Working Group III of the Intergovernmental Panel on Climate Change is launching the full version of its contribution Climate Change 2014: Mitigation of Climate Change to the IPCC Fifth Assessment Report in its final format. As the UNFCCC Climate Change Conference prepares to open in Lima, Peru, the IPCC is publishing its assessment of the relevant options for limiting climate change.

The Working Group III contribution to the Fifth Assessment Report explores the solutions involved in climate change mitigation, drawing on experience and expectations for the future. This exploration is based on a comprehensive and transparent assessment of the relevant scientific, technical and socio-economic literature.

The intent of the report is to facilitate an integrated and inclusive deliberation of alternative climate policy goals and the different possible means to achieve them, including technologies, policies, and institutional settings. It informs readers about the costs and benefits, risks and trade-offs of alternative policy options.

Working Group III is led by three Co-Chairs: Ottmar Edenhofer from Germany, Ramón Pichs-Madruga from Cuba, and Youba Sokona from Mali.

“Our role is akin to that of cartographers. We map out different possible pathways for climate change mitigation, assess their practical consequences and trade-offs, and we clearly mark value assumptions and uncertainties,” said Edenhofer.

“We do not recommend any particular policy choices, but we report the policy-relevant information about their requirements, risks and co-benefits. We hope this report will be used like a map for navigating the widely unknown territory of climate policy,” said Sokona.

The close to 1500-page Working Group III report features several new elements. The report contains a new set of 1200 scenarios mapping out pathways to limiting climate change to different levels. These include a whole range of mitigation scenarios with a better than evens chance of keeping temperature rise below 2°C relative to pre-industrial levels. A full chapter is devoted to human settlements and infrastructures. Governance structures for the design of mitigation policies are discussed at the global, regional, national and sub-national level. The report closes with a new chapter about investment needs and finance.

The full version of the Working Group III contribution to the Fifth Assessment Report consists of a Summary for Policymakers, a more extensive Technical Summary, 16 chapters including more than 250 high-resolution graphics, frequently asked questions for each chapter and 6 Annexes.

“The assessment process is a very ambitious scientific undertaking, involving hundreds of experts from around the world and thousands of relevant publications. To make it fully transparent and accountable, we are also publishing the drafts of the report, the comments we have received and the responses our authors provided,” said Pichs-Madruga.

In the review process, Working Group III received more than 38,000 comments from expert reviewers and governments.

According to the assessment it is possible, using a wide array of technological measures and changes in behaviour, to limit the increase in global mean temperature to 2ºC above pre-industrial levels. However, only major institutional and technological change will give a better than evens chance that global warming will not exceed this threshold agreed by governments. Delays in reducing emissions and limited availability of technologies will increase mitigation challenges.

The report, entitled Climate Change 2014: Mitigation of Climate Change, is the third of three Working Group reports, which, along with the Synthesis Report released in October 2014, constitute the IPCC’s Fifth Assessment Report on climate change. The Working Group III Summary for Policymakers, full report and further information are available at www.mitigation2014.org or www.ipcc.ch.