Risks from droughts to deadly heatwaves

An expert warns South Afrca's climate future is fast becoming hotter, drier and more dangerous

- Sheree Bega

The biggest economic risk South Africa faces from climate change is the possibility of a Gauteng “Day Zero” drought.

This was the stark warning issued by Francois Engelbrecht, director of the Global Change Institute (GCI) at the University of the Witswatersrand and the holder of the Wits-Nedbank chair in climate modelling.

“We are speaking here about a climate-induced drought, not shorter-term water shortages caused by infrastructure issues.

“We are talking about water not being available via the Vaal Dam to reach Gauteng,” he told a webinar at the launch of innovative climate change fact sheets, co-developed by the GCI and the South African National Biodiversity Institute, for all nine provinces and each of the 44 district municipalities.

Such a drought has never occurred before. “Our research is telling us that it is becoming possible, even in the next 10 years, and the risk increases for as long as the world continues to warm.”

Engelbrecht pointed to the devastating 2023-24 summer drought, during which Zambia and Zimbabwe lost more than 70% of their maize crop, with effects also felt on the Vaal Dam.

“Long-lasting, climate-fuelled droughts with devastating heatwaves are a very big risk for us moving forward,” he said.

The biggest question, he said, is whether the Vaal Dam and the Integrated Vaal River System (IVRS) will always remain as reliable as they have been since their construction.

“Can we always count on water from the IVRS in a world where climate change is making droughts worse?”

Unprecedented heatwaves, fenced-in wildlife

The next risk is long-lasting heatwaves combined with extreme drought that could push South Africa past a tipping point where it loses its maize crop and cattle industry, Engelbrecht said.

The Intergovernmental Panel on Climate Change (IPCC) has found that at 3°C of global warming, such a collapse is likely because of heat stress on crops and livestock.