The report assesses progress made to mitigate climate change and what options are available for the future. Its findings show that in 2010–2019, global emissions reached their highest level in human history, but it is still possible to at least halve emissions across all sectors by 2030.

‘It’s now or never if we want to limit global warming to 1.5°C,’ said Skea. ‘Without immediate and deep emissions reductions across all sectors, it will be impossible.’

In the scenarios assessed by the IPCC, global greenhouse gas (GHG) emissions must peak before 2025 and be reduced by 43% by 2030. Simultaneously, methane emissions also need to be slashed by a third. Even this would almost certainly exceed 1.5°C of warming temporarily, but it could return to below it by 2100.

The Summary for policymakers of the IPCC Working Group III report, Climate change 2022: Mitigation of climate change was prepared by 278 authors from 65 countries, who reviewed more than 18,000 scientific papers and considered almost 60,000 review comments from governments and experts. It is the third instalment of the IPCC’s Sixth Assessment Report, which will be completed later this year.

The report presents increasing evidence of climate action. Costs of solar and wind energy and batteries have declined by up to 85% since 2010. An increasing number of policies and laws have improved energy efficiency, slashed deforestation rates and stimulated the implementation of renewable energy sources. 

Significant transitions in the energy sector are required to meet the 1.5°C target. This involves a substantial reduction in fossil fossils, broad electrification, greater energy efficiency and the adoption of alternative fuels, according to the IPCC.

The scenarios the IPPC assessed establish that by 2050, global use of coal, oil and gas must drop by about 95%, 60% and 45% respectively compared to 2019 levels, if global warming is to be limited to 1.5°C. 

In industry, responsible for about 25% of global emissions, achieving net zero will require new production processes, low and zero carbon electricity, hydrogen and, in some cases, carbon capture, use and storage (CCUS). It will also necessitate the more efficient use of materials, reusing and recycling products and minimising waste. 

Cities and urban areas have an important role to play by lowering energy consumption through the creation of compact, walkable cities; the electrification of transport in combination with low carbon energy sources; and the restoration and enhancement of nature to absorb and store carbon.

Agriculture, forestry and land use is another important area for large-scale emissions reductions and for the removal and storage of CO₂, say the scientists behind the report. Nature-based solutions can also benefit biodiversity. provide livelihoods and improve food and water security. But, the report emphasises the fact that this should not supersede or delay emissions cuts in other sectors.

In addition, the IPCC highlights policies, infrastructure and technology that can enable lifestyle and behaviour changes for people. These can result in a 40–70% reduction of GHG emissions by 2050. 

Beyond these changes, the report demonstrates that there is sufficient global capital and liquidity to limit warming to below 2°C, although financial flows are currently a factor of three to six times lower than levels needed by 2030. Clear signalling from governments and the international community, involving a stronger alignment between public sector finance and policy, is needed for this to be achieved. 

Hoesung Lee, Chair of the IPCC said: ‘The IPCC report is powerful evidence that we have great potential to mitigate climate change. We are at a crossroads; now is the time for action.’