ENVIRONMENTAL NEWS - The recent extreme weather events in the Southern Cape have raised serious concern among residents, infrastructure managers and environmental practitioners. The Garden Route Environmental Forum's (Gref) convener, Cobus Meiring, asked the Knysna-based climate systems expert, Peter du Toit of FutureClimateIQ, to shed some light on why the Southern Cape increasingly experiences such extreme weather events.
Du Toit said the region's recent experience of intense rainfall, flooding and an unprecedented period of gale-force winds are consistent with evolving atmospheric and oceanic conditions affecting southern Africa.
The Southern Cape sits at the intersection of several dynamic weather systems. The region is influenced by mid-latitude frontal systems moving in from the South Atlantic, as well as moisture-laden air masses driven by warmer ocean temperatures. When these systems interact under unstable atmospheric conditions, they can generate highly concentrated storm events with strong wind fields and intense precipitation over short periods.
One of the key contributing factors highlighted is the increasing variability in large-scale climate drivers, such as the El Niño Southern Oscillation. These oscillations influence rainfall distribution and storm tracks across southern Africa, often intensifying weather extremes when atmospheric conditions align unfavourably.
Du Toit said the recent gale-force wind event, described by local authorities as unprecedented in its sustained intensity and spatial reach, is linked to a deep low-pressure system that intensified rapidly offshore before making landfall along the Southern Cape coastline. This created a strong pressure gradient, resulting in damaging wind speeds across exposed coastal and inland areas.
While these large-scale climate systems are natural, their behaviour is being modified by a warming global climate. Warmer sea surface temperatures increase atmospheric moisture and energy availability, which can enhance storm development and severity.
Local factors
However, Du Toit cautions that climate drivers alone do not fully explain the scale of impacts experienced on the ground. Local factors such as land use change, degraded catchments and invasive alien vegetation significantly amplify run-off, windthrow and infrastructure vulnerability during extreme events.
The combination of these global and local influences is making the Southern Cape increasingly susceptible to high-impact weather events, requiring improved understanding, preparedness and long-term resilience planning.
Gref is a public platform for environmental practitioners and a climate change think tank (grefecsf.co.za).
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