Climatologists have issued dire warnings about the impact of rising global temperatures on southern Africa, which is becoming increasingly hotter and drier.
First published in the Daily Maverick 168 weekly newspaper.
Gauteng is increasingly likely to experience a “Day Zero” in the next 10 years – but the taps running dry in the economic heartland is not the only major risk that South Africa faces as the planet’s temperature rises.
A recent assessment by climatologists at the Global Change Institute (GCI) at the University of the Witwatersrand indicates an increasing likelihood that the taps in Gauteng are going to run dry sometime in the 2030s or the 2040s if global heating continues unabated.
But water scarcity is not the only risk. Food security is in danger, with the collapse of the maize and cattle industry brought on by drought, the formation of tropical cyclones in Richards Bay, as experienced in Mozambique, and severe heatwaves that could kill many are also predicted by local climatologists.
All three of the Cape provinces are already caught in the grip of the worst drought in a century, the severity and magnitude of which has deemed it worthy of classification as a national disaster.
Now, climatologists say Gauteng too may face a situation much like that faced by Cape Town in 2018, when the taps were 90 days from being turned off.
The assessment by the scientists at the GCI is consistent with the recent Working Group 1 report of the Intergovernmental Panel on Climate Change (IPCC). It shows that the combination of accelerated drying and warming trends across the southern African region is increasing the potential of acute water shortages for millions of people, which will set off a cascade of devastating events pummelling human health and security.
Professor Francois Engelbrecht, Professor of Climatology at the Wits Global Change Institute and a lead author on that recent Working Group 1 report of the IPCC, told DM168 that: “I think that the single biggest risk we are facing because of climate change in the immediate future – by that I mean the next 10 years – is a Day Zero drought in Gauteng.”
The recent IPCC report states, among other things, that droughts will become more frequent at 1.5°C of global warming, and increase proportionately thereafter.
The IPCC has previously identified the 1.5°C global average temperature increase as a tipping point in the climate crisis. It says that, after reaching this tipping point, we can expect “warming of extreme temperatures … frequency, intensity and/or amount of heavy precipitation … and an increase in intensity or frequency of droughts”.
Engelbrecht’s assessment came just days after Minister of Forestry, Fisheries and the Environment Barbara Creecy, reacting to the release of the IPCC report, said: “Sustaining the global temperature of 1.5ºC by the end of the 21st century will require global-scale negative emissions in the second half of the century…”
Engelbrecht, who specialises in numerical climate model development and regional climate modelling, said “we are so vulnerable because we are naturally a warm and dry, water-stressed country with sporadic drought. Now this region is becoming drastically warmer and generally drier. When a warm and dry region becomes drastically warmer and drier, then the options for adaptation are greatly limited.”
As countries continue to pump greenhouse gases into the atmosphere at an immense scale, steadily increasing the global average temperature, “the circulation in the southern hemisphere changes and what happens is that, in a warmer world, very big high-pressure systems form more frequently and more intensely than in the past in the southern African interior,” he explained.
These increasingly frequent and intense high-pressure systems are important in the South African context because of their effects on the already dry country.
“The weather phenomenon that brings rainfall to the interior [of South Africa] is the thunderstorm. Sometimes those are isolated thunderstorms that just occur on a warm day but most of the time they are part of big cloud bands that stretch from the tropics towards southern Africa.
“The problem is if big high-pressure systems form over the interior in the middle of the summer, the first thing they do is to suppress cloud formation so they cause sinking. And when air is sinking, rising air clouds can’t form and thunderstorms can’t form … so they greatly suppress convective rainfall. They also block the formation of cloud bands that connect the tropics to southern Africa.”
And the result, Engelbrecht explained, is that in the summertime “you end up having these long dry spells of sunny weather in the middle of summer when it rains very little. When a summer season has a high frequency of dry spells then it almost always ends up effectively being a drought.
“When you have a drought that lasts five to six years on end, it brings the risk of a potential Day Zero event in Gauteng. The climate science is telling us that we are headed towards a tipping point where that type of scenario becomes more and more realistic for Gauteng.”
The signs are already there. In 2015 and 2016, residents of Johannesburg were told “no irrigation or sprinkler systems” and “no watering of paved surfaces” was allowed. Those water restrictions may now portend an increasingly likely future that goes well beyond suburban inconvenience.
“If the water supply to this province (home to more than a quarter of all South Africans) is compromised it will have substantial economic impacts and it has the potential of leading to social unrest.”
Sunny Morgan, a climate activist with Extinction Rebellion and the African Climate Reality Project, agrees. “South Africans must accept that [we] will be affected negatively by the climate crisis and that we must pull together to solve or at least soften the impacts. The recent episode of violence and looting that we experienced was a microcosm of what may happen if we don’t deal with the inequality in our society. I can link this to the issue of energy and water access because the dissatisfaction in some communities is precisely because of poor service delivery around housing, energy and water. The climate crisis will make this much worse.
“Government, politicians and citizens need to take this very seriously. The vulnerability of Africa to the impacts of climate shocks will exacerbate the inequalities on the ground.
“We saw during Covid how ill-prepared we are, how the Global North hoarded vaccines and withheld vital intellectual property during the crisis. So, project that same behaviour to the climate crisis, multiplied hundredfold in impact and timescale and then you see just how grave the situation is or can become,” said Morgan.
Rand Water for its part says it has embarked on a multipronged strategy to mitigate “challenges posed by climate change”. These include drilling boreholes, reusing effluent water from waste water and acid mine drainage, and reducing water pressure.
Engelbrecht said all the risks facing the country are underpinned by the same projected warming and drying trend in southern Africa.
“Agricultural drought,” he explained, is the second-biggest risk South Africa faces in a warming world.
“There may come a point where the maize crop in southern Africa will no longer be sustainable.
“There exists a risk that the maize crop, our staple food and the cattle industry may completely collapse at 3°C of global warming,” Engelbrecht said.
The global figure of 3°C is equivalent to roughly 6°C of regional warming in southern Africa. The reason for this, Engebrecht explained, is because the same climatic processes that suppress cloud formation in the region allow for more heat and solar radiation to reach the landmass and warm the surface.
When there are clouds, a large portion of the solar radiation is reflected back into space before it can warm the surface, but if there are no clouds all of that sunlight reaches the surface. “And that is why our region is so unique,” he said.
“It’s all about heat tolerance and heat stress in cattle and of the maize plant in certain stages of its growth. It’s that tipping point, as we call it, in terms of the maize crop and cattle industry perhaps existing at even smaller levels of global warming.”
In a joint response to questions from DM168, the team at Life After Coal/Impilo Ngaphandle Kwamalahle – a joint campaign by Earthlife Africa Johannesburg, groundWork and the Centre for Environmental Rights – said: “We need to strategically evaluate and plan for shifts in food production patterns such as this, ensuring that climate-resilient crops replace those that are being displaced by climate change impacts.”
The third risk is the direct impact of heatwaves on human mortality.
“It can happen in South Africa and it has in fact happened. Our data is not so good in terms of detecting mortality induced by heatwaves but let me just remind you of what has happened at the end of June in the Pacific Northwest. Several hundreds of people died during a heatwave that was unprecedented in its intensity. Climate modelling is clear that we can expect unprecedented heatwave events in our own region as global warming continues,” said Engelbrecht.
The point is that northeastern South Africa is, for the first time in recorded history, at risk of a category three to category five hurricane making landfall. The flooding will be enormous. The risk to life will be tremendous for communities living near the rivers in the northeast. We will not be used to 200km/h winds and vulnerable people in informal settlements will have their roofs and walls ripped off.
The New York Times reported that, during the deadly heat wave that blanketed the northwestern parts of the US and Canada in late June, about 600 more people died than would have been typical – three times the affected states’ official estimates of heat-related deaths.
South Africans may be more used to hot weather, but high levels of vulnerability among many South Africans could turn heatwaves deadly. An example is the Garden Route fires of June 2017. These fires occurred after the warmest autumn on record, which dried out the vegetation. They also occurred in the middle of the Cape Town Day Zero drought, where low rainfall for several years had dried the vegetation.
Referring again to the heatwaves in the Pacific Northwest, “in their case, they don’t have air conditioning in their houses simply because they are not used to these types of events. In our case, we don’t have air conditioning because most people can’t afford it.
“So the hard reality is that when a heatwave strikes and you are living in informal housing, you don’t have air conditioning,” Engelbrecht said. “Let’s say you’re an elderly person and you don’t have easy access to cool water, then it is immediately a life-threatening situation. A heatwave means it is not just one day, it is several days of oppressive temperatures and the climate science is very clear that we will see more seasons with increases in the intensity and frequency of heatwaves.”
And then there is the risk of tropical cyclones making landfall in South Africa. “The climate science is clear that as the environment warms, these tropical cyclones can survive further south and that is why this is a risk. South Africa is not prepared for the possibility of an intense tropical cyclone moving southwards where it can maybe impact Maputo and move over the Limpopo River Valley,” said Engelbrecht.
Tropical cyclones seldom make landfall in South Africa. The last recorded case is that of Cyclone Domoina, which in 1984 caused record floods.
“In terms of its intensity, today it would, strictly speaking, not meet the technical category of a category one hurricane yet it was terribly devastating. The point is that these tropical cyclones just don’t reach South Africa but when one did reach us it caused widespread flooding and tens of people died in South Africa,” he said.
Now, because of global warming, there is much more energy available for tropical cyclones to become intense.
“My analysis is, and the assessment of the Global Change Institute is, that the risks exist for such an intense tropical cyclone to make landfall in South Africa. It will bring complete chaos and destruction as we’ve never seen before. We will not know what to do when such a cyclone strikes Richards Bay or if it strikes Maputo and then moves westward along the Limpopo river valley or along the boundary of SA and Zimbabwe.
“The point is that northeastern South Africa is, for the first time in recorded history, at risk of a category three to category five hurricane making landfall. The flooding will be enormous. The risk to life will be tremendous for communities living near the rivers in the northeast. We will not be used to 200km/h winds and vulnerable people in informal settlements will have their roofs and walls ripped off.”
Thandile Chinyavanhu, Climate and Energy Campaigner at Greenpeace Africa, said of the potential of a Day Zero in Gauteng and the other risks that “it is not a difficult scenario to envision at the current rate of emissions. A future characterised by prolonged drought, ecological degradation and cyclones, is not conducive to our health or survival. We are likely to see people succumb to the impacts of these extreme weather events, communicable diseases such as malaria will thrive, and climate shocks will lead to mass job losses across industries such as agriculture, manufacturing, which will erode social justice. We need a just transition away from fossil fuels toward renewable energy now.
“It’s important that South Africans know that the drastic changes in climate we are experiencing are unequivocally linked to human activity and that 70% of the world’s emissions released between 1988 and 2015 were emitted by just 100 companies. Among these carbon majors features South African petro-chemical company, Sasol. South Africa is not a passive actor in this climate crisis but is complicit in enabling the fossil fuel industry’s decimation [of the planet].”
She continued that “South African authorities have the scientific basis to influence their decision-making at COP26; they need to prioritise setting emission reduction targets that are aligned to what is required by science. We cannot afford the luxury of gradualism; we must commit to doing everything in our power, faster and bolder, at all levels, leaving no sector behind.” OBP/DM168
This story first appeared in our weekly Daily Maverick 168 newspaper which is available for R25 at Pick n Pay, Exclusive Books and airport bookstores. For your nearest stockist, please click here.