According to the Working Group III contribution to the IPCC’s Fifth Assessment Report, it would be possible, using a wide array of technological measures and changes in behaviour, to limit the increase in global mean temperature to two degrees Celsius above pre-industrial levels.  However, only major institutional and technological change will give a better than even chance that global warming will not exceed this threshold.

The report, entitled Climate Change 2014: Mitigation of Climate Change, is the third of three Working Group reports, which, along with a Synthesis Report due in October 2014, constitute the IPCC’s Fifth Assessment Report on climate change. Working Group III is led by three Co-Chairs: Ottmar Edenhofer from Germany, Ramón Pichs-Madruga from Cuba, and Youba Sokona from Mali.

Since the last IPCC assessment report, published in 2007, a wealth of new knowledge about climate change mitigation has emerged.  The authors of the new, fifth Working Group III report have included about 10,000 references to scientific literature in 16 chapters.

Stabilizing greenhouse gas concentrations in the atmosphere requires emissions reductions from energy production and use, transport, buildings, industry, land use, and human settlements. Mitigation efforts in one sector determine the needs in others.

Cutting emissions from electricity production to near zero is a common feature of ambitious mitigation scenarios.  But using energy efficiently is also important.

“Reducing energy use would give us more flexibility in the choice of low-carbon energy technologies, now and in the future.  It can also increase the cost-effectiveness of mitigation measures,” Pichs-Madruga said.  Since publication of the Fourth Assessment Report there has been a focus on climate policies designed to increase co-benefits and reduce adverse side-effects.

The Working Group III report consists of the Summary for Policymakers released today, a more detailed Technical Summary, the underlying 16 chapters, and three annexes.  Working Group III chapter teams were formed by 235 authors and 38 review editors from 57 countries, and 180 experts provided additional input as contributing authors.  More than 800 experts reviewed drafts of the report and submitted comments.