Eskom’s Arnot coal-fired power station in Mpumalanga. According to the World Meteorological Organization’s report, CO2 levels in the atmosphere reached record highs in 2024. (Photo: Waldo Swiegers / Bloomberg via Getty Images) 
The World Meteorological Organization (WMO) has warned that the planet is now on track for a further long-term temperature increase. This follows the Geneva-based agency’s release of its Greenhouse Gas Bulletin on Wednesday, 15 October.
According to the report, CO2 levels in the atmosphere reached record highs in 2024, with an annual rise of 3.5 parts per million (ppm), the highest year-to-year increase since systematic measurements began in 1957.
“The heat trapped by CO2 and other greenhouse gases is turbo-charging our climate and leading to more extreme weather. Reducing emissions is therefore essential not just for our climate but also for our economic security and community wellbeing,” WMO deputy secretary-general Ko Barrett said.
Instead of the dramatic emission cuts demanded by the IPCC’s 2018 Special Report on Global Warming, the report shows that the world is moving in the opposite direction. The 2018 report warned that to maintain a chance of keeping global heating below 1.5°C, humanity needed to reduce CO2 emissions by 45% by 2030, relative to 2010 levels. Six years later, those cuts have not materialised – and emissions continue to climb.
Increased carbon dioxide in the atmosphere intensifies the greenhouse effect, leading to amplified human-induced climate change, with devastating consequences for ecosystems, weather patterns and the delicate balance of our planet.
What caused the surge in CO2 levels?
The WMO said the likely reasons for the 3.5 ppm CO2 spike between 2023 and 2024 were large wildfires and reduced CO2 absorption by land and the ocean during the warmest year on record, when global temperatures breached the 1.5°C threshold set in the 2015 Paris Agreement.
/file/dailymaverick/wp-content/uploads/2025/10/ED_497995.jpg "At least nine properties were destroyed or badly damaged by fire in the Sunny Cove area of Fish Hoek on 7 April 2024. (Photo: Gallo Image / Brenton Geach)")
This was further exacerbated by the fact that 2025 was an El Niño year, when the planet is naturally warmer.
Read more: Explainer — El Niño’s impact and what to expect from La Niña
An additional cause for concern for the WMO is the body’s observation that the CO2 absorption rate of carbon sinks (land systems such as the Amazon and the ocean) has also decreased.
The meteorological body said that, in normal circumstances, carbon sinks absorb 50% of the carbon emitted each year; however, as global temperatures rise, the oceans absorb less CO2.
This happens because the greenhouse gas dissolves less effectively in the water when it reaches higher temperatures. At the same time, land absorbs less carbon for myriad reasons, including increased drought.
“There is concern that terrestrial and ocean CO2 sinks are becoming less effective, which will increase the amount of CO2 that stays in the atmosphere, thereby accelerating global warming,” said Oksana Tarasova, a WMO senior scientific officer.
/file/dailymaverick/wp-content/uploads/2025/10/image-12.jpg "Globally averaged CO2 concentration (a) and its growth rate (b) from 1984 to 2024. Increases in successive annual means are shown as the shaded columns in (b). The red line in (a) is the monthly mean with the seasonal variation removed; the blue dots and blue line in (a) depict the monthly averages. Observations from 179 stations were used for this analysis. (Source: World Meteorological Organization)")
/file/dailymaverick/wp-content/uploads/2025/10/image-11.jpg "Increases in successive annual means of atmospheric CO2. (Source: World Meteorological Organization)")
Speaking to Daily Maverick, Professor Francois Engelbrecht, director of the Wits Global Change Institute and Wits-Nedbank Chair in Climate Modelling, echoed that report’s warnings that the record levels of trapped CO2 could result in long-term warmer temperatures.
Read more: Atmospheric CO2 levels now more than 50% higher than in pre-industrial era
“From the late 2020s, every year will be 1.5°C warmer. That means if the emissions continue to increase, then of course, it doesn’t mean we are going to stay at 1.5. We will start to exceed even higher levels,” he said.
Engelbrecht explained that while the 2024 breach is not yet considered a “permanent exceedance” of the 1.5°C threshold (climatologists define permanence as the status holding for a 20-year average), permanence may be reached by the late 2030s.
What does this mean for South Africa?
Engelbrecht highlighted what the increased CO2 levels could mean for South Africa. As director of the Global Change Institute, he and his colleagues have identified five regional tipping points that could reshape life in southern Africa:
Potential ‘Day Zero’ in Gauteng
According to Engelbrecht, increased warming could lead to a “Day Zero” drought in Gauteng. The integrated Vaal River System had historically ensured a reliable water supply, but regional climate models now suggested that future droughts could be so severe that the system might fail. “That is maybe the number-one risk that South Africa faces economically.”
/file/dailymaverick/wp-content/uploads/2025/10/Mohammed-Armani-11-2.jpg "In the early hours of Sunday, 14 July, a devastating fire broke out at the Kenville informal settlement in Durban, destroying more than 200 structures and resulting in the deaths of a pregnant mother and her baby. (Photo: Gift of the Givers)")
Unprecedented heatwaves
The second tipping point involved extreme heat events of unprecedented intensity. These would pose a lethal threat to vulnerable populations, especially the elderly and those living in informal housing without access to cooling. Engelbrecht highlights the public health danger, noting that “if you’re in an informal house, and there’s a heatwave, it is immediately life-threatening”.
Collapse of agriculture
A third potential tipping point could devastate the maize and cattle industries, which form the backbone of southern Africa’s food system. Engelbrecht predicts that beyond 2°C of warming, droughts and heatwaves will become so frequent and severe that farming maize or raising cattle may no longer be viable.
Mass wildlife die-offs
The fourth risk concerned wildlife populations in major reserves such as the Kruger National Park and the Serengeti. Because these ecosystems were fenced, animals couldn’t migrate in search of water or food during severe droughts. Engelbrecht warns of possible “massive die-offs” if climate extremes continue to intensify.
/file/dailymaverick/wp-content/uploads/2024/01/Worcestor-fire-20.jpg "Farmers and farmworkers came together to save their properties from fire near Witelssrivier in Worcestor on 28 January 2024. (Photo: Shelley Christians)")
/file/dailymaverick/wp-content/uploads/2023/12/905A1546.jpg "Firefighters working their way along the firebreak facing the wind in December 2024. (Photo: Gunnar Oberhosel)")
Cyclones moving south
The fifth tipping point involved the potential for category 3-5 tropical cyclones to reach as far south as Durban, a phenomenon not recorded before. As ocean and atmospheric temperatures rise, such extreme storms could become possible, threatening densely populated coastal areas.
What can be done?
Towards the end of the interview, the conversation turned to the most pressing question: Is it too late to reverse course?
Engelbrecht’s answer is both sobering and cautiously hopeful. “It’s too late now to avoid 1.5°C of global warming. But there is still enough time to reduce emissions strongly so that we can avoid the 2°C level.” Avoiding this next threshold, he argues, is essential to prevent even greater loss of life, biodiversity and economic stability. DM