Recent heavy rainfall in Botswana and South Africa led to significant flooding and fatalities. A study by World Weather Attribution indicates such events are more likely due to climate change. Increasing urbanization necessitates improved flood management infrastructure, including an urgent upgrade of stormwater systems and nature-based solutions.
Severe rainfall from February 16-20 caused significant flooding in southern Botswana and eastern South Africa, resulting in over 31 fatalities and affecting approximately 5,500 individuals in Botswana alone. Over 2,000 residents were evacuated due to the deluge, which has been linked to climate change through a study by World Weather Attribution.
The WWA’s research highlights an increasing frequency of extreme five-day rainfall events in the region over recent decades, indicating that current rainfall extremes are approximately 60% more intense due to an average temperature rise of 1.3° Celsius since preindustrial times. However, quantifying the exact impact of human-induced climate change on this event remains challenging, as climate model outcomes vary.
“We haven’t been able to quantify the effect, but as the world is warming, we are seeing more extreme rainfall events like this one,” noted Ben Clarke, a co-author of the study. Joyce Kimutai, another researcher, emphasized the connection between a warming climate and increased rainfall capacity, warning that overwhelmed drainage systems may exacerbate flooding in urban areas.
In Gaborone, Botswana’s capital, there is an urgent need to fortify infrastructure against floods, as highlighted by Piet Kenabatho, a co-author and environmental science professor. He advocates for nature-based solutions, such as enhancing greenery to improve water absorption, given the extensive urbanization that has reduced available green spaces.
However, Kenabatho stresses that improving the stormwater drainage system is critical. Upgrading the aging infrastructure will facilitate faster water evacuation during flooding. He also points to successful managed aquifer recharge schemes in other African nations, which utilize stormwater to replenish underground aquifers, as potential models for flood management improvements in Gaborone.
The recent heavy rainfall in Botswana and South Africa underscores the increasing frequency of extreme weather events tied to climate change and urbanization. While solutions like nature-based infrastructure improvements are essential, significant upgrades to existing drainage systems are crucial to enhance flood resilience in urban environments like Gaborone. Collaborative strategies involving stormwater management can mitigate future flooding challenges.
Original Source: news.mongabay.com
