedented” interest in tackling biodiversity loss, but adds:

“However, unless collective implementation accelerates rapidly, the 2030 targets and mission will not be achieved.”

It says that countries have taken some action to address all 23 targets, but that “no target presents a fully positive picture”.

(The first draft has slightly softer language. It “concludes that the world is not yet on track to collectively meet the global ambitions that the parties to the convention set when they adopted the framework”.)

The report identifies “two distinct gaps in progress”, relating to ambition and implementation.

First, that the national targets and plans submitted by countries “do not yet fully reflect the scope and level of ambition” of the global targets in the GBF.

Second, countries are not taking sufficient action to achieve their targets, according to the report.

It adds that progress is “particularly lagging” for addressing the “indirect drivers of biodiversity loss”, such as harmful business practices and government subsidies promoting them.

In addition, countries are showing “consistent gaps” in making progress on taking action to protect “marine, coastal and inland water ecosystems”.

The report produces a “scorecard” assessing countries’ progress towards meeting each of the 23 targets of the GBF.

The scorecard includes an “overall score” of between 0 and 1 for each target. This is calculated by considering countries’ self-reported progress in their plans and targets, as well as an assessment of progress based on a set of agreed indicators.

The results are split into four categories: 0-0.25 is red, 0.25-0.5 is orange, 0.5-0.75 is yellow and 0.75-1 is green.

The report gives a “green” score for just one target, indicating overall positive progress. This is target 8, on “minimising” the impact of climate change on biodiversity, including through mitigation and adaptation.

Elsewhere, the draft says that countries have “reported gaps in the scale and timely provision” of “financial resources, capacity-building and development, technical and scientific cooperation, access to and transfer of technology, and knowledge sharing”. It adds:

“These barriers can result in uneven capacities and cause specific technical and financial constraints for all parties, but particularly for developing-country parties. It is likely these constraints are even more pressing for least developed countries and small island developing states.”

Protecting and restoring nature

Target 3 of the GBF is for countries to protect “30% of Earth’s land and sea for nature” by the end of the decade.

This commitment – referred to as “30 by 30” – is widely considered the flagship target of the agreement.

The report says that countries are making “progress in expanding and managing protected areas, especially for marine and coastal areas”. But it adds that “current ambition and implementation remain insufficient to fully achieve all aspects of the target”.

It continues that, according to countries’ available national targets, “monitoring and reporting of some elements of the target remains low”. This includes “those relating to equitable governance of protected areas” and “recognition of Indigenous and local territories”.

The report adds that countries “face significant challenges in implementation, particularly related to lack of finance and capacity”.

(An investigation by Carbon Brief and the Guardian in 2025 revealed that more than half of nations that have submitted UN biodiversity plans do not commit to “30 by 30” within their borders.)

Another conservation measure included in the GBF is target 2, which aims to ensure that at least 30% of land and sea areas are under restoration by 2030.

The report says that “restoration efforts are expanding”. However, it says that “current commitments to restore areas and implementation of those commitments remain below the level required” to achieve target 2.

It adds that countries’ national targets are “generally well aligned with target 2”, but that “addressing the effectiveness of restoration efforts is often absent”.

Moreover, the report adds that monitoring of progress is “constrained by inconsistent definitions and monitoring approaches for ecosystem degradation and restoration”.

Another “major barrier” is a lack of available finance for developing countries looking to restore ecosystems, it says.

Climate and biodiversity links

Target 8 of the GBF is the only one to specifically address climate change, one of the major drivers of biodiversity loss.

It says countries should “minimise the impact of climate change” on biodiversity through mitigation and adaptation, including “nature-based solutions” and “ecosystem-based approaches”.

Target 8 was the only one to achieve a “green” marking in the report’s scorecard of progress (see: Overall findings).

The report says that actions to make biodiversity more resilient against climate change are “progressing”. Yet “implementation remains constrained by data gaps, limited means of implementation and the need for stronger coherence between biodiversity, climate and disaster risk reduction planning”.

It continues that countries’ national targets “generally” show “good alignment” with target 8, across “all elements apart from efforts to minimise the impacts of ocean acidification”.

It adds that the deployment of nature-based solutions and ecosystem restoration is not yet at a “sufficient scale”.

Subsidies

Overall progress is “insufficient” on target 18, which calls on countries to identify subsidies and other incentives that are harmful for biodiversity by 2025, says the GBF report.

It also outlines that nations should “eliminate, phase out or reform” these subsidies in a “proportionate” way, reducing them by at least $500bn per year by 2030.

Countries should first target the “most harmful” incentives, while simultaneously scaling up positive incentives for nature, it adds.

The report finds that countries have made some progress in assessing, compiling inventories and commissioning studies on harmful subsidies.

But issues remain, such as incomplete data and the lack of agreed definitions on which subsidies are deemed “harmful”.

Several national reports also note “entrenched interests and political barriers to subsidy reform”, says the report.

Only one-quarter of countries’ national targets that are “highly aligned” with target 18 are “on track” to be met, it finds. Most show “insufficient progress”.

It notes that 38% of countries have addressed the 2025 aim to identify harmful subsidies in their national targets “to some extent”.

Countries’ national reports do not “provide a sufficient basis to determine” whether this goal was met, says the report, but available evidence “suggests” that it was not.

Recent analysis by Carbon Brief found that just 16% of the 134 national reports submitted so far appear to meet the aim.

The report outlines that half of countries have set national targets addressing plans to eliminate, phase out or reform harmful incentives. Almost 60% mention scaling up positive incentives, it adds.

Just 27%, however, address the issue of reducing subsidies by at least $500bn annually by 2030. Also, only 5% set quantitative national targets to reduce subsidies.

There are two headline “indicators” to measure progress on target 18. The first shows that 30% of countries have outlined information on their nature-positive incentives.

The second indicator shows that 22 countries submitted the value of their biodiversity-harmful subsidies, which amounted to a total of $268bn spent on harmful subsidies over 2022 to 2025 – averaging $67bn each year.

Carbon Brief’s analysis had identified an estimated $270bn each year, based on a wider list of submissions from 32 countries. (More countries submitted national reports since the CBD’s deadline to be included in the global report in February.)

All of these figures remain well below the estimated trillions of US dollars spent annually.

The report notes that different methodologies could lead to global subsidy estimate “inconsistencies”, meaning that reported values are likely “underestimates”.

The amount of positive incentives in place is also likely underestimated, it adds.

The report says that harmful subsidies may have declined by around 20% in recent years, based on figures consistently reported by a minority of countries over 2022-24.

Despite this, the total value of subsidies “remains higher than the resources that parties reported mobilising for biodiversity”. (See: Mobilising finance.) 

Mobilising finance

Overall progress on raising biodiversity finance has been “insufficient”, according to the report.

Goal D of the GBF, shown below, states that countries must close a $700bn biodiversity gap by 2030 through ending harmful subsidies ($500bn per year) and mobilising resources from the global north to south ($200bn per year).

This target aims to raise “at least $200bn per year” by 2030 from “all sources”, including domestic, international, public and private funding.

In all, countries reported raising a cumulative total of $186.4bn over four years, according to the report.

While it adds that it “is still too early to conclude”, the report states that the total finance mobilised so far “falls far short” of what is needed to close the biodiversity finance gap.

Target 19, shown below, states that developed countries and others should boost finance for nature to “at least $20bn” per year by 2025 and “at least $30bn” by 2030. This falls to developed countries and others that “voluntarily assume” the obligation of contributing.

However, the report suggests that the milestone of raising “at least $20bn per year by 2025” was “likely not achieved”.

Between 2020 and 2023, reporting countries cumulatively raised just $17.7bn in international public funding for biodiversity, according to the report.

This amounts to an average of $4.4bn per year between 2020-23, with the total touching its highest at $5.2bn in 2023.

The report cautions that this figure “should be read as a minimum”, as it does not account for all potential flows of biodiversity finance.

Both estimates “fall below the $20bn milestone”, although the report adds that a “definitive assessment will only be possible” once data for 2024 and 2025 are included.

An earlier draft of the report included language noting that biodiversity-related “official development assistance” remains “well below the agreed 2025 milestone”. This was cut from the summary in this latest iteration of the report.

References to the OECD reporting a “shortfall in funding” and projecting “a decrease for 2024 and 2025” – suggesting the $20bn target was “unlikely to be met” – were also removed from the latest draft.

The chart below shows how international public funding for biodiversity has varied from 2020 to 2023, according to the report.

By comparison, domestic spending makes the largest cumulative contribution to biodiversity finance, at ($135.9bn) over the four years. However, spending has “declined” as a share of GDP. It also notes that spending varies “greatly”, from 0.1% to 2.7% of GDP.

According to the report, many countries highlighted that national budget allocations for biodiversity are “far too low” and that biodiversity “frequently loses out to competing development priorities”, including “defence, food security and infrastructure”.

At COP15 in Montreal, the EU and several other countries pushed for the inclusion of “all sources” of finance in the final text – including private finance and “innovative” schemes.

Private and “innovative” biodiversity finance – which spans a plethora of sources such biodiversity offsets and debt-for-nature swaps – was eventually included in target 19.

The report, however, notes that private finance “peaked in 2021 and fell afterwards” and “remains particularly undeveloped”, with a cumulative total of $32.7bn between 2020-23.

At the same time, the report notes that only 26% of all countries had reported data on private biodiversity finance, making it harder to assess funding declines in 2022 and 2023.

Genetic resources

The report finds there has been limited progress on sharing genetic biodiversity data.

”Digital sequence information” (DSI) refers to genetic data derived from biodiversity, which is often sourced from species in biodiversity-rich developing countries.

These countries have long called for an international mechanism to ensure that the benefits of DSI are shared fairly with the people living where the resources were “discovered”, including Indigenous communities.

At COP16, countries agreed to the first-ever global fund, called the Cali Fund, for companies profiting from genetic data to contribute to conservation goals on a voluntary basis.

However, experts have cautioned that much rests on whether countries develop strong national laws to support the COP16 agreement. This could include incentivising companies in their regions to contribute to the fund.

In the GBF, target 13 and goal C address elements of DSI, including the sharing of benefits from genetic resources and their digital derivatives.

According to the report, 79% of countries submitted national targets that address legal, policy and administrative measures to enable benefit-sharing from DSI. Some 71% included measures to facilitate access to genetic resources.

The report finds that the “strongest progress” has been in developing laws and policies, which are now at an intermediate stage.

The “most fundamental regulatory barrier”, according to many countries cited, is the lack of a “dedicated” national framework to enable access to genetic resources and share benefits with communities.

This would involve enacting laws compatible with the GBF, setting up digital registries to catalogue and trace genetic resources, as well as implementing tracking systems to monitor how they are used. It would also include a financial mechanism to pay communities for the use of their traditional knowledge.

Progress in monitoring monetary and non-monetary benefits from DSI is “much weaker” and is “particularly limited” for measures related to the Cali fund.

According to the report, most parties have “no monitoring systems [for evaluating benefits from genetic resources] in place, or [are] still developing them”. It says they add that the benefits from genetic resources are hard to track “across borders and along value chains through to the final product”.

For those that have tracked benefits, it says that countries reported a cumulative $6.9m in receipts from the use of genetic resources between 2022 and 2025. It adds that “several parties reported that they had received no monetary benefits” to date.

Countries also reported more than 960 non-monetary benefits, ranging from technical training to research participation. The report cautions that these “fluctuated over time rather than increasing consistently, and cannot be seen as indicative of global benefit-sharing”.

In December 2025, Carbon Brief reported that the Cali fund had received only one contribution of $1,000 as an “icebreaker”. No other major companies have stepped up to fill the fund.

Meanwhile, the report states that the formal protection of traditional knowledge held by Indigenous peoples and local communities remained “underdeveloped”.

It says that a “significant number” of countries raised concerns about gaps in recognition of Indigenous peoples’ rights and dedicated registries to document their traditional knowledge.

The report says it is not yet possible to assess progress towards goal C:

“To date it is not possible to comment on whether benefits are being shared fairly and equitably nor on the role played by traditional knowledge and Indigenous peoples and local communities. Therefore, progress towards goal C cannot yet be assessed.”

Pollution

Target 7 of the GBF focuses on tackling pollution from pesticides, chemicals, plastic and other sources.

It calls for countries to reduce pollution risks and negative impacts “from all sources” to “levels that are not harmful” to biodiversity and ecosystems by 2030.

It also aims to reduce excess nutrients in the environment and overall risks from pesticides and hazardous chemicals by “at least half”.

The draft report finds that there is no significant change or insufficient progress on 60% of national targets categorised as being highly aligned with target 7. Only one-third of these national targets (35%) are on track to be achieved by 2030.

On average, it says countries have addressed around half of the various elements of target 7 “to some extent” in their national targets.

The most frequently-mentioned aspect of the target – addressed by 72% of countries – refers to reducing pollution from all sources by 2030.

One headline indicator related to target 7 focuses on the concentration of pesticides in the environment.

Just five countries out of 125 submitted estimates on this, according to the report. It says only one country has met the aim of halving the overall risk from pesticides on a national basis so far.

Measures to address plastic pollution are the most frequently reported actions by countries in relation to this target, including bans on single-use bags and straws.

A number of countries in Europe and Asia have also implemented measures to reduce nutrient losses from fertilisers and slurry.

A “major challenge” for countries in advancing pollution aims is “effectively and fairly considering and managing impacts on food security and livelihoods”, according to the report.

Several countries point to a lack of national funding to implement measures towards achieving this target.

Some developing countries also list poor wastewater-treatment infrastructure as a “persistent challenge” on this issue.

Invasive species

Invasive alien species refers to those that have moved to and become established in a region outside their natural habitat, as a result of human activities. This has negative impacts for local biodiversity and ecosystems.

Target 6 of the GBF calls for countries to, among other things, reduce the rates of introduction and establishment of invasive alien species by 50% by 2030.

The draft report says countries are “taking action” on this target, but progress is “difficult to assess”.

Two-thirds of national targets aligned with target 6 show “no significant progress or insufficient progress”, it finds. Fewer than one-third are on track to be achieved by 2030 and just 1% of these national targets have already been achieved.

But most countries have made progress in putting in place measures to manage invasive species – mostly focusing on reducing the introduction rate and impact of species.

Countries have addressed around half of the different elements of the invasive species target “to some extent” in their national targets, finds the report.

But fewer than one-third (30%) have set national targets that put a numeric goal on reducing invasive species.

Island biosecurity programmes and measures to intercept invasive species at country borders are among the actions countries have put in place to tackle the issue.

The report lists some barriers countries say stand in the way of achieving the target. These include a lack of baseline data from which to measure a 50% reduction rate, poor early-detection systems and a lack of funding for long-term reduction efforts.

Some countries also cite capacity and technical challenges in monitoring invasive species, according to the report.

They say many of these species “go unnoticed for years before impacts become apparent”, it adds, with countries arguing that setting a specific reduction target is “challenging”.

Related

Analysis: 84% of nations miss deadline to identify ‘nature-harming’ subsidies by 2025 

28.07.2026

International policy

UK withdraws millions in funding from world’s second-largest rainforest in Congo 

15.07.2026

Nature

Livestock heat deaths in transit doubled in UK record-hot summer of 2025

25.06.2026

Food and farming

Mombasa: Key outcomes from the Our Ocean Conference in Kenya

24.06.2026

Marine life

The post World falling short on 22 of 23 nature targets for 2030, says draft UN report appeared first on Carbon Brief.

World falling short on 22 of 23 nature targets for 2030, says draft UN report

Rising temperatures are redistributing the risk of childhood malaria in sub-Saharan Africa, resulting in areas of “new risk” in the east and south of the continent, but also “relief hotspots” in western Africa.

This is according to a new study, published in Nature, which provides the “most comprehensive look to date at the impact of climate change on any infectious disease”.

The research finds that since the year 1900, climate change has resulted in one extra case of malaria for every 1,000 children in sub-Saharan Africa on average.

Over the 21st century, climate change is expected to drive down malaria rates across the continent on average, as temperatures rise above the optimum range for mosquitoes.

However, the authors emphasise that continent-wide averages hide more detailed local trends.

They find that cooler parts of Africa face an increase in malaria risk, as rising temperatures have made the regions more suitable for malaria-carrying mosquitoes, while warmer regions see a suppression in malaria cases.

The lead author tells Carbon Brief that this is the first study to use “attribution” – a field of climate science which uses models to compare conditions in a world with global warming to one without – to assess the impact of climate change on malaria.

The study also reveals that climate change is not the main driver of shifting malaria risk in Africa, with public health measures and government policy making a more significant impact.

The “most important” message from the study, according to another expert, is that to eliminate malaria entirely, “effective surveillance, prevention and treatment remain substantially more influential – and more actionable – than climate change alone”.

Childhood malaria

Malaria kills hundreds of thousands of people every year. The World Health Organization (WHO) estimates that 610,000 people died due to the disease in 2024.

The disease is transmitted to humans by bites from mosquitoes infected with the malaria parasite. Malaria spreads most rapidly in warm, wet regions, where the parasite-carrying mosquitoes can live and breed.

However, malaria is preventable. A total of 42 countries – mainly in Europe and the Americas – have eliminated the disease entirely through a combination of measures including insecticide use, draining the swamplands that provide breeding habitats for mosquitoes and improving basic healthcare services .Global mortality from malaria declined by 90% over the 20th century.

Today, the vast majority of malaria cases are recorded in Africa, which was home to 95% of malaria cases and deaths in 2024. Children under the age of five make up three-quarters of all African malaria deaths.

The malaria-causing parasite can be detected using a blood test. Over the last century, scientists, government officials and healthcare professionals have collected thousands of blood samples from people across sub-Saharan Africa and tested for the presence of the malaria parasite.

In 2017, scientists brought together more than 50,000 samples collected from sub-Saharan Africa over 1900-2016. This data provides a “snapshot” of the amount of malaria in the population in any year in the last century the study explains.

Dr Colin Carlson is an assistant professor of epidemiology at the Yale school of public health and lead author of the study. He tells Carbon Brief that malaria in Africa is “extraordinarily well documented”, as a result of academic interest and colonial rule in the continent.

The size and quality of the malaria dataset are “exceptionally rare”, Carlson says. He explains that the dataset stretches back to before the impacts of human-caused climate change were strongly felt, making it “extraordinarily” valuable for this analysis.

The chart below shows the percentage of children between two and 10 years old who tested positive for the malaria parasite over 1900-2016. Each dot indicates one blood test result and the pink vertical bars indicate periods of “successful malaria prevention intervention”, such as the 1955-69 global malaria eradication programme.

Attribution

The authors use the blood test survey data to develop a statistical model separating out the climatic, social and economic factors that affect malaria, such as temperature, rainfall, economic development, healthcare and population changes. This allows the authors to isolate the effects of the climate on malaria.

They find that malaria prevalence in children peaks when average monthly temperatures reach 24.9C, dropping off in warmer and cooler climates.

Mosquitoes also need stagnant or slow-moving water in which to lay their eggs. The authors find that periods of drought tend to decrease malaria prevalence one-to-two months later, whereas floods increase prevalence two-to-three months later. However, they conclude that rainfall is “less important than temperature” in predicting malaria rates.

They then combine the statistical models with climate models, to simulate childhood malaria rates in a range of past and future climates.

First, the authors simulate malaria rates in the present day, by running the models using the climate of 2000-14. They then carry out the same analysis, using the climate of a hypothetical world without human-caused climate change.

By comparing the two, the authors were able to attribute the impact of climate change on malaria rates across Africa.

The link between climate change and malaria in Africa is complex and “surprisingly contentious”, according to the authors. For example, they write that “malaria resurgence in the east African highlands became a particular point of contention, with over a dozen studies arguing for or against climate change as a substantial driver”.

It adds:

“Today, malaria experts generally agree that climate change has contributed to elevational shifts in malaria epidemics and the geographical ranges of mosquito vectors. However, the cumulative effect of climate change on the burden of malaria is still an open question.”

Lead author Carlson says this paper is “one of the first impact attributions on infectious disease” and the first attribution study on climate change and malaria. He adds:

“I think it’s the most clarity we’ve had on the malaria question.”

Dr Teresa Yamana, an associate research scientist at Columbia University, who was not involved in the study, praises its “rigorous” methodology. She tells Carbon Brief that the work “demonstrates the potential of climate attribution methods to quantify the impacts of climate change on infectious diseases”.

Warming world

The findings show that “climate change isn’t just making malaria worse or better – it’s moving it, says study author Prof Tamma Carleton, an assistant professor at UC Berkeley:

“Whether a place sees elevated malaria risks or reduced burdens under climate change depends on how hot it is today. We see relief in the hotspots and new risk nearly everywhere else.”

For example, in the Ethiopian highlands, low temperatures – which are unsuitable for mosquitoes to live and breed – have historically limited the spread of malaria. However, the region has seen childhood malaria rates increase by more than eight cases per 1,000 children since the year 1900 as rising temperatures have allowed the insects to expand their habitat.

The authors also found a similar increase in malaria prevalence in cooler southern African countries.

In contrast, global warming is pushing average temperatures above the ideal range for mosquitoes in many hotter parts of Africa, driving down malaria rates. The authors find that in western Africa, climate change has caused a reduction of four malaria cases per 1,000 children per year by 2014, reducing prevalence by 1-2%.

Overall, climate change has resulted in one extra case of malaria for every 1,000 children in sub-Saharan Africa since the year 1900, the study says.

The authors also run their models for three future climate scenarios: low (SSP1-2.6), intermediate (SSP2-4.5) and very-high (SSP5-8.5) emissions pathways. Comparing these to the present-day model results shows how climate change could affect malaria cases over the coming century.

They find that the trends observed so far will largely continue into the future – meaning climate change will lower the prevalence of malaria in warm regions and increase the prevalence in cool regions.

Email

This field is for validation purposes and should be left unchanged.

Free fortnightly newsletter

Email

The study concludes that under the intermediate scenario, which is broadly in line with current climate policies, warming will drive down childhood malaria cases by about three cases per 1,000 children in central Africa and 16 cases per 1,000 children in west Africa by the end of the century.

By contrast, cases could increase by around 20% over the same period in regions such as the Rift Valley and coastal southern Africa – a rise of 30 cases per 1,000 children.

The maps below show changes in childhood malaria prevalence due to climate change in today’s climate (left) and the climate of 2096-2100 under the intermediate scenario (right).

Red indicates an increase in malaria prevalence and blue indicates a decrease. Greyer colours indicate greater uncertainty in the model results. White indicates regions where no data was collected.

Carlson tells Carbon Brief that this is “the first study to really confidently answer the highland East Africa debate”.

Eradicating malaria

Healthcare workers, governments and scientists have been working to eliminate malaria for decades.

On average, the authors find that climate change will reduce the prevalence of malaria in sub-Saharan Africa, as temperatures rise above the optimum range for mosquitoes. This effect is more pronounced at higher warming levels.

Under the low emissions scenario, about 1 case per 1,000 children will be averted by the end of the century. Meanwhile under the highest emissions scenario, average prevalence falls by 20 cases per 1,000 children, marking a 9% reduction.

The graph below shows childhood malaria rates over 1990-2024 in the historical climate (blue) and in a world without climate change (grey). These estimates are shown relative to baseline prevalence across 1901-30.

After the year 2014, the plot shows projected future changes in malaria prevalence, relative to a 2015-20 baseline, in the low (purple), intermediate (pink) and high (green) scenarios.

Carlson emphasises that this does not mean that climate change is “good news” for healthcare in sub-Saharan Africa. He explains that climate change will bring a wide range of negative health impacts that will strain healthcare systems, adding:

“A world that is too hot for malaria is not a good world for the health of children.”

He also notes that climate change is “not the primary driving factor of malaria dynamics”. For example, he notes that malaria prevalence fell over 2000-15, by about 16 percentage points, after the disease was identified as a “critical global target of the Millennium Development Goals”.

This reduction is 200 times greater than the increase seen so far because of climate change, Carlson says. He adds:

“It would not be tremendously hard both to keep malaria out of new places and to eliminate it where it is maybe going to get a little bit of an assist from climate change.”

Dr Adugna Woyessa is a senior researcher at the Ethiopian Public Health Institute and was not involved in the study. He has previously carried out research on malaria in eastern Africa.

Woyessa praises the study, telling Carbon Brief that the research could bring about a “paradigm shift” in efforts to eliminate malaria. He argues that the study is a “tool for engaging giant development partners”, adding that “future work will be needed to situate these global trends in local contexts”.

Dr Janey Messina is an associate professor in the school of geography and the environment at the University of Oxford and was also not involved in the study. She praises the paper’s “strong” method.

However, she cautions that the findings “should not be interpreted as forecasts of total future malaria burden”, because they only model the impact of climate change on malaria, while excluding “social, demographic and public-health determinants”, such as inequality, migration, conflict and changing access to malaria interventions.

She adds:

“One of the paper’s most important messages is this: effective surveillance, prevention and treatment remain substantially more influential – and more actionable – than climate change alone.”

Related

Q&A: Europe’s May and June heatwave deaths – and how they were counted

17.07.2026

Extreme weather

Guest post: France’s June heatwave caused more than 2,700 heat-related deaths

07.07.2026

Health and society

Revealed: Floods have forced at least 67 closures at NHS hospitals since 2021

25.05.2026

Health and society

Climate change could lead to 500,000 ‘additional’ malaria deaths in Africa by 2050

28.01.2026

Health and society

The post Climate change is driving a ‘shift’ in childhood malaria risk across Africa appeared first on Carbon Brief.

Climate change is driving a ‘shift’ in childhood malaria risk across Africa