In February 2025, severe flooding in Botswana and South Africa led to 31 fatalities and displaced approximately 5,000 individuals. A study indicated that urbanization and climate change significantly increased the intensity of rainfall events. While enhanced infrastructure and disaster preparedness efforts are underway, variation in climate models complicates precise quantification of climate change impacts on rainfall.
In mid-February 2025, southern Botswana and eastern South Africa experienced heavy rainfall that led to significant flooding, resulting in the tragic loss of 31 lives, including 9 in Gaborone. The floods also displaced around 5,000 individuals and disrupted various services, including the closure of all government schools in Botswana and halted traffic across borders. Emergency services faced challenges reaching stranded residents due to the extensive impact of the floods on infrastructure.
A collaborative study involving scientists from various countries focused on assessing the factors that influenced the intense rainfall in February 2025. They examined the five-day maximum rainfall period in regions significantly affected by flooding. The study highlighted how Gaborone, which is increasingly urbanized, frequently experiences flooding during its rainy season due to overwhelmed drainage systems that cannot accommodate the growing population density.
Analysis suggests that even with a global temperature increase of 1.3 °C, the flooding event observed in February was rare, occurring once every 10 to 200 years. Research indicated that such extreme five-day rainfall events have a return period of approximately 40 years in Gaborone, showcasing a 2-3% chance of occurrence annually. The data also revealed that a colder climate would have seen lower probabilities of this heavy rainfall.
To ascertain the impact of climate change on heavy rainfall, the research compared historical trends with current observations, revealing that significant rainfall events like that of February 2025 would have been much less frequent in cooler climates. The increase in rainfall intensity attributed to climate change was suggested to be around 60% when extrapolated back to a lower temperature.
Contrasting results emerged from climate models, with some indicating increased frequency and intensity of extreme rainfall, while others suggested little to no change. This variability demonstrates that while there is a strong historical trend of increasing rainfall, the exact contribution of climate change remains uncertain. Projections indicate that in a future climate with a 2.6 °C increase, heavy rainfall events are likely to magnify, revealing potential future risks associated with climate change.
The vast majority of the damages incurred in February were attributable to flooding in urban settings, exacerbated by inadequate infrastructure. Historically prevalent flooding became problematic as roads, drainage systems, and health facilities were overwhelmed. Enhancement of urban resilience through improved drainage, regulatory changes, and disaster preparedness is imperative.
Efforts aimed at fortifying flood resilience involve expanding drainage capabilities and enforcing land-use planning, particularly in vulnerable areas. Upgrading infrastructure to mitigate climate-related impacts, integrating hazard assessments into urban development, and establishing robust warning systems will be crucial in preparing for future climatic extremes. These measures represent a holistic approach to addressing flooding and enhancing community resilience against adverse weather events.
The heavy rains in February 2025 in Botswana and South Africa resulted in devastating flooding with significant fatalities and infrastructure damage. While human-induced climate change appears to have intensified the rainfall, quantifying its precise impact remains challenging due to variability in climate models. The flooding underscored the urgent need for improved urban infrastructure and flood resilience measures as urbanization continues to strain existing systems. Ongoing efforts to enhance disaster preparedness and implement strategic land-use policies will be essential in mitigating future risks associated with extreme weather events.
Original Source: www.worldweatherattribution.org
