Impact of Climate Change and Urbanization on Gaborone’s Flooding

In February 2025, southern Botswana and eastern South Africa faced severe flooding due to heavy rainfall, resulting in 31 deaths and displacing 5,000 people. A study evaluated the impact of human-induced climate change on the flooding, indicating increased rainfall intensity due to warming. Infrastructure inadequacies exacerbated the flooding’s effects, underscoring the need for improved urban planning and disaster preparedness to combat future risks.

In mid-February 2025, southern Botswana and eastern South Africa experienced severe flooding due to heavy rainfall, resulting in the loss of at least 31 lives, including 22 in KwaZulu-Natal and nine in Botswana’s capital, Gaborone. This weather event displaced approximately 5,000 individuals, disrupted government services, and caused significant traffic chaos, severely impacting both countries. Emergency services struggled to respond, as many areas became inaccessible.

To investigate the relationship between human-induced climate change and the heavy rainfall that caused these floods, scientists from various countries conducted a comprehensive study. They focused on the rainfall intensity that led to the destruction and assessed whether vulnerability and exposure to climate impacts had intensified due to urbanization and climate conditions.

The study revealed that Gaborone and other urbanized regions frequently endure flooding during the rainy season, primarily due to inadequate drainage systems responsive to escalating population density. The infrastructure of Gaborone has not kept pace with urban growth, rendering low-lying areas particularly at risk during severe weather events.

The 5-day rainfall recorded in February 2025 is classified as a rare occurrence, forecasted to happen only once every 10 to 200 years. Evaluations of weather data indicate that it possesses a 2-3% chance of occurring annually, with a calculated return period of 40 years.

Human-induced climate change is believed to have impacted the intense rainfall event. Analysis of historical data since approximately 1950 suggests that such extreme rainfall events were significantly less likely under cooler climate conditions. It is estimated that the intensity of this rainfall has increased by around 60% due to warming trends.

Different climate models produce varying predictions concerning extreme rainfall frequency. Some indicate increases, while others do not show significant changes, likely due to the interplay between climate change forces and natural variability. Consequently, the exact contribution of climate change to this rainfall event remains challenging to quantify, though evidence suggests the risk of future heavy rain will rise under higher temperature scenarios expected later in the century.

Furthermore, infrastructure inadequacies played a significant role in magnifying the impacts of the flooding; vital systems such as roads and drainage were overwhelmed, causing severe disruptions to health clinics. Efforts are being undertaken to enhance flood resilience through better drainage systems, land-use regulations, and disaster preparedness.

This article highlights the critical impact of climate change and urbanization on the severe flooding experienced in Gaborone and southern Botswana. The findings suggest that while human-induced changes contributed to the rainfall intensity, infrastructure inadequacies intensified the flooding’s effects. It is imperative for urban planning and infrastructure development to incorporate multi-hazard assessments and improve preparedness measures to mitigate future risks. Enhancing drainage and improving zoning laws will be crucial in building resilience against similar extreme weather events in the future.

Original Source: www.worldweatherattribution.org