Since 2010, there have been sustained decreases of up to 85 per cent in the costs of solar and wind energy, and batteries. An increasing range of policies and laws have enhanced energy efficiency, reduced rates of deforestation and accelerated the deployment of renewable energy.
“We are at a crossroads. The decisions we make now can secure a liveable future. We have the tools and know-how required to limit warming,” said IPCC Chair Hoesung Lee. “I am encouraged by climate action being taken in many countries. There are policies, regulations and market instruments that are proving effective. If these are scaled up and applied more widely and equitably, they can support deep emissions reductions and stimulate innovation.”
The Summary for Policymakers of the IPCC Working Group III report “Climate Change 2022: Mitigation of climate change” was approved by 195 member governments of the IPCC on April 4th 2022. It is the third instalment of the IPCC’s Sixth Assessment Report (AR6), which will be completed this year.
According to the report, limiting global warming will require major transitions in the energy sector. This involves a substantial reduction in fossil fuel use, widespread electrification, improved energy efficiency and use of alternative fuels (such as hydrogen).
“Having the right policies, infrastructure and technology in place to enable changes to our lifestyles and behaviour can result in a 40 to70 per cent reduction in greenhouse gas emissions by 2050. This offers significant untapped potential,” said IPCC Working Group III Co-Chair Priyadarshi Shukla.
Cities and other urban areas also offer significant opportunities for emissions reductions, the report says. These can be achieved through lower energy consumption (such as by creating compact, walkable cities), electrification of transport in combination with low-emission energy sources, and enhanced carbon uptake and storage using nature.
Reducing emissions in industry will involve using materials more efficiently, reusing and recycling products and minimising waste. For basic materials, including steel, building materials and chemicals, low- to zero-greenhouse gas production processes are at their pilot to near-commercial stage.
According to the report, this sector accounts for about a quarter of global emissions. Achieving net zero will be challenging and requires new production processes, low and zero emissions electricity, hydrogen and, where necessary, carbon capture and storage.
Agriculture, forestry and other land use can provide large-scale emissions reductions and also remove and store carbon dioxide at scale. However, land cannot compensate for delayed emissions reductions in other sectors. Response options can benefit biodiversity, help us adapt to climate change, and secure livelihoods, food and water, and wood supplies.
The scenarios assessed by IPCC working group III show that limiting warming to around 1.5°C requires global greenhouse gas emissions to peak before 2025 at the latest, and to be reduced by 43 per cent by 2030; at the same time, methane would also need to be reduced by about a third. Even if we do this, it is almost inevitable that we will temporarily exceed this temperature threshold but could return to below it by the end of the century, the scientists say.
The global temperature will stabilise when carbon dioxide emissions reach net zero. For 1.5°C, this means achieving net zero carbon dioxide emissions globally in the early 2050s; for 2°C, it is in the early 2070s.
This assessment shows that limiting warming to around 2°C still requires global greenhouse gas emissions to peak before 2025 at the latest, and to be reduced by a quarter by 2030.
The report looks beyond technologies and demonstrates that while financial flows are a factor of three to six times lower than levels needed by 2030 to limit warming to below 2°C , there is sufficient global capital and liquidity to close investment gaps. However, it relies on clear signalling from governments and the international community, including a stronger alignment of public sector finance and policy.
“Without taking into account the economic benefits of reduced adaptation costs or avoided climate impacts, global Gross Domestic Product (GDP) would be just a few percentage points lower in 2050 if we take the actions necessary to limit warming to 2°C or below, compared to maintaining current policies,” said Shukla.
The Summary for Policymakers of the Working Group III contribution to the Sixth Assessment Report (AR6) as well as additional materials and information are available at https://www.ipcc.ch/report/ar6/wg3/