Global greenhouse-gas emissions should have their numbers dwindle if we remain faithful to emerging technologies. Photo: Supplied
The target of limiting global temperature rise to 1.5°C is likely to be breached within the next decade, the Intergovernmental Panel on Climate Change (IPCC), the United Nations’s climate science body, has warned in its latest report.
Climate change is a threat to human well-being and planetary health, it said. “There is a rapidly closing window of opportunity to secure a liveable and sustainable future for all. The choices and actions implemented this decade will have impacts now and for thousands of years.”
Human activities, principally through emissions of greenhouse gases, have “unequivocally” caused global warming, with global surface temperature reaching 1.1°C above 1850 to 1900 in 2011 to 2020, the report said.
“Global greenhouse gas emissions have continued to increase, with unequal historical and ongoing contributions arising from unsustainable energy use, land-use and land-use change, lifestyles and patterns of consumption and production across regions, between and within countries, and among individuals.”
In 2019, the report found that atmospheric carbon dioxide concentrations (410 parts per 22 million) were higher than at any time in at least 2 million years, and concentrations of methane (1 866 parts per billion) and nitrous oxide (332 parts per billion) were higher than at any time in at least 800 000 years.
The IPCC scientists found that there are “multiple, feasible and effective” options to reduce greenhouse gas emissions and adapt to human-caused climate change, which are available now.
Insufficient plans in place
In 2018, the IPCC highlighted the unprecedented scale of the challenge required to keep warming to 1.5°C. “Five years later, that challenge has become even greater because of the continued increase in greenhouse gas emissions. The pace and scale of what has been done so far, and current plans, are insufficient to tackle climate change,” it said.
More than a century of burning fossil fuels, as well as unequal and unsustainable energy and land use, has led to global warming of 1.1°C above pre-industrial levels, causing more frequent and more intense extreme weather events that have led to increasingly dangerous impacts on nature and people in every region of the world.
Restricting warming to 1.5°C will require deep, rapid and sustained greenhouse gas emissions reductions in all sectors. The report warns how, without a strengthening of policies, global warming of 3.2°C is projected by 2100.
‘Fossil fuel highway’
This Synthesis Report of the IPCC Sixth Assessment Report (AR6) summarises the state of knowledge of climate change, its widespread impacts and risks, and climate change mitigation and adaptation. It integrates the main findings of AR6 based on contributions from the three working groups and the three special reports.
Aïda Diongue-Niang, a synthesis report author from Senegal, said the report has highlighted that climate change is a reality in every part of the world, particularly Africa. “The warmer it gets, the worse it gets.”
She said keeping the temperature below 1.5°C is still possible but it needs sustained action, “so the future is in our hands”.
Christopher Trisos, a synthesis report author and the director of the Climate Risk Lab at the African Climate and Development Initiative, used an analogy of humanity speeding down a fossil fuel highway.
“If we think about the science in the report, what it shows globally is that society is still on the fossil fuel highway and we’re in the fast lane and the 1.5°C exit is coming up and we know how to get there but we haven’t pulled into the slow lane yet, we haven’t hit the brakes,” he said.
“If we turn into the 1.5°C offramp on this highway, we get to a neighbourhood that is riskier than today, it will have more losses and damage but, over time, we could learn to survive there, we could learn to thrive there, we could learn to have sustainable development for all if we adapt to climate change and integrate climate change with mitigation, to do things like improve nutrition, health and food security.”
What the report, too, shows is that if humanity misses the 1.5°C exit, “we shouldn’t just keep going all the way” to 4°C. “We can try and get off this highway at 1.6°C or 1.7°C.”
And, all the people in the vehicle have to co-operate to take the earliest exit.
“We need to help each other, work together and share our knowledge, our technology and our resources internationally, especially for the benefit of those who are most vulnerable to climate change,” he said.
Most comprehensive assessment
The report, Trisos said, provides the most comprehensive and best available scientific assessment of climate change.
“The report contains really important warnings for humanity. The first one, which is perhaps not surprising, is the pace and scale of climate action today are insufficient to tackle the climate change threats ahead of us and the ones that we are already experiencing. The second warning and call for action is that we have to have rapid and deep reductions in greenhouse gas emissions and accelerated implementation of adaptation in this decade to secure a sustainable future for all.”
This is not about climate mitigation or adapting to climate change. “We have to do both.”
The negative impacts from human-caused climate change are already here, with the report presenting stronger-than-ever evidence for the loss and damage being experienced by people and ecosystems.
“For example, in all regions, increases in extreme heat events are leading to human mortality and illness from heat. There are also impacts on water scarcity and food security, especially in vulnerable countries in regions like Africa, and small-island states. There are impacts on health and well-being, including on mental health, due to things like trauma from experiencing extreme events such as flooding or heat. There are also impacts in cities and settlements on infrastructure as well as on energy systems.”
In the oceans, coral reefs and seagrasses are being lost and degraded while on land, “we’re seeing mass mortality in trees, for example, in areas such as California, because of extreme heat and drought events”, Trisos said. “On the African continent, we have evidence for changing ecosystem structure because of climate change as well as changes in species distribution — species shifting their geographic ranges towards cooler climates.”
Every increment of warming matters
Extremes become more widespread and pronounced with every increment of warming. “As global warming increases especially above 2°C and towards 4.5°C, for countries in the tropics and many developing countries, there are many days a year, over 100 days in many regions, where the combination of high humidity and high heat could pose a very dangerous risk of potential death for people, for example, working outdoors, or in construction or agriculture.”
In Africa, many people are employed in agriculture and rely on smallholder agriculture for their income and spend a lot of their year outdoors. “So this is a risk we should take very seriously.”
And as global warming intensifies, the risks become more complex and more difficult to manage.
“We can expect to see more frequent and intense combinations of heat and drought that reduce soil moisture and ecosystem health and, at the same time, that can lead to drops in crops and food yield losses,” Trisos explained, adding extreme heat events in marine environments can lead to negative impacts on fish stocks.
Millions of people in parts of the Global South have been exposed to acute food insecurity and reduced water security, partly because of climate change. Many of the largest impacts are being felt in Africa, parts of Asia, Central and South America, small islands and vulnerable communities in the Arctic.
About 3.3 to 3.6 billion people live in contexts that are highly vulnerable to climate change, the report said. “People in highly vulnerable regions such as these are up to 15 times more likely to die in floods, droughts and other extreme events compared to those in other less vulnerable regions such as parts of northern Europe and North America,” Trisos explained. “In the context of Africa, in many cases, people think about droughts affecting the most people but we should not forget that flooding, especially in our urban areas, is a major climate hazard.”
The greatest gains in well-being could come from prioritising climate risk reduction for low-income and marginalised communities, including people living in informal settlements, he said.
Do both
The report is clear that the feasibility and effectiveness of adaptation options decrease as global warming increases. “That is why we have to do both — rapid mitigation and accelerate adaptation action at the same time. Also, as global warming increases, the feasibility of some mitigation options decreases.
For example, nature-based approaches, such as conserving and restoring forests to avoid or reduce greenhouse gas emissions, become less effective as warming increases because they are at risk from heat, drought and fires.
“Ecosystems can help us limit global warming and adapt to climate change, but they have limits. Ecosystems can only help us if we also rapidly cut emissions in all other sectors (transport, electricity generation, industry, agriculture).”
Finance
The IPCC’s report found that public and private finance flows for fossil fuels are still greater than those for climate adaptation and mitigation. “The overwhelming majority of tracked climate finance is directed towards mitigation, but nevertheless falls short of the levels needed to limit warming to below 2°C or to 1.5°C across all sectors and regions.”
Trisos said accelerated climate action would only come about if there is a “many-fold increase in finance. Insufficient and misaligned finance is holding back progress.”
The good news, he said, is that there’s enough global financing to rapidly reduce emissions but financing currently is misaligned, with more public and private sector financing “still going to fossil fuels” compared to renewable and clean energy.
Taking more rapid adaptation and mitigation action can reduce poverty and hunger, improve health and livelihoods and provide not only clean energy but clean water and air.
“Reducing greenhouse gas emissions often also improves local air quality and the costs of mitigation could be more than offset in health benefits, so people living longer, healthier lives because of lower air pollution.”