In Mpumalanga and Limpopo, the floods killed at least 38 people. The Kruger National Park was forced to close. (SANParks)
Human-driven climate change, compounded by a La Niña weather pattern, fuelled the exceptionally intense rainfall that triggered catastrophic flooding in South Africa, Mozambique, Zimbabwe and Eswatini in recent weeks, new research has found.
The rapid attribution analysis by World Weather Attribution shows that the intensity of heavy downpours in the region has increased by about 40% since pre-industrial times, with some areas receiving more than a year’s worth in just days.
Reports suggest as many as 200 people were killed and hundreds of thousands more affected. Vast farming areas were destroyed, deepening food insecurity while damage to roads, homes and public services left many cut off from healthcare, clean water and livelihoods.
In Mpumalanga and Limpopo, the floods killed at least 38 people. The Kruger National Park was forced to close. Minister of Forestry, Fisheries and the Environment Willie Aucamp warned of losses of at least R500 million.
“Human-caused climate change is supercharging rainfall events like this, with devastating impacts for those in its path,” Izidine Pinto, a senior climate researcher at the KNMI Royal Netherlands Meteorological Institute, said in a statement.
“Our analysis clearly shows that our continued burning of fossil fuels is not only increasing the intensity of extreme rainfall, but turning events that would have happened anyway into something much more severe.”
To estimate if human-induced climate change influenced heavy rainfall over the region, the team of authors first determined if there was a trend in observations in the heaviest 10-day rainfall.
“Although this event has an estimated return period of about 50 years and remains rare in today’s climate, which has warmed by 1.3 °C, it would have been much rarer in a climate 1.3°C cooler,” the study said.
In addition to long-term warming, climate variability linked to the El Niño–Southern Oscillation (Enso) played a significant role.
The region, they noted, experienced a weak La Niña during the December to February rainy season, which the researchers estimate made such extreme 10-day rainfall about five times more likely and increased rainfall intensity by roughly 22%.
“Thus, the effect of La Niña is about half the effect of global warming.”
To assess to what extent the observed change can be attributed to human-induced climate change, the scientists typically combine the observations with climate models. However, the models have limitations in this region and do not adequately capture the Enso correlation.
“As a result, we cannot confidently attribute the magnitude of the observed change to climate change,” the authors said.
“However, we have confidence that climate change has increased both the likelihood and the intensity of the 10-day rainfall, based on the observed signal, physical understanding and existing literature.”
How it happened
From late December 2025, exceptionally heavy rainfall triggered widespread flooding across Mozambique, Zimbabwe, South Africa and Eswatini.
Mozambique was hit first, affecting more than 75 000 people, followed by record-breaking rainfall in southern Zimbabwe, north-eastern South Africa and southern Mozambique. Some areas of Limpopo received nearly 945mm over the event period — far exceeding annual averages. Rivers exceeded alert levels, especially in Mozambique, where upstream dam releases worsened flooding.
The analysis details how the flooding caused extensive socio-economic losses, especially in Mozambique, where more than 600 000 people had been affected by 21 January — a figure expected to rise as rains persist.
At least 18 deaths were reported, with more than 70 000 homes damaged or destroyed, health facilities and schools inundated and roughly 5 000km of roads affected, including sections of the country’s main national route, cutting off Gaza province.
More than 105 000 hectares of land and 34 000 livestock were lost, devastating household livelihoods in areas weakened by an El Niño–induced drought in the previous rainy season.
The 2026 floods, the study said, were the third major event in less than 30 years, following the 2000 and 2013 floods in Mozambique, which caused hundreds of deaths and displaced hundreds of thousands.
The study said the Intergovernmental Panel on Climate Change’s sixth assessment report noted an intensification of heavy rainfall in the region, “though with low confidence in attributing this to human influence at the time”.
“Since then, multiple studies have linked climate change to increasingly intense rainfall events, including Cyclone Ana (2022) and heavy rains in eastern South Africa (2022) and Botswana/South Africa (2025), even where models fail to fully capture the trends.
“The growing consistency of extreme rainfall across subregions, seasons and durations suggests higher confidence than previously that climate change is influencing these events. However, researchers caution that further study is needed to disentangle the multiple drivers and accurately quantify the human contribution to unique events such as the 2026 floods.”
Deep vulnerability
The researchers detailed how the disaster exposed deep and persistent social vulnerability in the region.
Rapid urbanisation, inadequate spatial planning and the failure of local governments to provide basic services had left large numbers of people living in informal settlements exposed to flooding.
Poor housing quality, ageing and poorly maintained infrastructure and the degradation of ecosystems that once provided natural flood protection, had further increased risk.
In rural areas, especially in the lower Limpopo River basin, recurrent flooding and other climate hazards had trapped communities in cycles of poverty. Historical mining practices, weak environmental regulation and limited awareness of long-term impacts had entrenched severe damage to aquatic ecosystems, compounding flood exposure when extreme rainfall occurred, the authors said.
Flooding also disrupted critical health systems across the region. Clinics were cut off, medical infrastructure damaged and cold-chain systems for medicines interrupted. Drinking water quality deteriorated while food supplies were lost as crops were destroyed.
When floodwaters destroyed medical infrastructure and blocked access to clinics, the consequences for people living in the communities lasted long after the water receded, said Renate Meyer, a technical adviser on climate and conflict at the Red Cross Red Crescent Climate Centre.
“As we continue to move into a climate that is growing ever more volatile, greater investment in community-led preparedness, strengthening trans-national early warning systems and flood-resilient infrastructure is needed to better protect people from future extremes,” Meyer said.
The impacts are especially severe for vulnerable groups. Elderly people, people living with disabilities and people living with HIV face heightened risks when floods damage health facilities and cut off access to treatment, disrupting essential HIV and TB care and leading to long-term health consequences that extend well beyond the flood event.
The authors warned that pre-existing food insecurity, driven by droughts and other climate shocks, was expected to worsen sharply as floods hit highly exposed agricultural communities in Mozambique and Eswatini.
The Kruger National Park, has emerged as what Aucamp describes as a growing “natural disaster nodal point” due to the convergence of hydrological networks, dense tourism infrastructure and transboundary climatic influences.
The analysis said that while flood policies did exist across the region, they were unevenly implemented. Resource constraints, rapid urban expansion and gaps in community-level preparedness continued to limit their effectiveness.
The researchers argued that reducing future risk would require fully operationalising policies, improving coordination across shared river basins, investing in local infrastructure and early warning systems and strengthening community capacity to prepare for, respond to and recover from floods.
The study, too, highlighted the growing danger of compound and cascading climate hazards. Severe droughts followed by intense rainfall or flooding left communities with little capacity to absorb shocks or recover.
Disrupted livelihoods, damaged homes and reduced access to healthcare could, in turn, trigger disease outbreaks, system failures and further displacement, deepening inequality.
Ultimately, the team of authors concluded that all drivers of risk — the hazard itself, exposure and vulnerability — had intensified in recent years.
Addressing that would require both adaptation and mitigation: reducing vulnerability through resilient infrastructure and ecosystem restoration, while accelerating a just transition away from fossil fuels to limit further warming.