SA must prepare for unprecedented climate risks, says climatology scientist

Pedestrians hold umbrellas for protection from the sun during a heat wave in New York, US, on Thursday, July 27, 2023. Given that the Northern Hemisphere experienced unprecedented weather this past summer, South Africa should be on high alert this El Niño summer. (Jeenah Moon/Bloomberg via Getty Images)

Humanity is living in the dawn of the era of 1.5°C of global warming that is seeing monthly temperature records being smashed, according to climatology professor Francois Engelbrecht.

This past September was the warmest September on record. It broke the previous record by more than 0.5°C, which is “”exceptional,” said Engelbrecht, the director of the University of the Witwatersrand’s Global Change Institute.

Typically, when a month breaks the long-term record average for that month, it’s usually by 0.1°C, or less. It was “just an immensely hot September”, with June, July and August similarly all breaking monthly temperature records, he said.

“In terms of global warming, we are now starting to see the first days that exceed the 1.5°C threshold. Most days in September had temperatures more than 1.5°C higher than the pre-industrial average temperature for September.”

‘Dawn of a 1.5°C world’

The 2015 Paris Agreement sets out a global framework to stave off the worst effects of climate change by limiting global warming to well below 2°C and pursuing efforts to limit it to 1.5°C — the Earth has seen about 1.2°C of warming.

Last month, the World Meteorological Organisation noted in a statement that a month or year exceeds the 1.5°C limit “does not mean that we have exceeded the 1.5°C level specified in the Paris Agreement because that refers to long-term warming over many years”.

According to Engelbrecht, next year, if the El Niño becomes strong, may be the first year that the average exceeds 1.5°C above the pre-industrial threshold. In 2021, the Intergovernmental Panel on Climate Change said the 1.5°C threshold will be permanently exceeded by the early 2030s.

“There are some studies that are indicating that this may happen already in the late 2020s, so the point is we can no longer prevent the 1.5°C threshold from being reached because there’s just still too much fossil fuel energy in the system,” he explained. 

High alert for South Africa

The global North has witnessed unprecedented heatwaves the past summer, from June to September. “Attribution studies have already indicated to us that climate change has made these heatwaves much more likely to occur in terms of intensity and amplitude. 

He said the deadly Libya flooding in September was caused by a specific storm system made 50 times more likely to occur by climate change. 

More than 100 people perished in the Hawaian fires in August after a very dry period associated with high temperatures and strong winds caused by a hurricane in the vicinity of the islands and “these hurricanes themselves are becoming more intense because of climate change”.

“I think the question we must ask ourselves at the beginning of this summer in the Southern Hemisphere is: we’ve just had a summer in the Northern Hemisphere of unprecedented weather anomalies. Should we not be on high alert in South Africa in terms of this El Niño summer bringing unprecedented weather events to us in our region?”

Intense heatwaves

In January, seven farm workers died during a blistering heatwave in Kakamas in the Northern Cape. The heatwave lasted for about 10 days, with nine days of maximum temperatures above 40°C. Engelbrecht said this was exceptional even for Kakamas. 

“That was during a La Niña season. Now we’re going into an El Niño, which is usually warmer than the La Niña and heatwaves can be devastating during El Niños.”

The strongest heatwaves on record occurred during the 2015-16 El Niño. “I think this summer we will likely see heatwaves more intense than in the summer of 2022-23. And I don’t think anything has changed in terms of the conditions in which our farm workers work in the Northern Cape. 

“It seems to me that often people get appointed into these hard-working outdoor jobs in the sun and heat, people that have comorbidities such as diabetes or being overweight, and such people are even more vulnerable to heat stress in terms of heart attacks and so forth.”

And, for older people living in informal settlements without access to cool water, heatwaves are life-threatening. “Now we have all these issues with Rand Water not being able to pump water to the reservoirs during heatwaves. So they claim that they become overloaded by water demand but they should actually plan and pump much better because it’s exactly during a heatwave that they must supply extra water.”

Engelbrecht is concerned that “despite the lessons we were supposed to have learnt in January 2023” from the farmworkers’ deaths, “we are going into an El Niño with likely even stronger heatwaves and our people will be even more vulnerable because the heatwaves will be even more intense this summer”.

‘Tested like never before’

In the next decade, South Africa should prepare for several unprecedented risks, including drought in combination with extreme heat.

“We are going into the El Niño phase and climate change science tells us that El Niños will become more severe in terms of their impact in Southern Africa. So, when an El Niño strikes it will bring even more intense and more long-lasting heatwaves than in the past … and the droughts may become more intense than previous El Niño droughts.” 

The heat is “extremely dangerous” for people living in informal housing who don’t have air conditioning and cool water. “It’s certain that in the next 10 years we will see heatwaves of unprecedented magnitude in Southern Africa so we’ll be tested like never before in terms of our resilience to heat stress.”

Water security

Such long-lasting droughts are “extremely dangerous” for water security. “If you just look at the winter rainfall region for a start, we’re all now happy after a good rainfall season, quite an exceptional one, the best since 1962, but even with Theewaterskloof and Berg River Dam at maximum capacity, we only have two years of water for the City of Cape Town so we should never be at ease in terms of water security in the winter rainfall region.” 

Climate science is clear. “We will see more winters with below normal rainfall and fewer winters with above normal rainfall in the winter rainfall region. The risk of a Day Zero drought returning to the Cape Town region, to the winter rainfall region, to the Western Cape, is high and for as long as the world continues to warm that type of risk will get larger.” 

With the return of the El Niño, the summer rainfall region, too, is at risk of a Day Zero drought, he said. “We should think more carefully about the possibility of a major multi-year drought occuring in the next 10 to 20 years in the summer rainfall region to the extent that it can bring the level of the Vaal Dam to below 20% because when that happens you can’t pump the water anymore uphill to Gauteng. 

“And, water quality gets so poor you can’t even treat the water to be fit for human consumption anymore … We’ve never faced such a drought before but because of climate change, it’s becoming more likely,” he said, adding that the probability of such a major drought is a research focus at the Global Change Institute.

Flood risks 

Not only are El Niños becoming drier but La Niñas are also becoming wetter. “That means we will also be increasingly challenged by flood risks in eastern Southern Africa so we’ve seen what happened in Durban last year, where 544 people died in an event that was made more intense by climate change.”

Engelbrecht said the biggest risk is tropical cyclones, which are the most devastating flood-producing weather system in the world. “I think we should be extremely concerned … There’s a very good chance that in the next 10 years we will see for the very first time a category 5 hurricane making landfall in Madagascar or Mozambique.”

This has never happened before. He said, the most intense systems we’ve had making landfall in these regions were category 4. “So, I think central Mozambique to northern Mozambique, more or less from Beira northwards, is at risk of such a system and the entire east coast of Madagascar is at risk of such a system making landfall.”

Although this is a clear risk, what is less understood is whether such a system or even a category 3 to 5 can move further southwards than ever before. Engelbrecht said there has never had a category 3 to 5 system hitting as far south as Maputo or Richards Bay. But he thinks it is a possibility because we don’t know exactly what the risk is. He added that this is another area of focus at the Global Change Institute to quantify that risk better.

“We are not prepared at all for such a cyclone. In Beira, people have experience of evacuating from cyclones. It’s not perfect and the Mozambican government regularly evacuates 10 000+ people out of the path of a cyclone. We have zero experience, culture or tradition in evacuating people out of a flood-producing system and that makes us more vulnerable.”

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