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.
A 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.
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 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.
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.
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.”
The post Children born in 2020 will face ‘unprecedented exposure’ to climate extremes appeared first on Carbon Brief.
Children born in 2020 will face ‘unprecedented exposure’ to climate extremes
Drought and heatwaves occurring together – known as “compound” events – have “surged” across the world since the early 2000s, a new study shows.
Compound drought and heat events (CDHEs) can have devastating effects, creating the ideal conditions for intense wildfires, such as Australia’s “Black Summer” of 2019-20 where bushfires burned 24m hectares and killed 33 people.
The research, published in Science Advances, finds that the increase in CDHEs is predominantly being driven by events that start with a heatwave.
The global area affected by such “heatwave-led” compound events has more than doubled between 1980-2001 and 2002-23, the study says.
The rapid increase in these events over the last 23 years cannot be explained solely by global warming, the authors note.
Since the late 1990s, feedbacks between the land and the atmosphere have become stronger, making heatwaves more likely to trigger drought conditions, they explain.
One of the study authors tells Carbon Brief that societies must pay greater attention to compound events, which can “cause severe impacts on ecosystems, agriculture and society”.
Compound events
CDHEs are extreme weather events where drought and heatwave conditions occur simultaneously – or shortly after each other – in the same region.
These events are often triggered by large-scale weather patterns, such as “blocking” highs, which can produce “prolonged” hot and dry conditions, according to the study.
Prof Sang-Wook Yeh is one of the study authors and a professor at the Ewha Womans University in South Korea. He tells Carbon Brief:
“When heatwaves and droughts occur together, the two hazards reinforce each other through land-atmosphere interactions. This amplifies surface heating and soil moisture deficits, making compound events more intense and damaging than single hazards.”
CDHEs can begin with either a heatwave or a drought.
The sequence of these extremes is important, the study says, as they have different drivers and impacts.
For example, in a CDHE where the heatwave was the precursor, increased direct sunshine causes more moisture loss from soils and plants, leading to a drought.
Conversely, in an event where the drought was the precursor, the lack of soil moisture means that less of the sun’s energy goes into evaporation and more goes into warming the Earth’s surface. This produces favourable conditions for heatwaves.
The study shows that the majority of CDHEs globally start out as a drought.
In recent years, there has been increasing focus on these events due to the devastating impact they have on agriculture, ecosystems and public health.
In Russia in the summer of 2010, a compound drought-heatwave event – and the associated wildfires – caused the death of nearly 55,000 people, the study notes.
The record-breaking Pacific north-west “heat dome” in 2021 triggered extreme drought conditions that caused “significant declines” in wheat yields, as well as in barley, canola and fruit production in British Columbia and Alberta, Canada, says the study.
Increasing events
To assess how CDHEs are changing, the researchers use daily reanalysis data to identify droughts and heatwaves events. (Reanalysis data combines past observations with climate models to create a historical climate record.) Then, using an algorithm, they analyse how these events overlap in both time and space.
The study covers the period from 1980 to 2023 and the world’s land surface, excluding polar regions where CDHEs are rare.
The research finds that the area of land affected by CDHEs has “increased substantially” since the early 2000s.
Heatwave-led events have been the main contributor to this increase, the study says, with their spatial extent rising 110% between 1980-2001 and 2002-23, compared to a 59% increase for drought-led events.
The map below shows the global distribution of CDHEs over 1980-2023. The charts show the percentage of the land surface affected by a heatwave-led CDHE (red) or a drought-led CDHE (yellow) in a given year (left) and relative increase in each CDHE type (right).
The study finds that CDHEs have occurred most frequently in northern South America, the southern US, eastern Europe, central Africa and south Asia.
Threshold passed
The authors explain that the increase in heatwave-led CDHEs is related to rising global temperatures, but that this does not tell the whole story.
In the earlier 22-year period of 1980-2001, the study finds that the spatial extent of heatwave-led CDHEs rises by 1.6% per 1C of global temperature rise. For the more-recent period of 2022-23, this increases “nearly eightfold” to 13.1%.
The change suggests that the rapid increase in the heatwave-led CDHEs occurred after the global average temperature “surpasse[d] a certain temperature threshold”, the paper says.
This threshold is an absolute global average temperature of 14.3C, the authors estimate (based on an 11-year average), which the world passed around the year 2000.
Investigating the recent surge in heatwave-leading CDHEs further, the researchers find a “regime shift” in land-atmosphere dynamics “toward a persistently intensified state after the late 1990s”.
In other words, the way that drier soils drive higher surface temperatures, and vice versa, is becoming stronger, resulting in more heatwave-led compound events.
Daily data
The research has some advantages over other previous studies, Yeh says. For instance, the new work uses daily estimations of CDHEs, compared to monthly data used in past research. This is “important for capturing the detailed occurrence” of these events, says Yeh.
He adds that another advantage of their study is that it distinguishes the sequence of droughts and heatwaves, which allows them to “better understand the differences” in the characteristics of CDHEs.
Dr Meryem Tanarhte is a climate scientist at the University Hassan II in Morocco, and Dr Ruth Cerezo Mota is a climatologist and a researcher at the National Autonomous University of Mexico. Both scientists, who were not involved in the study, agree that the daily estimations give a clearer picture of how CDHEs are changing.
Cerezo-Mota adds that another major contribution of the study is its global focus. She tells Carbon Brief that in some regions, such as Mexico and Africa, there is a lack of studies on CDHEs:
“Not because the events do not occur, but perhaps because [these regions] do not have all the data or the expertise to do so.”
However, she notes that the reanalysis data used by the study does have limitations with how it represents rainfall in some parts of the world.
Compound impacts
The study notes that if CDHEs continue to intensify – particularly events where heatwaves are the precursors – they could drive declining crop productivity, increased wildfire frequency and severe public health crises.
These impacts could be “much more rapid and severe as global warming continues”, Yeh tells Carbon Brief.
Tanarhte notes that these events can be forecasted up to 10 days ahead in many regions. Furthermore, she says, the strongest impacts can be prevented “through preparedness and adaptation”, including through “water management for agriculture, heatwave mitigation measures and wildfire mitigation”.
The study recommends reassessing current risk management strategies for these compound events. It also suggests incorporating the sequences of drought and heatwaves into compound event analysis frameworks “to enhance climate risk management”.
Cerezo-Mota says that it is clear that the world needs to be prepared for the increased occurrence of these events. She tells Carbon Brief:
“These [risk assessments and strategies] need to be carried out at the local level to understand the complexities of each region.”
The post Heatwaves driving recent ‘surge’ in compound drought and heat extremes appeared first on Carbon Brief.
Heatwaves driving recent ‘surge’ in compound drought and heat extremes
Greenhouse Gases
DeBriefed 6 March 2026: Iran energy crisis | China climate plan | Bristol’s ‘pioneering’ wind turbine
Welcome to Carbon Brief’s DeBriefed.
An essential guide to the week’s key developments relating to climate change.
This week
Energy crisis
ENERGY SPIKE: US-Israeli attacks on Iran and subsequent counterattacks across the Middle East have sent energy prices “soaring”, according to Reuters. The newswire reported that the region “accounts for just under a third of global oil production and almost a fifth of gas”. The Guardian noted that shipping traffic through the strait of Hormuz, which normally ferries 20% of the world’s oil, “all but ground to a halt”. The Financial Times reported that attacks by Iran on Middle East energy facilities – notably in Qatar – triggered the “biggest rise in gas prices since Russia’s full-scale invasion of Ukraine”.
‘RISK’ AND ‘BENEFITS’: Bloomberg reported on increases in diesel prices in Europe and the US, speculating that rising fuel costs could be “a risk for president Donald Trump”. US gas producers are “poised to benefit from the big disruption in global supply”, according to CNBC. Indian government sources told the Economic Times that Russia is prepared to “fulfil India’s energy demands”. China Daily quoted experts who said “China’s energy security remains fundamentally unshaken”, thanks to “emergency stockpiles and a wide array of import channels”.
‘ESSENTIAL’ RENEWABLES: Energy analysts said governments should cut their fossil-fuel reliance by investing in renewables, “rather than just seeking non-Gulf oil and gas suppliers”, reported Climate Home News. This message was echoed by UK business secretary Peter Kyle, who said “doubling down on renewables” was “essential” amid “regional instability”, according to the Daily Telegraph.
China’s climate plan
PEAK COAL?: China has set out its next “five-year plan” at the annual “two sessions” meeting of the National People’s Congress, including its climate strategy out to 2030, according to the Hong Kong-based South China Morning Post. The plan called for China to cut its carbon emissions per unit of gross domestic product (GDP) by 17% from 2026 to 2030, which “may allow for continued increase in emissions given the rate of GDP growth”, reported Reuters. The newswire added that the plan also had targets to reach peak coal in the next five years and replace 30m tonnes per year of coal with renewables.
ACTIVE YET PRUDENT: Bloomberg described the new plan as “cautious”, stating that it “frustrat[es] hopes for tighter policy that would drive the nation to peak carbon emissions well before president Xi Jinping’s 2030 deadline”. Carbon Brief has just published an in-depth analysis of the plan. China Daily reported that the strategy “highlights measures to promote the climate targets of peaking carbon dioxide emissions before 2030”, which China said it wou