“Exceptionally heavy” rainfall that led to deadly flooding across southern Africa in recent weeks was made more intense by a combination of climate change and La Niña.

This is according to a rapid attribution study by the World Weather Attribution service.

From late December 2025 to early January, south-eastern Africa was hit hard by intense downpours that resulted in more than a year’s worth of rain falling in some areas in just a few days, according to the study.

This led to severe flooding that left at least 200 people dead, thousands sheltering in temporary accommodation and tens of thousands of hectares of farmland waterlogged.

The analysis finds that periods of intense rainfall over southern Africa have become 40% more severe since pre-industrial times, according to observations.

The authors say they were unable to calculate how much of this increase was driven specifically by climate change, due to limitations in how climate models simulate African rainfall.

However, the study notes that the researchers “have confidence that climate change has increased both the likelihood and the intensity” of the rainfall.

The authors also note that the El Niño-Southern Oscillation phenomenon played a role in the “devastating” flooding, estimating that a La Niña event made the rainfall around five times more likely.

Major disruption

The heavy rainfall started on 26 December last year and intensified from early January. The most-extreme rainfall took place between 10 and 19 January.

The countries most affected by the floods, and analysed by the study, are Eswatini, Mozambique, South Africa and Zimbabwe, with some areas receiving up to 200mm of rain, according to the study authors.

Study author Bernardino Nhantumbo – a researcher at Mozambique’s National Institute of Meteorology – told a press briefing that in just two or three days, some areas recorded the amount of rainfall that is “expected for the whole rainy season”.

The map below shows the areas most affected by intense rainfall over 10-19 January. Darker blue indicates a greater accumulation of rainfall, while light green indicates less rainfall. The pink box shows the study area.

In Mozambique, the floods damaged nearly 5,000km of roads, which has hindered the transport of goods and affected pharmaceutical supply chains, the study says. In Zimbabwe, bridges, roads and infrastructure were “significantly damaged or destroyed”.

More than 75,000 people have been affected by the floods in Mozambique, according to the study. BBC News reported the floods were the worst seen “in a generation” in the country.

Dr Izidine Pinto, a climate scientist from Mozambique currently working at the Royal Netherlands Meteorological Institute, told a press briefing that the country was particularly affected because it “lies downstream of major river basins”.

The flooding prompted Mozambique’s education minister to consider rescheduling the start of the academic year, according to Channel Africa.

In South Africa, the country’s weather service said that areas receiving more than 50mm of rain over 11-13 January were “widespread”, with some places seeing up to 200mm.

South Africa’s Kruger National Park – the largest national park in South Africa – was severely damaged by floods and temporarily closed after several rivers burst their banks, reported TimesLIVE.

The South African news outlet quoted environment minister Willie Aucamp as saying: “The indication is that it will take as long as five years to repair all the bridges and roads and other infrastructure.”

Extreme rainfall

The peak of the rainy season in southern Africa falls between December and February.

To put the extreme rainfall into its historical context and determine how unlikely it was, the authors analysed a timeseries of 10-day maximum rainfall data for the December-February season.

They find that in today’s climate, extreme rainfall events of the scale seen this year in southern Africa would be expected only once every 50 years.

They add that such events have become “significantly more intense”, with observational data showing a 40% increase in rainfall severity since pre-industrial times.

The map below shows accumulated rainfall over Eswatini, Mozambique, South Africa and Zimbabwe over 10-19 January, as a percentage of the average December-February rainfall for the region over 1991-2020.

Green shading indicates that the rainfall in 2026 was higher than in 1991-2020, while brown indicates that it was lower. The red box indicates the study region.

The study explains that in January and February, rainfall patterns in southern Africa are “strongly influenced” by the El Niño-Southern Oscillation (ENSO), a naturally occurring climate phenomenon that affects global temperatures and regional weather patterns.

La Niña is the “cool” phase of ENSO, which typically brings wetter weather to southern Africa.

Pinto told the press briefing that “most past extreme rainfall events [in the region] have occurred during La Niña years”.

The authors estimate that the current weak La Niña event made the extreme rainfall five times more likely and increased the intensity of the event by around 22%.

For attribution studies, which identify the “fingerprint” of human-caused climate change on extreme weather events, scientists typically use climate models to simulate and compare worlds with and without global warming.

However, many models have limitations in their simulations of African rainfall. In this study, the authors found that the models available to them cannot “adequately capture” the influence of ENSO on rainfall in the region.

Study author Prof Fredi Otto, a professor in climate science at the Imperial College London, told a press briefing that these limitations are “well known”. They stem, in part, because the models were “developed outside of Africa” by modellers with different priorities, she explained.

This means that the authors were unable to calculate how much more intense or likely the rainfall event was specifically as a result of human-caused warming.

However, Otto explained that the authors are “very, very confident that climate change did increase the likelihood and intensity of the rainfall” to some extent. This is because the observations all show an increase in rainfall over time and other existing literature supports this assumption, she added.

She told the press briefing that the results of this study were “definitely not 100% satisfactory”, adding that this study will “definitely not be the last of its kind in this region”.

(These findings are yet to be published in a peer-reviewed journal. However, the methods used in the analysis have been published in previous attribution studies.)

Vulnerability

The study warns that the flooding “exposed deep and persistent social vulnerability in the region”.

The authors say that a large proportion of the population – especially in urban areas – live in poor housing with “inadequate planning and insufficient provision of basic services”.

Paola Emerson, head of office at the UN Office for the Coordination of Humanitarian Affairs (OCHA) in Mozambique, told a UN press briefing about the flooding that nearly 90% of people in the country live in traditional adobe houses that “basically melt after a few days’ rains”.

In a WWA press release, study author Nhantumbo explained:

“When 90% of homes are made of sun-dried earth, they simply cannot withstand this much rain. The structural collapse of entire villages is a stark reminder that our communities and infrastructure are now being tested by weather they are just not designed to endure.”

Study author Renate Meyer – an adviser with the conflict and climate team at the Red Cross Red Crescent Centre – said in a WWA press briefing that the “recurring frequency of hazards such as drought and extreme rainfall have had a significant impact on communities experiencing, amongst others, displacement, health challenges, socioeconomic loss and psychological distress”.

For example, the World Health Organization (WHO) said in a press release that the event had disrupted access to health services and increased the risks of water- and mosquito-borne diseases, as well as respiratory infections across southern Africa.

Meyer explained that the countries included in this study have “substantial populations living below or near the poverty line with limited savings, low insurance cover and a high dependence on climate sensitive livelihoods”.

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The post Climate change and La Niña made ‘devastating’ southern African floods more intense appeared first on Carbon Brief.

Climate change and La Niña made ‘devastating’ southern African floods more intense

Climate change could lead to half a million more deaths from malaria in Africa over the next 25 years, according to new research.

The study, published in Nature, finds that extreme weather, rising temperatures and shifting rainfall patterns could result in an additional 123m cases of malaria across Africa – even if current climate pledges are met.

The authors explain that as the climate warms, “disruptive” weather extremes, such as flooding, will worsen across much of Africa, causing widespread interruptions to malaria treatment programmes and damage to housing.

These disruptions will account for 79% of the increased malaria transmission risk and 93% of additional deaths from the disease, according to the study.

The rest of the rise in malaria cases over the next 25 years is due to rising temperatures and shifting rainfall patterns, which will change the habitable range for the mosquitoes that carry the disease, the paper says.

The majority of new cases will occur in areas already suitable for malaria, rather than in new regions, according to the paper.

The study authors tell Carbon Brief that current literature on climate change and malaria “often overlooks how heavily malaria risk in Africa is today shaped by climate-fragile prevention and treatment systems”.

The research shows the importance of ensuring that malaria control and primary healthcare is “resilient” to the extreme weather, they say.

Malaria in a warming world

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

In 2024, Africa was home to 95% of malaria cases and deaths. Children under the age of five made up three-quarters of all African malaria deaths.

The disease is transmitted to humans by bites from mosquitoes infected with the malaria parasite. The insects thrive in high temperatures of around 29C and need stagnant or slow-moving water in which to lay their eggs. As such, the areas where malaria can be transmitted are heavily dependent on the climate.

There is a wide body of research exploring the links between climate change and malaria transmission. Studies routinely find that as temperatures rise and rainfall patterns shift, the area of suitable land for malaria transmission is expanding across much of the world.

Study authors Prof Peter Gething and Prof Tasmin Symons are researchers at the Curtin University’s school of population health and the Malaria Atlas Project from the The Kids Research Institute, Australia.

They tell Carbon Brief that this approach does not capture the full picture, arguing that current literature on climate change and malaria “often overlooks how heavily malaria risk in Africa is today shaped by climate-fragile prevention and treatment systems”.

The paper notes that extreme weather events are regularly linked to surges in malaria cases across Africa and Asia. This is, in-part, because storms, heavy rainfall and floods leave pools of standing water where mosquitoes can breed. For example, nearly 15,000 cases of malaria were reported in the aftermath of Cyclone Idai hitting Mozambique in 2019.

However, the study authors also note that weather extremes often cause widespread disruption, which can limit access to healthcare, damage housing or disrupt preventative measures such as mosquito nets. These factors can all increase vulnerability to malaria, driving the spread of the disease.

In their study, the authors assess both the “ecological” effects of climate change – the impacts of temperature and rainfall changes on mosquito populations – and the “disruptive” effects of extreme weather.

Mosquito habitat

To assess the ecological impacts of climate change, the authors first identify how temperature, rainfall and humidity affect mosquito lifecycles and habitats.

The authors combine observational data on temperature, humidity and rainfall, collected over 2000-22, with a range of datasets, including mosquito abundance and breeding habitat.

The authors then use malaria infection prevalence data, collected by the Malaria Atlas Project, which describes the levels of infection in children aged between two and 10 years old.

Symons and Gething explain that they can then use “sophisticated mathematical models” to convert infection prevalence data into estimates of malaria cases.

Comparing these datasets gives the authors a baseline, showing how changes in climate have affected the range of mosquitoes and malaria rates across Africa in the early 21st century.

The authors then use global climate models to model future changes over 2024-49 under the SSP2-4.5 emissions pathway – which the authors describe as “broadly consistent with current international pledges on reduced greenhouse gas emissions”.

The authors also ran a “counterfactual” scenario, in which global temperatures do not increase over the next 25 years. By comparing malaria prevalence in their scenarios with and without climate change, the authors could identify how many malaria cases were due to climate change alone.

Overall, the ecological impacts of climate change will result in only a 0.12% increase in malaria cases by the year 2050, relative to present-day levels, according to the paper.

However, the authors say that this “minimal overall change” in Africa’s malaria rates “masks extensive geographical variation”, with some areas seeing a significant increase in malaria rates and others seeing a decrease.

Disruptive extremes

In contrast, the study estimates that 79% of the future increase in malaria transmission will be due to the “disruptive” impacts of more frequent and severe weather extremes.

The authors explain that extreme weather events, such as flooding and cyclones, can cause extensive damage to housing, leaving people without crucial protective equipment such as mosquito nets.

It can also destroy other key infrastructure, such as roads or hospitals, preventing people from accessing healthcare. This means that in the aftermath of an extreme weather event, people face a greater risk of being infected with malaria.

The climate models run by the study authors project an increase in “disruptive” extreme weather events over the next 25 years.

For example, the authors find that by the middle of the century, cyclones forming in the Indian Ocean will become more intense, with fewer category 1 to category 4 events, but more frequent category 5 events. They also find that climate change will drive an increase in flooding across Africa.

The study finds that without mitigation measures, these disruptive events will drive up the risk of malaria – especially in “main river systems” and the “cyclone-prone coastal regions of south-east Africa”.

Between 2024 and 2050, 67% of people in Africa will see their risk of catching malaria increase as a result of climate change, the study estimates.

The map below shows the percentage change in malaria transmission rate in the 2040s due to the disruptive impacts of climate change alone (left) and a combination of the disruptive and ecological impacts (right), compared to a scenario in which there is no change in the climate. Red and yellow indicate an increase in malaria risk, while blue indicates a reduction.

Colours in lighter shading indicate lower model confidence, while stronger colours indicate higher model confidence.

The maps show that the “disruptive” effects of climate change have a more uniform effect, driving up malaria risk across the entire continent.

However, there is greater regional variation when these effects are combined with “ecological” drivers.

The authors find that warming will increase malaria risk in regions where the temperature is currently too low for mosquitoes to survive. This includes the belt of lower latitude southern Africa, including Angola, southern Democratic Republic of Congo (DRC) and Zambia, as well as highland areas in Burundi, eastern DRC, Ethiopia, Kenya and Rwanda.

Meanwhile, they find that warming will drive down malaria transmission in the Sahel, as temperatures rise above the optimal range for mosquitoes.

Rising risk

The combined “disruptive” and “ecological” impacts of climate change will drive an additional 123m “clinical cases” of malaria across Africa, even if the current climate pledges are met, the study finds.

This will result in 532,000 additional deaths from malaria over the next 25 years, if the disease’s mortality rate remains the same, the authors warn.

The graph below shows the increase in clinical cases of malaria projected across Africa over the next 25 years, broken down into the different ecological (yellow) and disruptive (purple) drivers of malaria risk.

However, the authors stress that there are many other mechanisms through which climate change could affect malaria transmission – for example, through food insecurity, conflict, economic disruption and climate-driven migration.

“Eradicating malaria in the first half of this century would be one of the greatest accomplishments in human history,” the authors say.

They argue that accomplishing this will require “climate-resilient control strategies”, such as investing in “climate-resilient health and supply-chain infrastructure” and enhancing emergency early warning systems for storms and other extreme weather.

Dr Adugna Woyessa is a senior researcher at the Ethiopian Public Health Institute and was not involved in the study. He tells Carbon Brief that the new paper could help inform national malaria programmes across Africa.

He also suggests that the findings could be used to guide more “local studies that address evidence gaps on the estimates of climate change-attributed malaria”.

Study authors Symons and Gething tell Carbon Brief that during their study, they interviewed “many policymakers and implementers across Africa who are already grappling with what climate-resilient malaria intervention actually looks like in practice”.

These interventions include integrating malaria control into national disaster risk planning, with emergency responses after floods and cyclones, they say. They also stress the need to ensure that community health workers are “well-stocked in advance of severe weather”.

The research shows the importance of ensuring that malaria control and primary healthcare is “resilient” to the extreme weather, they say.

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The post Climate change could lead to 500,000 ‘additional’ malaria deaths in Africa by 2050 appeared first on Carbon Brief.

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

We handpick and explain the most important stories at the intersection of climate, land, food and nature over the past fortnight.

This is an online version of Carbon Brief’s fortnightly Cropped email newsletter. Subscribe for free here. This is the last edition of Cropped for 2025. The newsletter will return on 14 January 2026.

Key developments

High Seas Treaty enters force

OCEAN BOOST: The High Seas Treaty – formally known as the “biodiversity beyond national jurisdiction”, or “BBNJ” agreement – entered into force on 17 January, following its ratification by 60 states, reported Oceanographic Magazine. The treaty establishes a framework to protect biodiversity in international waters, which make up two-thirds of the ocean, said the publication. For more, see Carbon Brief’s explainer on the treaty, which was agreed in 2023 after two decades of negotiations.

DEEP-SEA MINING: Meanwhile, the US – which is not a party to the BBNJ’s parent Law of the Sea – is pushing on with an effort to accelerate permitting for companies wanting to hunt for deep-sea minerals in international waters, reported Reuters. The newswire described it as a “move that is likely to face environmental and legal concerns”.

UK biodiversity probe

SECURITY RISKS: The global decline of biodiversity and potential collapse of ecosystems pose serious risks to national security in the UK, a report put together by government intelligence experts has concluded, according to BBC News. The report was due to be published last autumn, but was “suppressed” by the prime minister’s office over fears it was “too negative”, said the Times.
COLLAPSE CONCERNS: Following a freedom-of-information (FOI) request, the government published a 14-page “abridged” version of the report, explained the Times. A fuller version seen by both the Times and Carbon Brief looked in detail at the potential security consequences of ecosystem collapse, including shifting global power dynamics, more migration to the UK and the risk of “protests over falling living standards”.

News and views

• OZ BUSHFIRES: Bushfires continued to blaze in Victoria, Australia, amid record-breaking heat, said the Guardian. A recent rapid attribution analysis found that the “extreme” Australian heat in early January was made around five times more likely by fossil-fuelled climate change.
• MERCO-SOURED: On 17 January, the EU signed its “largest-ever trade accord” with the Mercosur bloc of countries – Argentina, Brazil, Paraguay and Uruguay – after 25 years of negotiations, per Reuters. On 21 January, amid looming new US sanctions, EU lawmakers voted to send the pact to the European Court of Justice, which could delay the deal by almost two years, according to the New York Times.
• SOY IT ISN’T SO: Meanwhile, the Guardian reported that UK and EU supermarkets have “urged” traders who had “abandoned” the Amazon soya moratorium to stick to its core principles: “not to source the grain from Amazon land cleared after 2008”. 
• WATER ‘BANKRUPTCY’: A new UN report warned that the world is facing irreversible “water bankruptcy” caused by overextracting water reserves, along with shrinking supplies from lakes, glaciers, rivers and wetlands, Reuters reported. Lead author Prof Kaveh Madani told the Guardian that the situation is “extremely urgent [because] no one knows exactly when the whole system would collapse”.
• KRUGER UNDER WATER: Flood damages to South Africa’s Kruger National Park could “take years to repair” and cost more than $30m, said the country’s environment minister, quoted in Reuters. Rivers running through the park “burst their banks” and submerged bridges, with “hippos seen…among treetops”, it added.
• FORESTS VS COPPER: A Mongabay report examined how “community forests stand on the frontline” of critical-minerals mining in the Democratic Republic of the Congo’s copper-cobalt belt.

Spotlight

Nature’s coast guard, with backup

This week, Cropped speaks to the lead author of a new study that looks at how – and where – mangrove restoration can be best supported across the world.

Along Mumbai’s smoggy shoreline, members of the city’s Indigenous Koli community wade through the mangroves at dawn to catch fish. Behind their boats, giant industrial cranes whir to life, building new stretches of snaking coastal highway that blot out the horizon.

Mumbai’s mangrove cover is possibly the highest for any major city. With their tangled, stilt roots, mangrove species serve as a natural defence for a city that experiences storm surges and urban flooding every year. These events disproportionately affect the city’s poor – particularly its fishing communities.

This mangrove buffer is being increasingly threatened, as the city chooses coastal roads and other large development projects over green cover, despite protests. But can green and grey infrastructure coexist to protect vulnerable communities in a warming world? 

A new global-scale assessment published last week tallied the benefits of mangrove restoration for flood risk reduction, factoring in future climate change, development and poverty.

It advanced the idea of “hybrid” coastal defence measures. These combine pairing tropical ecosystems with modern, engineered defences for sea level rise, such as dykes and levees.

When Carbon Brief contacted lead author and climate scientist Dr Timothy Tiggeloven of Vrije Universiteit Amsterdam, he was in Kagoshima in Japan, home to the world’s northernmost mangrove forests. Why combine mangroves and dykes? Tiggeloven explained:

“Mangroves are like active barriers: they reduce incoming energy from waves, but they will not stop the water coming in from storms, because water can flow through the branches. But wave energy can still be overtopped. So if you reduce wave energy via mangroves and have dykes behind this, they very much have a synergy together and we wanted to quantify the benefits for future adaptation.”

According to the study, if mangrove-dyke systems were built along flood-prone coastlines, mangrove restoration could reduce damages by $800m a year, with an overall return-on-investment of up to $125bn.

It could also protect 140,000 people a year from flood risk – and 12 times that number under future climate change and socioeconomic projections, the study said.

According to the study, south-east Asia could reap the “highest absolute benefits” from mangrove restoration under current conditions. Countries that could see the “highest absolute potential risk reduction” – considering future climate damages in 2080 – are Nigeria ($5.6bn), Vietnam ($4.5bn), Indonesia ($4.3 bn), and India ($3.8bn), it estimated.

Maharashtra – which Mumbai serves as the state capital for – is one of two subnational regions globally that could reap the largest benefits of restoration.

Tiggeloven emphasised that the goal of the study was to examine how restoration impacts people, “because if we’re looking only at monetary terms, we’re only looking at large cities with a lot of assets”, he told Carbon Brief.

A pattern that his team found across multiple countries was that people with lower incomes are disproportionately living in flood-prone coastal areas where mangrove restoration is suitable. He elaborated:

“Wealthier areas might have higher absolute damages, but poor communities are more vulnerable, because they lack alternatives to easily relocate or rebuild, so the relative impact on their wellbeing is much greater.”

Poorer rural coastal communities with fewer engineered protections, such as sea walls, could benefit the most from restoration as an adaptive measure, the study found. But as the study’s map showed, there are limits to restoration. Tiggoloven concluded:

“We also should be very careful, because mangroves cannot grow anywhere. We need to think ‘conservation’ – not only ‘restoration’ – so we do not remove existing mangroves and make room for other infrastructure.”

Watch, read, listen

DU-GONE: A feature in the Guardian examined why so many dugongs have gone missing from the shores of Thailand.

WILD LONDON: Sir David Attenborough explored wildlife wonders in his home city of London. The one-off documentary is available in the UK on BBC iPlayer.

GREAT BARRIER: A Vox exclusive photo-feature looked at the “largest collective effort on Earth ever mounted” to protect Australia’s Great Barrier Reef.
‘SURVIVAL OF THE SLOWEST’: A new CBC documentary filmed species – from sloths to seahorses – that “have survived not in spite of their slowness, but because of it”.

New science

• Including carbon emissions from permafrost thaw and fires reduces the remaining carbon budget for limiting warming to 1.5C by 25% | Communications Earth and Environment
• Penguins in Antarctica have radically shifted their breeding seasons in response to rising temperatures | Journal of Animal Ecology
• Increasing per-capita meat consumption by just one kilogram a year is “linked” to a nearly 2% increase in embedded deforestation elsewhere | Environmental Research Letters

In the diary

• 31 January: Deadline for inputs on food systems and climate change for a report by the UN special rapporteur on climate change
• 1 February: Costa Rica elections
• 2-6 February: First session of the plenary of the Intergovernmental Science-Policy Panel on Chemicals, Waste and Pollution | Geneva
• 2-8 February: Twelfth plenary session of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services | Manchester, UK
• 5 February: Future Food Systems Summit | London

Cropped is researched and written by Dr Giuliana Viglione, Aruna Chandrasekhar, Daisy Dunne, Orla Dwyer and Yanine Quiroz. Please send tips and feedback to cropped@carbonbrief.org

Cropped 14 January 2026: Wildfires scorch three continents; EU trade; Food and nature in 2026

Cropped

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14.01.26

Cropped 17 December 2025: ‘Deadly’ Asia floods; Boosting London’s water birds; UN headwinds

Cropped

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17.12.25

Cropped 3 December 2025: Extreme weather in Africa; COP30 roundup; Saudi minister interview

Cropped

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03.12.25

Cropped 19 November 2025: COP30 edition

Cropped

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19.11.25

The post Cropped 28 January 2026: Ocean biodiversity boost; Nature and national security; Mangrove defence appeared first on Carbon Brief.

Cropped 28 January 2026: Ocean biodiversity boost; Nature and national security; Mangrove defence