Whale and Dolphin Migrations are Being Disrupted by Climate Change

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Original article by Teresa Tomassoni republished from Inside Climate News under Creative Common License (CC BY-NC-ND 3.0)

A humpback whale jumps out of the waters of the Pacific Ocean near Cabo San Lucas, Mexico. Credit: Alfredo Martinez/Getty Images

Rising ocean temperatures, heatwaves and dwindling prey are forcing marine mammals into new and more dangerous waters, scientists warn.

For millennia, some of the world’s largest filter-feeding whales, including humpbacks, fin whales and blue whales, have undertaken some of the longest migrations on earth to travel between their warm breeding grounds in the tropics to nutrient-rich feeding destinations in the poles each year. 

“Nature has finely tuned these journeys, guided by memory and environmental cues that tell whales when to move and where to go,” said Trisha Atwood, an ecologist and associate professor at Utah State University’s Quinney College of Agriculture and Natural Resources. But, she said, climate change is “scrambling these signals,” forcing the marine mammals to veer off course. And they’re not alone. 

Earlier this year, Atwood joined more than 70 other scientists to discuss the global impacts of climate change on migratory species in a workshop convened by the United Nations Convention on the Conservation of Migratory Species of Wild Animals. The organization monitors and protects more than 1,000 species that cross borders in search of food, mates and favorable conditions to nurture their offspring. 

More than 20 percent of these species are on the brink of extinction. It was the first time the convention had gathered for such a purpose, and their findings, published this month in a report, were alarming. 

“Almost no migratory species is untouched by climate change,” Atwood said in an email to Inside Climate News. 

From whales and dolphins, to arctic shorebirds and elephants, all are affected by rising temperatures, extreme weather and shifting ecosystems, which are disrupting migratory routes and reshaping critical habitats across the planet. 

Asian elephants, for instance, are being driven to higher ground and closer to human settlements as they search for food and water amidst intensifying droughts, fueling more frequent human-elephant conflicts, the report found. Shorebirds are reaching their Arctic breeding grounds out of sync with the insect blooms their chicks depend on to survive. 

The seagrass meadows that migrating sea turtles and dugongs feed on are disappearing due to warmer waters, cyclones and sea level rise, according to the report. To date, around 30 percent of the world’s known seagrass beds have been lost, threatening not only the animals that depend on them, but also humans. These vital ecosystems store around 20 percent of the world’s oceanic carbon, in addition to supporting fisheries and protecting coastlines. 

A view of seagrass meadows found in the depths of Izmit Bay off the coast of Karamursel, Turkey. Credit: Tahsin Ceylan/Anadolu via Getty Images
A view of seagrass meadows found in the depths of Izmit Bay off the coast of Karamursel, Turkey. Credit: Tahsin Ceylan/Anadolu via Getty Images

Together, these examples reveal how climate change is tipping the delicate balance migratory species have long relied on to survive. 

“Climate change is disrupting this balance by altering when and where resources appear, how abundant they are, the environmental conditions species must endure, and the other organisms they interact with, reshaping entire networks of predators and competitors,” Atwood said. 

Especially amongst marine life. 

On the United States’ West Coast, for instance, Atwood said, warming waters are pushing juvenile great white sharks out of their traditional southern habitats. This shift has led to a sharp rise in sea otter deaths in Monterey Bay, California, where they are increasingly getting bitten by the sharks.

Whales and dolphins are particularly vulnerable species as rising temperatures threaten both their prey and their habitat, according to the report. 

Heatwaves in the Mediterranean are projected to reduce suitable habitat for endangered fin whales by up to 70 percent by mid-century as their prey dwindles or moves due to rising temperatures. In some places, such as the Northern Adriatic Sea, hotter temperatures may eventually prove intolerable for bottlenose dolphins. “Rising water temperatures could exceed the species’ physiological tolerance,” the report says, which also acknowledges that this is already happening in other parts of the world, such as the Amazon River. 

Two bottlenose dolphins play in the Mediterranean Sea off the coast of Tarifa, Spain on Sept. 21. Credit: Matthias Balk/picture alliance via Getty Images

In 2023, more than 200 river dolphins, which migrate seasonally between tributaries and lagoons in the Amazon, died due to record-high temperatures, along with much of their prey. In some areas, their shallow aquatic habitats exceeded 100 degrees Fahrenheit. “The river systems were unusually empty and dry and the animals got isolated,” said Mark Simmonds, scientific councilor for marine pollution for the U.N. convention, who led some of the discussions around climate change impacts on cetaceans at the workshop in February. “They lost the water that they would have been living in.” 

Loss of prey in traditional habitats is of particular concern for migrating marine mammals that are forced to follow their prey into new, and sometimes more perilous, waters. 

This is particularly evident in the case of critically endangered North Atlantic Right whales, which the report says are especially prone to ship strikes and entanglement in fishing gear as they pursue their prey—tiny crustaceans called copepods—which are moving towards cooler waters. There are fewer than 400 of the whales left.

The North Pacific humpback whales that feed off the coast of California are also at risk. 

Original article by Teresa Tomassoni republished from Inside Climate News under Creative Common License (CC BY-NC-ND 3.0)

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‘Profound concern’ as scientists say extreme heat ‘now the norm’ in UK

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https://www.theguardian.com/environment/2025/jul/14/profound-concern-as-scientists-say-extreme-heat-now-the-norm-in-uk

Weather records clearly show the UK’s climate is different now compared with just a few decades ago. Photograph: Geoffrey Swaine/Shutterstock

Increasing frequency of heatwaves and flooding raises fears over health, infrastructure and how society functions

Record-breaking extreme weather is the new norm in the UK, scientists have said, showing that the country is firmly in the grip of the climate crisis.

The hottest days people endure have dramatically increased in frequency and severity, and periods of intense rain have also ramped up, data from hundreds of weather stations shows. Heatwaves and floods leading to deaths and costly damage are of “profound concern” for health, infrastructure and the functioning of society, the scientists said.

The weather records clearly show the UK’s climate is different now compared with just a few decades ago, the scientists said, as a result of the carbon pollution emitted by burning fossil fuels.

The analysis found that the number of days with temperatures 5C above the average for 1961-1990 had doubled in the last 10 years. For days 8C above average, the number has trebled and for 10C above average it has quadrupled. The UK has also become 8% sunnier in the last decade.

The assessment, called the State of the UK Climate 2024 and published in the International Journal of Climatology, found the last three years were in the UK’s top five hottest years on record. The warmest spring on record was seen in 2024 although this has already been surpassed in 2025.

The UK has particularly long meteorological records and the Central England Temperature series is the longest instrumental record in the world. It shows that recent temperatures have far exceeded any in at least 300 years. However, today’s high temperatures are likely to be average by 2050, and cool by 2100, the scientists said.

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Actuaries and Scientists Warn Climate Shocks Risk ‘Planetary Insolvency’

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Original article by Jessica Corbett republished from Common Dreams under Creative Commons (CC BY-NC-ND 3.0). Published Jan 16, 2025

Gas company employees work in Malibu, California, after the Palisades Fire destroyed beach homes on January 12, 2025. (Photo: Frederic J. Brown/AFP via Getty Images)

A new report “shows a 50% GDP contraction between 2070 and 2090 unless an alternative course is chartered,” said the lead author.

U.K. actuaries and University of Exeter climate scientists on Thursday warned that “the risk of planetary insolvency looms unless we act decisively” and urged policymakers to “implement realistic and effective approaches to global risk management.”

Actuaries have developed techniques that “underpin the functioning of the global pension market with $55 trillion of assets, and the global insurance market, collecting $8 trillion of premiums annually, to help us manage risk,” Tim Lenton, University of Exeter’s climate change and Earth system science chair, noted in the foreword of a report released Thursday.

Planetary Solvency—Finding Our Balance With Nature is the fourth report for which the Institute and Faculty of Actuaries (IFoA) has collaborated with climate scientists. In financial terms, solvency is the ability of people or companies to pay their long-term debts. Co-authors of one of the previous publications coined the phrase planetary solvency, “setting out the idea that financial risk management techniques could be adapted to help society manage climate change and other risks.”

Three IFoA leaders—Kalpana Shah, Paul Sweeting, and Kartina Tahir Thomson—explained in their introduction to the latest report how “planetary solvency applies these techniques to the Earth system,” writing:

The essentials that support our society and economy all flow from the Earth system, commodities such as food, water, energy, and raw materials. The Earth system regulates the climate and provides a breathable atmosphere, it is the foundation that underpins our society and economy. Planetary solvency assesses the Earth system’s ability to continue supporting us, informed by planetary boundaries, tipping points in the Earth system, and other scientific discoveries to assess risks to this foundation—and thus to our society and the economy.

Our illustrative assessment of planetary solvency in this report shows a more fundamental, policy-led change of direction is required. Our current market-led approach to mitigating climate and nature risks is not delivering. There is an increasing risk of severe societal disruption (planetary insolvency), as our economic system drives further global warming and nature degradation.

“Impacts are already severe with unprecedented fires, floods, heatwaves, storms, and droughts,” the document points out, emphasizing that human activity—particularly burning fossil fuels—drives climate change and biodiversity loss. “If unchecked they could become catastrophic, including loss of capacity to grow major staple crops, multimeter sea-level rise, altered climate patterns, and a further acceleration of global warming.”

The report was released as wildfires ravage California and shortly after scientific bodies around the world concluded that 2024 was the hottest year on record and the first in which the average global temperature exceeded a key goal of the Paris agreement: 1.5°C above preindustrial levels. In the United States, experts identified 27 disasters with losses exceeding $1 billion.

“We risk triggering tipping points such as Greenland ice sheet melt, coral reef loss, Amazon forest dieback, and major ocean current disruption,” the new publication warns, adding that “tipping points can trigger each other,” and if multiple are triggered, “there may be a point of no return, after which it may be impossible to stabilize the climate.”

Food system shocks and more frequent and devastating disasters increase the risk of mass mortality for humanity—including due to hunger and infectious diseases—along with mass migration and conflict, the report highlights.

“Climate change risk assessment methodologies understate economic impact, as they often exclude many of the most severe risks that are expected and do not recognize there is a risk of ruin,” the document stresses. “They are precisely wrong, rather than being roughly right.”

Specifically, lead author and IFoA council member Sandy Trust said in a statement, “widely used but deeply flawed assessments of the economic impact of climate change show a negligible impact” on gross domestic product (GDP).

However, Trust continued, “the risk-led methodology, set out in the report, shows a 50% GDP contraction between 2070 and 2090 unless an alternative course is chartered.”

To mitigate the risk of planetary insolvency, the co-authors called on policymakers around the world to implement independent, annual assessments; set limits and thresholds that respect the planet’s boundaries; enhance governance structures to support planetary solvency; and “enhance policymaker understanding of ecological interdependencies, tipping points, and systemic risks so they understand why these changes are needed.”

They also underscored the need to limit global warming and avoid triggering tipping points with actions such as accelerating decarbonization, removing greenhouse gases from the atmosphere, restoring damaged ecosystems, and building resilience.

“You can’t have an economy without a society, and a society needs somewhere to live,” said Trust. “Nature is our foundation… Threats to the stability of this foundation are risks to future human prosperity which we must take action to avoid.”

Original article by Jessica Corbett republished from Common Dreams under Creative Commons (CC BY-NC-ND 3.0).

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How the weather got ‘stuck’ over the UK – and produced an unusually dry and warm spring

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Wildfires have ignited in forests and on moorland across the UK in recent months. LSP EM/Shutterstock

Simon H. Lee, University of St Andrews and Matthew Patterson, University of St Andrews

A “blocking” weather system lingering high above the UK has produced one of the driest, warmest and brightest starts to spring on record.

April 2025 was the sunniest since records began in 1910. This followed the third-sunniest March, and both months saw temperatures well above average nationwide. On May 1, the temperature reached 29.3°C in Kew Gardens in London – a new record for the date.

Meteorologists are warning of the potential for a summer drought, as the UK has seen roughly half its usual amount of rainfall for March and April. While farmers fret about this year’s harvest, some water companies are urging customers to help reservoir levels recover by limiting water use.

Meanwhile, wildfires have engulfed forest and moorland in areas of Scotland, Wales and England.

Two maps of the UK, showing mostly dark brown colours which indicate rainfall below 50% of normal.
Most of the UK has experienced a record-dry spring so far. Met Office

For several weeks, a stubborn area of high pressure over the UK has diverted the usual flow of mild, moist air from the North Atlantic like a boulder in a river. This is known as a blocking weather system.

Within it, air descends, warms and dries, which is why this weather pattern tends to be linked to heatwaves and drought. Blocking is usually persistent, making it seem like the weather is stuck.

Here’s how climate change may have played a role in setting up this unusual spring.


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The human fingerprint

The warming climate means that unusually warm weather is occurring more often and becoming more intense. At the same time, we can expect more periods of both severe drought and extreme rainfall. Sudden changes from drought to deluge, termed “weather whiplash”, are due to the intensification of the water cycle in a warmer atmosphere that can hold more water vapour.

However, certain weather patterns are necessary to produce extreme weather. More blocking events in future could increase the chance of heatwaves or drought. But are blocking weather patterns becoming more common?

It’s difficult to determine how weather patterns will change as a result of the rising concentration of greenhouse gases in the atmosphere, which is predominantly caused by the burning of fossil fuels.

Part of the difficulty arises from the fact that weather patterns vary year to year. Several years in a row with more blocking events than usual could make it seem like blocking is increasing due to climate change, but it could simply be down to chance.

As a result, it is difficult to detect the fingerprint of human activity from weather observations alone. For example, blocking weather patterns over Greenland during summer have happened more often in recent decades, which can enhance the melting of the ice sheet. But it isn’t clear that this trend is the result of human-induced climate change.

Climate models do suggest future changes in the occurrence of blocking, however. These computer simulations, consisting of equations that describe the fundamental physics of the atmosphere, are the main tool scientists use to perform experiments that parse how the climate will behave in future.

A map of pressure anomalies over Europe.
The blocking system is visible in the area of high pressure over Britain and Ireland. National Centers for Environmental Prediction/National Center for Atmospheric Research/NOAA Physical Sciences Laboratory, CC BY

When scientists run climate model simulations with increased greenhouse gas concentrations the results consistently show a decrease in blocking events. But blocking generally happens more often in real life than model simulations, which reduces the confidence scientists have in future projections.

Keeping track of the jet stream

The movement of weather systems in Earth’s mid-latitudes – including over the UK – is linked to the jet stream, which is a fast-flowing river of air driven by the contrast in temperature between the poles and mid-latitudes.

Some researchers have suggested that, because the Arctic is warming faster than the tropics, the jet stream may weaken and become more “wavy”, increasing the occurrence of blocking events, contrary to what most climate models show.

Outside of the scientific community, this idea has become popular. However, the hypothesis remains controversial among scientists, and observational evidence has weakened in recent years.

In fact, around ten kilometres above the Earth’s surface, near commercial aircraft cruising altitudes, the opposite trends are occurring: the temperature difference between the Arctic and mid-latitudes is increasing, acting to increase the strength of the jet stream.

There are considerable challenges with understanding how climate change is affecting the large-scale atmospheric patterns which drive the weather we experience. These include large natural variability and imperfect climate models. Models mostly suggest a decline in blocking events with climate change, though this remains relatively uncertain compared with other aspects of the science.

Overall, we can be confident that climate change is bringing warmer conditions in all seasons. Scientists also have strong evidence to suggest that drought conditions will become more common. These changes are already affecting food production, energy generation and water availability and these impacts will continue to worsen with climate change.


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Simon H. Lee, Lecturer in Atmospheric Science, University of St Andrews and Matthew Patterson, Research Fellow in climate and machine learning, University of St Andrews

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Continue ReadingHow the weather got ‘stuck’ over the UK – and produced an unusually dry and warm spring

Children born in 2020 will face ‘unprecedented exposure’ to climate extremes

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Original article republished from Carbon Brief under a CC license

Children drink water from a pipeline in the village of Afraaga, Somaliland. Credit: Joe Giddens / Alamy Stock Photo

Children born in 2020 will face “unprecedented exposure” to extreme weather events, including heatwaves, droughts and wildfires, even if warming is limited to 1.5C above pre-industrial temperatures.

That is according to a new study, published in Nature, which calculates the number of unprecedented extreme events that people born in different decades and countries might live through.

Using a case study focused on Brussels, the researchers find that people born in 2020 will experience an “unprecedented” 11 heatwaves in their lifetime – even if global warming is limited to 1.5C by the end of the century.

In contrast, in a pre-industrial climate, a person living in the Belgian capital would likely experience just three such heatwaves, according to the study.

More than half of children born in 2020 – around 62 million people – will experience “unprecedented lifetime exposure” to heatwaves, even if warming is limited to 1.5C, the study finds. 

However, this number nearly doubles to 111 million under a scenario where warming hits 3.5C.

The study also analyses crop failures, river floods, tropical cyclones, wildfires and droughts. 

The research “helps the climate community build new narratives that better clarify the impacts [of climate change] on younger generations and vulnerable populations”, one expert who was not involved in the study tells Carbon Brief.

Intergenerational justice

As the planet warms, extreme weather events such as heatwaves, floods and droughts are becoming more intense, more frequent and lasting longer.

popular 2021 study found that children born in the 21st century will be exposed to more extreme weather events in their lifetimes than their parents and grandparents.

The paper found that in a scenario of 3C of warming above pre-industrial levels, a child who turns six in 2020 will experience twice as many wildfires and tropical cyclones, three times more river floods, four times more crop failures, five times more droughts and 36 times more heatwaves over their lifetime than a six-year-old living in a pre-industrial climate.

The authors also found a “particularly strong increase” in children’s future exposure to extremes in the Middle East and North Africa.

The lead author of the study – Prof Wim Thiery from Vrije Universiteit Brussel – told Carbon Brief at the time that today’s youth will live “an unprecedented life”, in which they will “face conditions which older generations have never experienced”.

Four years later, Dr Luke Grant – a researcher in Thiery’s team – has led a new study building on the ideas of the 2021 paper.

Grant tells Carbon Brief that rather than counting the number of extreme events that an individual might experience, his new study counts the number of people that reach an “unprecedented state” of exposure to extremes.

Prof Kaveh Madani is the director of the UN University Institute for Water, Environment and Health and was not involved in the study. He tells Carbon Brief that the paper “helps the climate community build new narratives that better clarify the impacts [of climate change] on younger generations and vulnerable populations”.

The authors define “exposure” as the number of extreme events that a person experiences in their lifetime, relative to the number they would have experienced in a pre-industrial climate.

“Unprecedented lifetime exposure” is defined as exposure so high that it has only a one-in-10,000 chance of happening in a world without any greenhouse gas emissions.

‘Unprecedented lifetime exposure’

The authors present a case study of extreme heat in Brussels, Belgium, to explain their method.

They define a heatwave as a three-day extreme heat event, which reaches average temperatures that would be expected once per century in a pre-industrial climate.

Using models from the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP), the authors calculate heatwave frequency in a world without climate change. They also assess scenarios in which warming is limited to 1.5C, 2.5C and 3.5C by the end of the century.

They combine this data with demographic information, including how many people are born in the country each year and their average life expectancy, using data from sources including the ISIMIP database and UN population estimates and projections.

In a world without climate change, the study finds that a person born in 1960 in Brussels would have a one-in-10,000 chance of experiencing six of the pre-defined heatwaves in their lifetime. Any member of this “birth cohort” who experiences more than six heatwaves in their lifetime has therefore faced “unprecedented lifetime exposure” to extreme heat, according to the study.

The authors find that a person born in Brussels in 1960 is likely to experience three heatwaves on average during their lives under all of the three future warming pathways– meaning that they are unlikely to face “unprecedented lifetime exposure” to heat.

By contrast, the researchers find that many younger age cohorts will experience unprecedented heatwave exposure. For many younger age cohorts, lifetime exposure to heatwaves is greater for higher warming pathways. 

For example, people born in Brussels in 2020 will experience 11 heatwaves in their lifetime if global warming is limited to 1.5C by the end of the century. If warming rises to 2.5C or 3.5C, they could experience 18 or 26 heatwaves, respectively. 

The graphic below shows heat exposure since birth in Brussels for three “birth cohorts” of 1960 (bottom row), 1990 (middle row) and 2020 (top row). It presents three future scenarios, in which warming is limited to 1.5C (blue), 2.5C (yellow) and 3.5C (red) by 2100. The dotted line shows the threshold for an “unprecedented” lifetime exposure to extreme heat. 

Lifetime exposure to unprecedented heat for people born in Brussels
Lifetime exposure to unprecedented heat for people born in Brussels in 1960 (bottom row), 1990 (middle row) and 2020 (top row), under scenarios that limit warming to 1.5C (blue), 2.5C (yellow) and 3.5C (red) by the year 2100. The dotted line shows the threshold for an “unprecedented” lifetime exposure to extreme heat. Source: Grant et al (2025).

Heat exposure

The authors repeat their analysis across the Earth’s entire land surface, by dividing it into grid cells and using location-specific temperature and demographic data. 

Of the 81 million people born in 1960, they find that 13 million are likely to face unprecedented exposure to heatwaves in their lifetimes. They add that for this age cohort, lifetime exposure to unprecedented extremes does not vary depending on the warming scenario.

However, 21st century warming has a significant effect on exposure for younger generations. Under a 1.5C warming pathway, 52% of people born in 2020 will face unprecedented exposure to heatwaves. This rises to 92% under a 3.5C warming scenario.

The study adds:

“This implies that 111 million children born in 2020 will live an unprecedented life in terms of heatwave exposure in a world that warms to 3.5C versus 62 million in a 1.5C pathway.”

The charity Save the Children has published a report which unpacks the findings of the study. The graphic below, from the report, shows the percentage of people from different countries born in 2020 who will face unprecedented lifetime exposure to heatwaves under the 1.5C (top), 2.5C (middle) and 3.5C (bottom) warming scenarios.

Each circle shows a country, indicated by its three-letter countries code. The size of the circle indicates the number of people in the country. Darker circles indicate higher-income countries. 

Circles on the right hand side of the graphic indicate that more than half of the country’s 2020 cohort will be exposed to unprecedented heatwaves in their lifetime. 

The percentage of people born in 2020 who will face unprecedented lifetime exposure to heatwaves
The percentage of people born in 2020 who will face unprecedented lifetime exposure to heatwaves under the 1.5C (top), 2.5C (middle) and 3.5C (bottom) warming scenarios. Each circle indicates a country, indicated by its three-letter countries code. The size of the circle indicates the number of people in the country. Darker circles indicate higher-income countries. Source: Save the Children

“The evidence is now inescapable that heatwaves impact every community around the world,” Dr Luke Harrington, a senior lecturer in environmental science at the University of Waikato, who was not involved in the study, tells Carbon Brief. He adds: 

“This paper offers the clearest view that climate change is verifiably unfair: those who have done the least to contribute to rising global temperatures will experience the most extreme impacts.”

From floods to fires

The authors apply the same method to five other climate extremes – crop failure, wildfires, droughts, floods and tropical cyclones.

The graphic below shows the key findings. The coloured portion of the bar shows the number of people born in 2020 who will face unprecedented exposure to each extreme under a 1.5C warming pathway. The dark green and light green bars show the additional exposure under 2.7C and 3.5C warming.

Number of people born in 2020 who will face “unprecedented lifetime exposure” to heatwaves, crop failures, river floods, tropical cyclones, wildfires and droughts
Number of people born in 2020 who will face “unprecedented lifetime exposure” to heatwaves, crop failures, river floods, tropical cyclones, wildfires and droughts under 1.5C 2.7C and 3.5C warming. Source: Save the Children

The authors find that unprecedented lifetime exposure to heatwaves will affect the most people, with 62 million people born in 2020 likely to face unprecedented exposure to heat in their lifetimes if warming is limited to 1.5C.

This is followed by crop failures and river floods, which will impact 23 million and 10 million people from the 2020 birth cohort under the 1.5C warming pathway, respectively.

Lead author Grant tells Carbon Brief that he is “most confident” about his heatwave findings because temperature is a “basic” metric for climate models to “get right”.

Meanwhile, extremes such as crop failure depend on a range of factors including soil moisture, land-atmosphere interactions and rainfall, which can make it harder for the models to accurately capture changes, Grant explains.

Vulnerability

The authors also assess how “socioeconomic vulnerability” affects their findings using a global deprivation index – a tool which measures the level of disadvantage and hardship experienced by individuals or communities in a particular geographic area.

The authors use the index to identify the 20% most and least vulnerable people in each age cohort. They find that the most vulnerable groups are overwhelmingly from African countries.

The authors also conclude that “socioeconomically vulnerable people have a consistently higher chance of facing unprecedented lifetime heatwave exposure compared to the least vulnerable members of their generation”.

The graph below, taken from a news and views article about the study, shows the percentage of high vulnerability (red) and low vulnerability (pink) people in each age cohort who would be exposed to unprecedented heat, under a 2.7C warming scenario. 

The percentage of high vulnerability (red) and low vulnerability (pink) people in each age cohort who would be exposed to unprecedented heat,
The percentage of high vulnerability (red) and low vulnerability (pink) people in each age cohort who would be exposed to unprecedented heat, under a 2.7C warming scenario. Source: Gualdi and Muttarak (2025).

Dr Marina Romanello, a research fellow at the University College London and research director of the Lancet Countdown on Health and Climate Change who was not involved in the study, tells Carbon Brief that the paper “is an important addition to the scientific literature, showing how our delays in tackling climate change are putting the future of our children at risk”. 

She adds:

“The authors have used well-established models to project future health threats, framing them around what matters the most: the wellbeing, health and survival of present and future generations.”

Grant, L. et al. (2025) Global emergence of unprecedented lifetime exposure to climate extremes, Nature, doi:10.1038/s41586-025-08907-1

Original article republished from Carbon Brief under a CC license

Continue ReadingChildren born in 2020 will face ‘unprecedented exposure’ to climate extremes