SA municipalities get high-resolution data to tackle climate hazards

South Africa’s municipalities are on the frontline of climate change — facing heatwaves, floods and droughts that are intensifying in a rapidly warming world.

Yet, until now, local governments have lacked credible, policy-relevant climate science to inform responses at sub-national level.

This gap has spurred the launch of innovative climate change fact sheets, co-developed by the University of the Witwatersrand’s Global Change Institute (GCI) and the South African National Biodiversity Institute (Sanbi).

Developed for all nine provinces and each of the 44 district municipalities, they translate complex science into practical, locally-relevant information for municipal decision-makers.

“These sub-national fact sheets can be used to understand how climate hazards such as extreme rainfall and oppressive temperatures will affect South Africa in a warmer world,” said the GCI and Sanbi.

“They provide overviews of observed and projected changes in rainfall and temperature at provincial and district levels. By distilling multiple lines of evidence, they offer actionable messages for adaptation at smaller spatial scales.”

The fact sheets are unique in the South African context, offering high-resolution climate information at a district level and “providing sub-national actors with accessible, credible science to guide climate adaptation planning and implementation.

“Once contextualised to the vulnerabilities and exposures unique to each province and district municipality, they become valuable tools for the climate adaptation actions the country urgently needs.”

IPCC-style assessments

Municipal managers face a myriad challenges, said Francois Engelbrecht, director of the GCI and holder of the Wits-Nedbank Chair in Climate Modelling.

“They need to make sense of climate information to understand climate risk in their municipalities. One aspect of risk is the increase in the frequency of climate hazards such as droughts, floods and heatwaves.”

He said the most recent information on climate change in Southern Africa is embedded in the Intergovernmental Panel on Climate Change’s sixth assessment report (AR6), which draws on global and regional projections, observed trends and peer-reviewed literature.

Inspired by the AR6’s regional fact sheets, the GCI developed its own “IPCC-style” assessments at provincial and district scales, with close collaboration among stakeholders.

They include a cover sheet explaining the physical science base: global and regional projections, observed trends, peer-reviewed literature, IPCC-style confidence assessments and the importance of local context. They also explain the IPCC confidence language.

“If we say it is likely that multi-year droughts will occur more frequently in Mopane District over the next 20 years, that means a 66% chance or higher,” Engelbrecht said.

“If we say it is virtually certain that we will have more heatwave days in Northern Cape districts, that means almost a 100% chance. The fact sheets are self-contained and consistent; all terminologies are explained in the cover sheet.”

Like AR6, the fact sheets present projections of rainfall, temperature, very hot days (above 35°C) and extreme rainfall events (≥20mm/day) across near-term (2021–2040), mid-term (2041–2060) and far-future (2081–2099) periods, relative to 1981–2000, with confidence assessments following IPCC methodology.

The GCI and Sanbi said the use of the fact sheets — which were validated through consultations with national, provincial and local government, public entities, research organisations, civil society and independent experts — must be contextualised through

risk assessments considering demographics, socio-economic conditions, governance and local environments.

Engelbrecht said the fact sheets are published online and the underpinning data is freely available.

Links, he added, are to be pursued with other initiatives focused on risk and vulnerability analysis, such as the department of forestry, fisheries and the environment’s adaptation scenarios, the Green Book and the South African Risk and Vulnerability Atlas.

A region on the edge

Southern Africa is one of the world’s climate change hotspots, the cover sheet noted. It is a water-stressed region, which is projected to become drastically warmer and drier.

When water-stressed regions become drier and warmer, the impacts of climate change are felt more severely and options for adaptation in communities and sectors that are vulnerable to climate change are limited.

“In South Africa there is clear statistical evidence of increases in ‘warm extremes’, such as heatwaves and high fire-danger days, over the last few decades. There is some evidence of decreases in annual average precipitation across the region. At the same time, the more frequent occurrence of extreme rainfall events has been detected across most of eastern and central South Africa.”

The devastating flooding in Durban in April 2022 and the severe southern African drought of the summer of 2023-24 are examples of extreme weather events made worse by climate change.

“Their severe impacts were clear reminders of the need for anticipatory planning for climate change impacts. This planning should be based on credible and policy-relevant climate science.”

Climate science is often not easily accessible, especially not in sufficient detail, to inform adaptation responses at a sub-national and local levels, it said.

The sub-national climate change fact sheets present an overview of observed historical and projected future changes in rainfall and temperature and their extremes, at provincial and district municipality level. They are intended to be a first foundational step in adaptation planning processes in the country.

“It is anticipated that more detailed assessments, such as risk and vulnerability analyses, can be undertaken to enhance effective climate change risk reduction and adaptation, thus informing policy and supporting the implementation of the Climate Change Act.”

Origins of the project

Sanbi is a direct access entity of the Green Climate Fund and the Adaptation Fund, explained Mandy Barnett, its chief director for climate change and adaptation finance.

“We have been developing climate change projects for these funds and they always ask, ‘What is the climate science that underpins what you are doing?’”

She recounted the challenge of accessing usable science. “Every time we had to do that, it was a story. We had to make friends with climate scientists; we didn’t always understand the right questions to ask.

“When the Durban floods happened, the team we were working with told us categorically it had nothing to do with climate change. We wanted to be science-driven in our responses, but we struggled to find science that was accessible in a way that users could simply use.

“We embarked on a conversation with Wits University; we had some funding support from the Government of Flanders to help us. And in the conversation, Francois said, ‘Well, why don’t we develop IPCC-style sub-national climate change fact sheets?’” That triggered the process.

“The process ran for a number of years, we had a lot of stakeholders supporting us … This is the beginning of the process. We’ve been told by many of the social scientists that we work with that being able to empower people to use the fact sheets is the next step, that simply having them is not enough.

“But it really is a big step. When we started working with stakeholders, we asked what science people use to determine their climate change responses. Many said they don’t use any science; they just do climate change responses. Of course, that’s a little alarming because how do you know you’re not maladapting if you don’t have the science underpinning what you’re doing?”

‘Living tool’

The fact sheets will become “living tools” that are updated and embedded in municipal decision-making, said Dorah Marema, the head of municipal sustainability at the South African Local Government Association.

“The launch of these fact sheets is something we’ve been waiting for,” she said, citing the flooding in the Eastern Cape that claimed more than 100 lives in June.

“These are not isolated events; they are symptoms of a changing climate that is increasingly impacting our municipalities, especially the most vulnerable ones, the smaller ones. Local government is on the frontline of all these climate impacts.”

Local government is “where policy collides with service delivery, infrastructure backlogs and everything that we can think of”, she said.

“Municipalities are first responders in disasters, bearing the brunt and finding rapid solutions. Yet there is often a lack of capacity and localised data to guide planning.”

“That’s why we strongly support the development and dissemination of these fact sheets, which will empower municipalities with credible district-level climate science to inform their adaptation plans.

Building climate resilience requires inclusive, integrated planning, Marema said. “We are working to mainstream climate resilience across all municipal functions — water, waste, energy, disaster management.

Community engagement, early-warning systems and community-based solutions are essential, including women, youth and vulnerable populations in informal settlements.

“Climate change adaptation is not a choice — it is crucial. We commend Sanbi, Wits and partners for translating science into accessible local data that municipalities can use.”