The Intergovernmental Panel on Climate Change has released the third part of its sixth assessment report.
This report, completed by the global authority on climate change, demonstrates that we are hurtling towards a dangerously warmed world with our current and planned fossil fuel infrastructure.
But the report also makes it clear that decarbonising is not only feasible – it’s necessary.
“Greenhouse gas emissions can be halved by 2030, which is what we need to achieve the Paris goals,” says Professor Tommy Wiedmann, a researcher in sustainability at the University of New South Wales, and a lead author on chapter 2 of the report.
How can they be halved? The IPCC has a list – covering energy, transport, agriculture, industry, negative emissions practices, and much more.
In even better news, this effort will largely be economically and socially better for people around the world – particularly for countries which have contributed the least to global emissions, typically nations with the fewest resources.
“Eradicating extreme poverty, energy poverty, and providing decent living standards to all in these regions in the context of achieving sustainable development objectives, in the near term, can be achieved without significant global emissions growth,” reads the summary for policymakers.
The transition won’t be easy – it demands a lot of work and some upfront costs. But done well, it will improve human health and equality while preventing climate catastrophe.
So: what are the highlights? Read on to find out.
Emissions cuts must be fast, and deep
To remain under 1.5°C, emissions must peak before 2025, and rapidly fall after that. And to stay under 2°C, emissions likewise must fall rapidly once they’ve peaked.
The IPCC characterises this as “deep” cuts to emissions: incremental change is insufficient to prevent warming.
It’s impractical to build new fossil-fuel based power plants or mines.
“Emissions from existing and planned fossil-fuel infrastructure alone are higher than those consistent with limiting warming to 1.5 degrees Celsius,” says Wiedmann.
Emissions growth is slowing, and emissions are actually falling in more than a dozen countries
Globally, greenhouse gas (GHG) emissions are still growing. But the growth is no longer accelerating: they’ve been petering out since 2018, before the pandemic.
But the current declining pace of emissions growth still is insufficient. In this report, the IPCC still states it’s likely we’ll exceed 1.5°C on our current trajectory, and only rapid mitigation will keep us below 2°C.
Around the world, the IPCC marks 18 countries which have sustained emissions reductions for more than a decade, of which some have reduced emissions by over a third. These reductions came from changes in both policy and economic structure.
The report summary for policymakers points out that these cuts “have only partly offset emissions growth”.
Renewable energy is cheaper
The report finds that since 2010 the global cost of solar energy has fallen by 85%, wind energy by 55%, and lithium-ion batteries by 85%.
“The solutions are now economically attractive – they aren’t a matter of completely denying the economy,” says Distinguished Professor Peter Newman, a researcher in sustainability at Curtin University and co-ordinating lead author on the transport chapter of the report.
In many places, including Australia, solar and wind energy are the cheapest sources of power.
Electrification is practical
Along with the plummeting cost, renewable energy can be integrated into an economy pragmatically. As the report points out, shifts to electrification can also improve human health and employment.
Even the transport sector can electrify in a straightforward way, according to Newman.
“It’s quite clear that big trucks and big trains can also use batteries,” he says, citing Rio Tinto’s electric trains in Western Australia’s Pilbara region as a recent example.
Big government policies work
Government policy works best to reduce emissions when it’s part of a nation-wide package – rather than smaller individual decisions.
The report emphasises carbon pricing and technological support as two clear things that reduce emissions but points out that climate policy should be integrated into other things too.
“Economy-wide packages that support mitigation and avoid negative environmental outcomes
include: long-term public spending commitments, pricing reform; and investment in education and
training, natural capital, R&D and infrastructure,” reads the summary.
“We have not had that in Australia,” points out lead author Professor Frank Jotzo, director of the Centre for Climate Economics and Policy at the Australian National University.
But government isn’t the only lever
“Climate action needs to be broad-based across society,” says Jotzo.
“It’s not just a matter for government, but it goes right to the business community. We need engagement by civil society, strong independent institutions – so in Australia’s case, that would be the Climate Change Authority. They all have a role to play,” he adds.
Individual action can play a role, through lifestyle change such as eating less meat and reducing carbon-intensive travel. This can be done in addition to involving your communities, workplaces, and governments in broader climate action.
“The aim should be to take advantage of all options, so changing lifestyles should be part of the package, simply to increase our chances,” says Wiedmann.“The report also outlines the co-benefits, like better health, better wellbeing, et cetera.”
Carbon dioxide removal will help, but not solve, the problem
Negative emissions practices – which include everything from soil carbon farming to direct-air capture of CO2 – are included in the IPCC’s projections to keep climate change under 2°C, alongside rapid and deep emissions cuts.
“Our report has assessed 12 different carbon dioxide removal strategies. And these include a range of processes for removing CO2 from the atmosphere,” says lead author Dr Annette Cowie, a senior principal research scientist in climate policy at the NSW Government Department of Primary Industries, and an adjunct professor at the University of New England.
“Most of those are biological processes relying on photosynthesis that then store carbon in plants and soil.”
These technologies will be crucial in offsetting areas where it’s hard to reduce emissions immediately – such as in steel and concrete-making, and some agricultural emissions. But they won’t be sufficient substitutes for electrifying and transitioning energy systems.
Agriculture and land use plays a big role here, and the IPCC suggests that 20-400 billion tonnes of CO2 removal can be done, and needs to be done, by the agricultural, forestry and land-use sectors.
“The land can host methods that are quite mature, very familiar, like tree planting or building soil carbon, and also the emerging method of biochar,” says Cowie.
“Many of the other carbon dioxide removal strategies are less mature – direct air carbon capture and storage for example, or enhanced weathering.”
Ellen Phiddian is a science journalist at Cosmos. She has a BSc (Honours) in chemistry and science communication, and an MSc in science communication, both from the Australian National University.
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