IPCC Sixth Assessment Report – Working Group III: Mitigation of Climate Change

On 4 April 2022, the Intergovernmental Panel on Climate Change (IPCC) released the third part of its 2022 Sixth Assessment Report (AR6) titled “Climate Change 2022: Mitigation of Climate Change”, following the first two contributions on the physical science basis (August 2021) and on impacts, adaptation and vulnerability (February 2022, see also our blog post here). 

The Working Group III contribution assesses various mitigation pathways based on current national reduction measures and developments. It closely examines the sources of greenhouse gas (GHG) emissions and explores the potential of different sectors as well as climate governance to advance climate protection. Its broad and detailed analysis of mitigation options for the first time also addresses the social aspects of mitigation.

On a positive note, the Report shows that climate protection has found its way onto the political agenda of many States, e.g. through mitigation policies and laws, reduction targets and market instruments. Low-emission technologies have become more cost-efficient and hence globally available due to innovation policy packages.

Notwithstanding this progress, the IPCC however makes clear that immediate and comprehensive structural changes are needed in order to halt global warming. Average annual GHG emissions have reached a new high in the last decade and existing mitigation policies will not suffice to limit warming to 1.5 degrees Celsius. Rather, reaching the 1.5 or 2 degrees Celsius target requires rapid, deep and sustainable emission reductions across all sectors.

While the Report stresses that the time to act is now, as this decade will be decisive, it simultaneously demonstrates that action is both feasible and affordable. There are mitigation options available in every sector across all regions that can halve emissions by 2030. Possible mitigation measures include transitioning to net-zero CO2 energy systems, increasing resource efficiency, infrastructure development, demand-side management, as well as carbon dioxide removal methods. Accelerated and equitable climate action can furthermore be conducive to sustainable development.

In its final section, the Report explains how institutions, governance and socio-cultural factors influence mitigation policies by providing frameworks through which diverse actors interact. Here, the Report also addresses the role of climate litigation. It notes a growing number of climate-related cases and, by reference to high agreement in academia, recognizes their potential to affect the outcome and ambition of climate governance. Cases appear either in the form of systemic climate litigation, through which claimants aim for more ambitious governmental action against climate change, or they challenge state authorization of high-emitting projects. Also, private corporations and financial institutions are being sued for their direct or indirect contribution to global GHG emissions. More and more cases are based on human rights claims with courts showing increasing receptivity towards such arguments. The IPCC takes this trend into account in the context of structural factors shaping climate governance. To what extent litigation actually results in new climate regulations and policies requires further investigation.

Written by Violetta Sefkow-Werner (Research Assistant at the Chair of Professor Helen Keller, University of Zurich)