Latest climate trends and developments

The report begins by analysing recent developments and current climate trends. It confirms that between 2010 and 2019, cumulative global emissions increased, but the rate of growth in global emissions decreased compared to the previous decade. The IPCC estimates that global cumulative greenhouse gas emissions between 2010 and 2019 were around 410 gigatonnes of carbon dioxide or equivalent greenhouse gas. To stay within the IPCC’s ‘carbon budget’ for limiting warming to 1.5C above pre-industrial levels, the world can only emit 500 gigatonnes of CO2 or equivalent greenhouse gases after 2020. In other words, the world burned through the equivalent of 80% of its remaining carbon budget in one decade. This is clearly not a sustainable pattern.

While there have been improvements in energy efficiency and the carbon intensity of energy sources, net emissions have increased across all major sectors globally, though there are still significant regional differences in contribution to greenhouse gas emissions. Both policy measures and technological advancements have avoided emissions that would have otherwise occurred, though the IPCC points to slow and uneven progress on climate finance. Working Group III also concludes that current policies do not align with nationally determined contributions (NDCs), and warming would still likely exceed 1.5C if all NDCs were implemented.

Action required to meet climate targets – three years to peak global emissions

Climate change has long-term consequences but requires immediate action. The IPCC explains that limiting warming to 1.5C will require global emissions to peak before 2025 and that many pathways to 2C of warming will also require this, but this will not happen under current policies. Furthermore, emissions must be almost halved by 2030 to stay within 1.5C, and reduced by a quarter to stay within 2C. Jim Skea, co-chair of Working Group III, asserted that limiting warming to 1.5C would be impossible “without immediate and deep emissions reductions across all sectors”. The table below summarises action required across different sectors to limit warming to 1.5C.

In addition to the solutions outlined above, the IPCC emphasises the importance of demand-side action, including behaviour change, as well as the need for carbon dioxide removal (CDR) measures. The global economic benefit of limiting warming would likely exceed the cost of taking these mitigation measures. The report also confirms a strong link between sustainable development, mitigation of greenhouse gas emissions, and adaptation to climate change.

Ways to strengthen the global response

The IPCC outlines key policy levers and actions that will help achieve the necessary emissions reductions, emphasising that many options are feasible, scalable, and increasingly cost-effective:

• Embedding mitigation efforts within the broader development agenda can accelerate emissions reductions.
• Effective climate governance across multiple policy areas and levels of government through establishing laws, strategies, and institutions can support mitigation efforts.
• Scaling up well-designed regulatory and policy instruments including standards, investment in technology, and carbon pricing mechanisms would help cut emissions, especially when implemented in economy-wide policy packages.
• International cooperation between and within both public and private sector entities will be important for supporting and channelling climate ambition, and international financial cooperation will be vital for increasing climate finance.