Published

9 months ago

September 23, 2025

Alice Rush

Fungi are learning to adapt to climate change, posing a major threat to human health.

Fungal infections range from minor conditions, such as athlete’s foot, to life-threatening respiratory diseases and bloodstream infections.

Fungi are known for their ability to adjust to – and thrive in – new and changing environments.

Now, they are learning to adapt to the rising temperatures, changing rainfall patterns and extreme weather events that characterise a warming planet.

This is increasing their ability to colonise and cause disease in the human body.

However, there is a severe lack of diagnostics, treatments and vaccines available for fungal infections – and fungal resistance to existing drugs is on the rise.

An increase in fungal infections driven by climate change could also have devastating consequences for agriculture, damaging crops and threatening food security.

New fungal pathogens

Fungi are one of five “kingdoms” of life on Earth – putting them in a distinct category separate from animals or plants.

There are millions of fungal species – from saccharomyces cerevisiae, or baker’s yeast, to penicillium chrysogenum, which is the source of the antibiotic penicillin.

Fungal infections can be transmitted to humans through direct contact in the environment, with contaminated surfaces or via infected individuals.

Historically, most fungi do not cause disease in humans, meaning they are not “pathogenic”.

This is because – unlike viruses and bacteria – most fungi cannot survive or spread in body temperatures of 37C.

But, as global temperatures rise, some fungi are adapting to survive in hotter environments, including the human body.

(How fungi adapt to their environments is still not fully understood. However, their large genomes and diverse metabolic pathways – the chemical reactions which allow organisms to function – are thought to play a key role in their ability to survive and grow in a wide range of conditions.)

An example of this is candida auris, a fungal infection that emerged simultaneously on three continents in the late 2000s. The fungus mostly infects people with weakened immune systems and is a real concern as it can cause bloodstream infections. It is a serious problem in intensive care units, where the fungus sticks to medical equipment and grows rapidly.

Many infection, prevention and control measures are unable to get rid of it. Candida auris is already resistant to several antifungal drugs, making it very challenging to treat. One study in Oman, for example, recorded a fatality rate over more than 50%.

Due to lack of surveillance and routine monitoring, we do not know exactly how many people are impacted by candida auris infections.

To address this, the World Health Organization Global Antimicrobial Resistance and Use Surveillance System (WHO-GLASS) – a programme that provides a standardised approach to collect and analyse data for antimicrobial resistance surveillance – has included a protocol for candida auris.

Candida auris is one of four fungal species identified by the World Health Organization (WHO) as a “critical” threat to public health, alongside aspergillus fumigatus, candida albicans and cryptococcus neoformans.

Scientists have pointed to the likelihood that the emergence of candida auris is being driven by rising temperatures caused by climate change.

A 2022 study noted that higher temperatures driven by human-caused climate change may have added “selective pressure” on candida auris – leading to the spread of strains “adapted to salinity and higher temperatures – similar to the conditions found in the human body”.

The emergence of candida auris is just one example of how climate change is exacerbating fungal infection.

A study currently undergoing peer review suggests that – without effective strategies to tackle climate change – the aspergillus family could expand its reach to more northerly swathes of Europe, Asia and the Americas, exposing more people to life-threatening respiratory infections as temperatures rise.

Aspergillus infections can cause permanent damage to lungs and lead to serious illness in individuals with existing respiratory conditions or weakened immune systems.

Extreme weather

Rising temperatures are not the only cause of rising fungal infections linked to climate change.

Changing rainfall patterns, increasing humidity and worsening extreme weather events are also driving fungal pathogens to new areas.

Heavy rainfall, flooding and humidity leads to increased moisture in homes, increasing the growth of indoor mould. Mould – which encompasses a diverse group of fungal species – can cause substantial health impacts when inhaled for those with underlying health conditions, such as asthma.

Meanwhile, extreme weather events, such as wildfires and floods, transport fungal pathogens to new regions by spreading spores far beyond where they would typically be found. This increases the threat fungi pose to both human health and agriculture.

For instance, the fungus coccidioides, which is found in soils in the south-western US and parts of central and South America, causes valley fever – a lung infection which can be fatal to humans and animals.

Outbreaks occur when extreme events, such as wildfires, disturb large amounts of soil and spread fungal spores into the air. These enter the human body when inhaled. Cases are often unreported, but it is estimated that the fungi causes around 206,000-360,000 cases per year in the US.

The fungus thrives in a hot and dry climate. Coccidioides is now being seen in regions that would not normally support its growth, as the climate heats up.

A 2019 study used climate models to project that the range of valley fever could expand into more northerly US states such as Idaho, Wyoming and Nebraska. It also estimates that, by 2100, cases across the US could rise by approximately 50% as more regions develop climates suitable for transmission.

Threatening food security

Fungal pathogens also threaten human health indirectly by damaging harvests and causing a range of plant diseases, including blights, root rot and mildew.

Blight tomato disease. Credit: Botany vision / Alamy Stock Photo

Fungi are a key part of soil ecosystems, but plant pathogenic fungi can cause growers to lose between 10-23% of their crops every year – and a further 10-20% after they are harvested, as food that is incorrectly stored goes mouldy at different points of the supply chain.

Rising temperatures can spread and introduce more pathogens to an area, which can reduce harvests and, in some cases, wipe out entire crop families. This could result in food insecurity globally and economic instability in regions that rely on agricultural exports.

Modern agriculture’s reliance on growing genetically uniform crops, known as monocultures, puts the global food system at increased risk of fungal disease, as pathogens learn how to colonise crops.

Developments in the global banana market are a prominent example of the threat posed by fungus to crops. In the 1950s, the Gros Michel banana – once the main export variety of banana – was wiped out by a disease caused by the fungus fusarium oxysporum.

Now, the banana variety that was grown and exported in its place – the Cavendish banana – is under threat by a new strain of fusarium. This poses a major threat to the global banana trade, given that the Cavendish banana accounts for 47% of banana production and virtually all bananas supplied to the US and Europe.

In another example, the fusarium graminearum fungus, which flourishes in wet conditions and warm temperatures, causes a disease that is thought to cause wheat and barley yield losses amounting to more than $1bn every year.

Rising antifungal resistance

The spread of fungal infections caused by climate change is particularly concerning given the lack of available treatment options, as well as limited awareness among the public and healthcare professionals.

Most healthcare professionals receive little training around how to identify fungal infections, leading to delayed diagnosis and treatment. In the developing world, fungal infections can be deadly because both awareness and access to diagnostic tests are lacking.

There are just four types of antifungal drugs and no approved fungal vaccines.

Antifungal treatments are harder to develop than antibiotics because fungi are more biologically similar to humans than plants – making them difficult to kill without harming human cells.

Meanwhile, resistance to the antifungal drugs that are available is growing.

The fungicides used to kill fungi in agriculture often share “modes of action” with medical antifungals. The overuse of these fungicides has led to fungi in the environment building up their resistance – creating hardier fungi that are more difficult to treat in clinical settings.

As climate change puts additional stress on the food system, the risks and benefits of using fungicides to ensure food security need to be balanced with safeguarding the effectiveness of antifungal drugs.

However, there is limited communication between agricultural and medical sectors around how to juggle these priorities.

And yet – despite all these challenges – fungal infections receive a fraction of the funding and attention that bacterial or viral diseases do.

Fungi that tackle climate change

Fungi have historically been an asset in medical research – most notably the discovery of the drug penicillin. They could also prove valuable in the fight against climate change.

Some fungi are used to suppress populations of pests or pathogens in agriculture. This method – known as natural biocontrol – uses fungi, or other forms of naturally occurring organisms – such as bacteria, insects or viruses – as a replacement for chemical pesticides.

Natural biocontrol is seen as a more environmentally friendly method for treating crops than manmade chemicals because the organisms break down naturally in the environment and do not leave toxic residues in the soil.

Meanwhile, researchers have also found that mycorrhizal fungi – which grow in association with plant roots – store roughly 13bn tonnes of carbon (GtC) – equivalent to 36% of annual global fossil fuel emissions. The fungus does this by absorbing carbon from plants and locking it in their underground networks and soil, where it stays stable for long periods.

There are groups looking at how the mycorrhizal fungi could be harnessed to help deliver decarbonisation – similar to tree planting.

However, more research is needed to better understand the valuable properties of fungi, including how they could be part of “nature-based solutions” to help tackle climate change.

Discovering the unknown

There is still a lot that remains unknown about fungi. Scientists estimate that less than 10% of all species have been identified globally.

Fungi are essential to healthy ecosystems. They recycle nutrients by breaking down organic matter and play a critical role in the carbon cycle.

But climate change is disrupting this balance. Rising temperatures and environmental shifts threaten to wipe out some fungal species before they’re even discovered, while enabling others to thrive in new – and often harmful – ways.

These changes signal deep trouble for the natural world.

It is, therefore, critical that more scientific attention is paid to the risks and opportunities of fungi as they learn to adapt to a warmer climate.

The post Guest post: Fungal infections are adapting to climate change – and threatening public health appeared first on Carbon Brief.

Guest post: Fungal infections are adapting to climate change – and threatening public health

Climate Change

UN asks AI companies to reveal full environmental impacts

Published

8 hours ago

June 23, 2026

Alice Rush

The head of the United Nations has launched an initiative aimed at holding artificial intelligence companies accountable for their exploding environmental impacts, including their carbon emissions, the amount of water and land used for data centres, and the energy they consume.

During a speech at London Climate Action Week on Tuesday, António Guterres noted that AI can accelerate climate solutions, among other key challenges, and said its potential must be harnessed.

“But AI is also hungry for land, water and power,” he emphasised, adding that the data centres needed to run AI models already consume more electricity than most countries.

The UN Secretary-General repeated a call he first made in July 2025 for all big AI companies to commit to power every data centre with renewable energy by 2030.

Some tech firms have announced they are sourcing or building out clean energy to run their hubs, but growing power demand is also contributing to gas-fired generation in the US, according to data from Global Energy Monitor.

The International Energy Agency (IEA) estimates that data centres are set to more than double the emissions from the electricity they use between 2024 and 2030 in a high-growth scenario. But AI’s use could lead to far larger reductions in the energy sector through efficiency gains if adopted widely.

Jun 23, 2026

Energy

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Comment

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By reviving the problematic industry in the name of energy security, China runs the risk of higher emissions, stranded assets and setting back its ambitions as a clean energy leader

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Oceans

Mombasa ocean summit drives progress on marine protection, but threats persist

At the 11th Our Ocean conference in Kenya, its founder John Kerry says the ocean must become central to climate solutions and needs to be looked after

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‘No more hidden costs’

Proposing the new “AI Environmental Transparency Initiative” on Tuesday, Guterres also urged big AI firms companies to measure and publicly disclose the full environmental impact of their systems, including their carbon, water, and land footprints.

“No more hidden costs. No more shifting the burden onto those least able to bear it. It is time to come clean,” he said in a major speech on responding to the world’s twin climate and energy crises. “If AI is to help build a better future, it must be honest about what it costs us now.”

A report issued earlier this month by the UN University Institute for Water, Environment and Health noted that most current assessments of AI’s environmental cost focus on carbon emissions from training models. But, it added, this misses a substantial part of the picture.

Every kilowatt-hour of electricity for AI also carries a water footprint, from cooling and generation, and a land footprint, from infrastructure and supply chains, it said.

Explainer: Will AI data centres make or break the energy transition?

The report estimated that AI data centres globally could consume 945 terawatt-hours of electricity annually by 2030 – more power than all but five countries and roughly twice France’s 2025 consumption.

Offsetting this carbon footprint by 2030 would require growing some 6.7 billion trees over 10 years, it calculated. Producing power for the data centres would consume water equal to the basic needs of 1.3 billion people in sub-Saharan Africa for a year and take up land of more than 14,500 square kilometers, roughly twice the Jakarta metropolitan area.

The European Union said earlier this month it will develop minimum energy-efficiency standards for both new and existing data centres, with a “needs assessment” due by 2027, Reuters reported. It’s also planning ⁠a sustainability label for data centres, covering criteria including water use and clean energy supply – but that has been delayed.

US community push-back

Asked after his speech what the response had been, the UN chief said “we’ll see”, without giving more details.

But, he argued that, in his view, the push for transparency “is perfectly reasonable and even positive for the AI industry, because eventually some people will say that they consume much more than they really do”. “I think the truth is essential,” he added.

Concerns about the environmental impacts of AI and the infrastructure needed to run the technology have led to growing opposition in some communities, especially in the US.

This month, Monterey Park in Los Angeles County was the first city in the United States to enact a citywide prohibition on data centres through a voter-approved ballot measure. The developers behind a proposed centre in the area had already pulled the project in April amid an increasingly hostile local environment and regulatory uncertainty.

The vote that stopped a data center: US communities query resource-hungry AI

According to nonprofit Data Center Watch, around $64 billion-worth of data centre projects nationwide were delayed or blocked between May 2024 and March 2025 as communities pushed back against them.

Industry lobby groups argue that data centres can provide economic benefits in their host communities. According to the US-based Data Center Coalition, which represents big operators and developers, data centres generate tax revenue, support construction and technical jobs, and provide infrastructure needed for cloud computing, scientific research and AI development.

The industry has also challenged claims that data centers necessarily raise electricity costs for households.

Force for good?

The UN chief said benefits can be few in the places that are home to the data centre, while “communities are often left in the dark about the environmental impact of the infrastructure rising around them”.

Guterres said companies have an “obligation” to be clear and open about the services they are offering but also the level of resources they require.

“Transparency is essential for the decisions that communities must make – and transparency is essential even for the future of artificial intelligence, and to make sure that artificial intelligence is essentially a force for good,” he told an audience of climate professionals in London

A senior UN official told journalists ahead of Tuesday’s announcement that the AI industry has started to talk about and disclose some of their impacts, but those efforts are not yet comprehensive enough.

The hope is that the new initiative will “encourage the industry to come together and take further action on it”, the official said.

The post UN asks AI companies to reveal full environmental impacts appeared first on Climate Home News.

UN asks AI companies to reveal full environmental impacts

Climate Change

Prof Philippe Ciais: The world’s most highly cited climate scientist

Published

11 hours ago

June 23, 2026

Alice Rush

Phillipe Ciais has spent almost four decades researching the planet’s carbon cycle – and the ways in which humans have been impacting its balance.

Based at the Laboratoire des Sciences du Climat et de l’Environnement (LSCE) on the outskirts of Paris, Ciais (pronounced “see-es”) has been listed as an author on more than 1,300 peer-reviewed studies.

In fact, analysis of Carbon Brief’s Cosmos database reveals that – by some distance – he is the most highly cited climate scientist in the world.

In a wide-ranging interview, he discusses:

The post Prof Philippe Ciais: The world’s most highly cited climate scientist appeared first on Carbon Brief.

https://www.carbonbrief.org/prof-philippe-ciais-the-worlds-most-highly-cited-climate-scientist/

Climate Change

Cited 23 June 2026: Project Cosmos launch | Science ‘under attack’ at Bonn | Emissions inequality

Published

12 hours ago

June 23, 2026

Alice Rush

Welcome to Cited, your essential guide to new climate research.

In the news

SCIENCE ‘UNDER ATTACK’: Climate Home News reported that “dozens” of countries called out “coordinated attacks” aimed at “undermining the role of climate science” at UN climate talks in Bonn, Germany, last week. According to the outlet, the countries said that UN decision-making had to remain based on the “best available science”, including the reports of the Intergovernmental Panel on Climate Change. One negotiator said that India and Saudi Arabia “opposed calls in draft texts to encourage scientific work on scenarios that would minimise the magnitude and duration of any overshoot of 1.5C”, the article noted. For more, read Carbon Brief’s summary of the negotiations.

REPORT OPPOSITION: “Oil industry allies” in the US are targeting a report on extreme weather attribution, due to be published by the National Academies of Sciences, Engineering and Medicine, according to Politico. The outlet reported that the “heightened scrutiny – which involves a secretive opposition research group scouring scientists’ emails – has prompted two people to leave the 15-person panel tasked with producing the report”. Separately, the Guardian reported that the Trump administration has “reversed its decision” to dismantle the Ocean Observatories Initiative, a $368m deep-sea observation system.

SUPER EL NIÑO: BBC News reported that the US National Oceanic and Atmospheric Administration announced that El Niño had “officially begun”. Forecasts suggest the event could be among the “strongest ever recorded”, it added. Meanwhile, a “vigorous debate” is taking place about whether climate change is making the El Niño phenomenon more intense, according to the New York Times. The outlet explained that some scientists see the run of “comparatively strong” El Niño events in recent decades as an indication that “climate change is supercharging El Niño”. However, it added that “others say there is no clear evidence to support that theory”.

Research picks

Water

Global sea level rise has nearly tripled the number of days since the 1970s when coastal water levels have surpassed average tide gauge readings | Science Advances
As the Arctic warms, increased iceberg activity could “reshape” deep-sea habitats and “elevate” navigational hazards as maritime traffic expands | Nature
Sea level rise has quadrupled the frequency of extreme coastal sea-level events since the year 1900 | Nature Climate Change

Inequality

The top 10% of consumers are responsible for $1.7-5.7tn of environmental damage each year, surpassing international climate and biodiversity financing gaps | Communications Sustainability
Calculating an individual’s emissions based on their asset ownership suggests that wealthier people are responsible for an even higher share of global greenhouse gas emissions than indicated by past studies | Nature Climate Change
A plan that places equity at the “centre” of climate adaptation efforts in cities is needed to address the “stark disparities” between “affluent” and “disadvantaged” urban communities’ ability to prepare for extreme heat | PLOS Climate

Extremes

In the western US, 42% of burned area over 2001-24 occurred during, and immediately following, heatwaves | Science Advances
“Hot-to-wet” whiplash events have become more frequent across Australia over the past century, with south-eastern Australia emerging as a hotspot | Journal of Climate
Rapid urbanisation, combined with more intense rainfall from tropical cyclones, have increased people’s exposure to “extreme” rainfall from tropical cyclones across China | Journal of Hydrometeorology

Captured

Chart showing that population growth and a warming world have driven up the number of people exposed to extreme heat since the 1970s

One billion additional people face at least one day of “extreme heat stress” every year compared to the 1970s, according to research published in Nature Climate Change.

The chart shows changes in “strong” (top), “very strong” (middle) and “extreme” (bottom) heat stress, defined as a “universal thermal climate index” above 32C, 38C and 46C, respectively. The grey bar shows the percentage of the global population exposed to at least one, 30 or 90 days of heat stress in 1970. The light and dark blue bars show the number of additional people experiencing heat stress over 2015-24 due to population growth and rising global temperatures, respectively.

10%

Equivalent damage to the UK’s GDP caused by climate change if global warming reaches 4C by 2100, according to new research in Nature Climate Change. The study estimates a range of 2-20%.

Spotlight

Introducing: Project Cosmos

Carbon Brief explains how it built a major new database of climate science research and unveils a new ranking of the 500 most highly cited publications, authors and institutions in climate science.

This week, Carbon Brief launched Project Cosmos – the world’s largest and most complete database of climate change research.

The database features more than 1.8m academic papers, books and reports, capturing the vast body of human knowledge about climate change that has accumulated over more than a century of academic study.

The climate science “universe” is based on reports from the Intergovernmental Panel on Climate Change (IPCC), which are recognised as the world’s most authoritative summaries of the latest climate science.

Since its first report was published in 1990, humanity’s knowledge about human-caused climate change has ballooned. The IPCC has published six sets of reports in total – each one longer than the last.

In total, IPCC reports reference more than 100,000 other papers, books and reports. This is the core of our climate science universe. Carbon Brief then built on this core, by looking at four other sources of data. Read more about how the Cosmos database was created here.

Every single publication in the Cosmos database is linked to at least one other through references. Visualising these links reveals a “galaxy” of references. In the image above, each colour and cluster reveals different topics and densities of research. Explore the galaxy in an interactive map here.

Cosmos 500

As part of an initial wave of preliminary analysis to demonstrate the scope of the Project Cosmos database, Carbon Brief has ranked the 500 most highly cited publications, authors and institutions in the database.

The most highly cited climate scientist is Prof Philippe Ciais, who has spent almost four decades researching the planet’s carbon cycle – and the ways in which humans have been impacting its balance. Carbon Brief recently interviewed Ciais in Paris.

The US tops the tables for the most highly-cited authors and institutions. Almost half of the 500 most highly-cited authors are from US institutions. This raises particular concerns for the future of climate science, as American climate scientists and institutions are coming under attack under the Trump administration.

Experts from global south countries account for only 4% of all authors in the Cosmos 500. China stands out as the most highly-cited global south country. Meanwhile, only 10% of authors in the Cosmos 500 are women.

There are many possibilities for future avenues of research using the Cosmos database. Over time, the database could be used to reveal, for example, how interest in different areas of climate science has changed over time, plus identify potential knowledge gaps and, thus, opportunities for future research.

Carbon Brief invites researchers – including academics, journalists and analysts – to submit their own proposals for co-authored studies, literature reviews and analytical projects.

Preprints to watch

Carbon Brief’s pick of new papers still going through peer review

Regional reductions in aerosol emissions can “temporarily amplify” the likelihood of record-breaking heat events | Environmental Research: Climate
Analysis of Reddit posts suggests the Fridays for Future movement has created “wider awareness” of global warming by drawing attention to climate change and “climate actions” | npj climate action
Periods of simultaneous low wind and solar power generation, known as “renewable energy droughts”, will “intensify progressively” as the planet warms | Nature portfolio

Noticeboard

28-30 June: Seventh global conference on climate and sustainable development goal synergies, Bangkok, Thailand
29 June-1 July: Exeter climate conference, Exeter, UK
29 June-1 July: National Academy of Sciences hybrid workshop on seabed critical mineral resources, Irvine, US
30 June: Submission deadline for abstracts for MedCLIVAR conference, scheduled for 21-25 September in Limassol, Cyprus
30 June: Application deadline for postdoctoral position in ice-ocean interactions at the Physics Laboratory of Ecole Normale Supérieure de Lyon | Salary: €3,071-4,714 per month. Location: Lyon, France
30 June: Submissions open for abstracts for the pan-African conference on environment, climate change and health, scheduled for 21-24 October in Nairobi, Kenya
8 July: Application deadline for position as research officer in climate science and law at the Grantham Research Institute | Salary: £43,277-51,714. Location: London, UK
10 July: Application deadline for position as associate or senior editor at Nature Water | Salary: Unknown. Location: Shanghai, Beijing or Milan