When flooding strikes, it can devastate vast areas, taking lives, homes and possessions with it.
Multiple factors affect the scale of the social and economic damage that flooding causes, such as climate change, land-use change and the flood protection measures in place.
In a new study, published in Science Advances, my colleagues and I attempt to disentangle the factors contributing to more than 1,700 floods in Europe over 1950-2020.
Our findings show that there has been an overall reduction in deaths and economic damage over this 70-year period – even though population and economic growth means the maximum value of possible losses has increased.
This is linked to the extent to which society has adapted to climate change.
Our study finds that – in most regions – flood impacts have been affected primarily by direct human actions, such as land-use change, vulnerability reduction and catchment alteration, rather than long-term changes to river levels or sea levels.
Other factors, including climate change and alterations to river catchments, had an important role in certain places, but were not a factor on a continent-wide scale.
What influences flood losses?
Dozens of floods occur in Europe every year, though the magnitude of the socioeconomic impacts they cause varies considerably from year to year.
Floods can happen in any country, though they are less common in north-eastern Europe, especially since climate change has reduced snow cover and, hence, reduced spring snowmelt. In the hot and mountainous south of Europe, flash floods are a major risk, causing most fatalities in Europe. In north-western Europe the risk of coastal flooding, increased by global sea level rise, is higher than in other parts of the continent.
Our study looks at 1,729 floods that took place across Europe over a 70 year-period, drawn from the Historical Analysis of Natural Hazards in Europe (HANZE) database. We estimate that this list covers the vast majority of all flood impacts in Europe since 1950.
We find that, in absolute terms, direct economic damage from floods in Europe has increased considerably, from an estimated €37bn in the 1950s (at 2020 prices) to €92bn in the 2000s and €71bn in 2010s.
Yet, in relative terms, the annual losses from floods have fallen. Direct economic damage from floods fell to 0.04% of Europe’s gross domestic product (GDP) in the 2010s, down from 0.11% in the 1950s.
Meanwhile, the risk of dying in a flood has also declined more than six-fold since the 1950s.
Six long-term drivers
First, it is worth noting that each of the 1,729 events in our study were the result of a unique combination of natural and socioeconomic factors under various flood management regimes.
However, we can explore how trends in economic and social damages from floods across Europe have been influenced by different drivers. For this, we turn to the evolving science of attribution research.
Extreme weather attribution research covers a diverse set of qualitative and quantitative approaches to estimate the contribution of individual drivers – such as climate change or socioeconomic factors – to observed impacts. Most studies focus on attribution to climate change, but such approaches are often insufficient to explain the magnitude of flood losses.
Our study investigates six long-term drivers that could have explained the trends in flood impacts in Europe over a 70-year period. These are:
- Long-term climate change
- Human interventions in river catchments
- Population and economic growth
- Land-use change
- Flood protection levels
- Flood vulnerability
To do so, we use hydrological and socioeconomic models driven by observations of climate, economic and other trends.
In all cases, we evaluate the drivers against the climate and socioeconomic conditions of the year 1950 to capture how their importance might have changed over time.
The first driver we look at – and the one that is typically of most interest in attribution studies – is long-term changes to the climate. This includes changes in the probability of extreme river discharges, storm surges, wave heights and global sea level rise.
The study looks at both the fingerprint of human-caused climate change – the 1950-2020 period is when most of global warming has occurred – but also incorporates natural variations of the climate.
Here, we find climate change has mostly worsened flood impacts, especially for levels of economic damage.
However, there is strong variation in Europe. While climate change has led to more substantial flood impacts in north-west Europe, the inverse was true for several countries in southern Europe. This is largely due to an increase in the dryness of the climate.
Human factors
Next we look at human interventions in river catchments, such as reservoir construction and land-use change, which alter the movement and distribution of water across large areas.
Here, we find that these interventions had opposite effects.
Across Europe, land-use change contributed to larger flood impacts over the study period. This was largely due to a rapid increase in “soil sealing” – the covering of soil for housing, roads or other construction work.
However, the construction of large reservoirs – most of which were built after 1950 – has reduced flood volumes, helping to reduce flood impacts, particularly in central Europe.
Population growth has increased flood impacts in almost all countries (with the main exception being Germany because of population decline in the east of the country). In addition, economic growth means the maximum value of possible losses to floods – or “flood exposure” – has increased across the continent.
That said, when considering losses relative to the size of the economy or population, the change in spatial distribution of people becomes more important.
For example, there has been more development in floodplains than outside of them, which – when combined with structural factors, such as the shift from agriculture to industry and from industry to services – has contributed to an overall increase in flood impacts.
However, this did not occur in all countries and did not apply to fatalities, which narrowly reduced across Europe over the study period due to changes in population distribution.
Adaptation
The final two drivers investigated were related to how society has adapted to flood risks.
One method is improving structural flood protection through dykes and reservoirs. (In a 2024 study, we estimated that flood protection has improved in Europe since 1950, even if more for coastal than river floods.)
We also see this effect in this study, though it is not as pronounced. This is because we only look at floods that did occur – meaning that protection measures were not sufficient to prevent them.
Nonetheless, we find that better protection has reduced the extent and, therefore, the impact of floods in most European countries, except some in central and northern Europe.
Our final driver was vulnerability to floods, defined as the relative impact of flooding on population and assets at a given hydrological intensity.
This factor heavily depends on the level of preparedness and adaptation as well as the capacity to respond to a flood. For instance, small adaptations of buildings that prevent water from flowing into it could substantially reduce the share of the building value that is lost in the flood.
In the most recent decade, floods caused an estimated 74-75% fewer fatalities and smaller economic loss than if they happened in 1950 at the same level of exposure – thanks to lower vulnerability. This reduction was found across the continent – indicating that certain universal changes were responsible for this process.
Our study was not able to link this progress to individual measures, but obvious candidates are creation of early warning systems, more capable emergency services, improved disaster response and uptake of private precautionary measures by households and companies after previous experiences of flooding.
The figure below shows the contribution of the six drivers (from left to right) for three types of impacts: fatalities (top), population affected (middle) and economic losses (bottom) to all floods that have occurred in each country between 1950 and 2020.
The shading indicates whether the driver increased (red) or decreased (blue) impacts.
Attribution of contribution to impacts (in rows) of different drivers (A to F), by country, expressed as percent change, relative to the counterfactual scenario of no change in the individual driver since 1950. Source: Paprotny, D et al. (2025)
Solutions reaching their limit?
Our findings indicate the crucial role that adaptation has had on containing growth in flood losses that could have been induced by a larger population and economy.
Still, this positive development should not be taken for granted. Our results show a considerable slowdown in the reduction of losses from better flood protection or lower levels of vulnerability in the most recent two decades. This could indicate that existing solutions are reaching their limits.
However, we find that southern and eastern Europe still has higher vulnerability compared with western Europe – showing potential for further improvements in those regions.
Recent major floods, such as the 2021 event in western Europe, have raised questions about existing levels of preparedness, while highlighting the role of climate change in increasing the impacts of those events.
Our study shows that adaptation works in Europe, but that greater efforts will be needed to ensure it continues to do so.
The post Guest post: How adaptation has cut flood deaths and losses in Europe appeared first on Carbon Brief.
Guest post: How adaptation has cut flood deaths and losses in Europe
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 would work towards “actively yet prudently”.
Around the world
- EU RULES: The European Commission has proposed new “made in Europe” rules to support domestic low-carbon industries, “against fierce competition from China”, reported Agence France-Presse. Carbon Brief examined what it means for climate efforts.
- RECORD HEAT: The US National Oceanic and Atmospheric Administration has said there is a 50-60% chance that the El Niño weather pattern could return this year, amplifying the effect of global warming and potentially driving temperatures to “record highs”, according to Euronews.
- FLAGSHIP FUND: The African Development Bank’s “flagship clean energy fund” plans to more than double its financing to $2.5bn for African renewables over the next two years, reported the Associated Press.
- NO WITHDRAWAL: Vanuatu has defied US efforts to force the Pacific-island nation to drop a UN draft resolution calling on the world to implement a landmark International Court of Justice (ICJ) ruling on climate, according to the Guardian.
98
The number of nations that submitted their national reports on tackling nature loss to the UN on time – just half of the 196 countries that are part of the UN biodiversity treaty – according to analysis by Carbon Brief.
Latest climate research
- Sea levels are already “much higher than assumed” in most assessments of the threat posed by sea-level rise, due to “inadequate” modelling assumptions | Nature
- Accelerating human-caused global warming could see the Paris Agreement’s 1.5C limit crossed before 2030 | Geophysical Research Letters covered by Carbon Brief
- Future “super El Niño events” could “significantly lower” solar power generation due to a reduction in solar irradiance in key regions, such as California and east China | Communications Earth & Environment
(For more, see Carbon Brief’s in-depth daily summaries of the top climate news stories on Monday, Tuesday, Wednesday, Thursday and Friday.)
Captured
UK greenhouse gas emissions in 2025 fell to 54% below 1990 levels, the baseline year for its legally binding climate goals, according to new Carbon Brief analysis. Over the same period, data from the World Bank shows that the UK’s economy has expanded by 95%, meaning that emissions have been decoupling from growth.
Spotlight
Bristol’s ‘pioneering’ community wind turbine
Following the recent launch of the UK government’s local power plan, Carbon Brief visits one of the country’s community-energy success stories.
The Lawrence Weston housing estate is set apart from the main city of Bristol, wedged between the tree-lined grounds of a stately home and a sprawl of warehouses and waste incinerators. It is one of the most deprived areas in the city.
Yet, just across the M5 motorway stands a structure that has brought the spoils of the energy transition directly to this historically forgotten estate – a 4.2 megawatt (MW) wind turbine.
The turbine is owned by local charity Ambition Lawrence Weston and all the profits from its electricity sales – around £100,000 a year – go to the community. In the UK’s local power plan, it was singled out by energy secretary Ed Miliband as a “pioneering” project.
‘Sustainable income’
On a recent visit to the estate by Carbon Brief, Ambition Lawrence Weston’s development manager, Mark Pepper, rattled off the story behind the wind turbine.
In 2012, Pepper and his team were approached by the Bristol Energy Cooperative with a chance to get a slice of the income from a new solar farm. They jumped at the opportunity.
“Austerity measures were kicking in at the time,” Pepper told Carbon Brief. “We needed to generate an income. Our own, sustainable income.”
With the solar farm proving to be a success, the team started to explore other opportunities. This began a decade-long process that saw them navigate the Conservative government’s “