Carbon budgets have recently received increasing attention in the climate policy arena. Not only are they part of the headline statements of the most recent assessment of the Intergovernmental Panel on Climate Change (IPCC), they have also been proposed as guidance for long-term emission reduction goals within the international climate negotiations under the United Nations Framework Convention on Climate Change (UNFCCC). For example, directly following from the concept of a carbon budget is that as soon as 2055 to 2070, global net emissions of CO2 will have to be phased-out to zero in order to stay below 2°C warming with a likely chance.
A thorough understanding of the interplay between policy choices and the amount of carbon emissions compatible with specific temperature limits gains therefore in importance, in particular because the amount of future carbon emissions compatible with limiting warming to below the 1.5 or 2°C thresholds is vanishing quickly with time.
Mitigation costs are related to the size of the carbon budget and can increase
significantly with a delay of strong decarbonisation, as weaker reduction ambition early on comes with the necessity of much stronger reduction rates later.
Climate Analytics’ Dr. Michiel Schaeffer and Dr. Joeri Rogelj (IIASA) provide key insights that link the theoretical concept of carbon budgets to a real world context, by quantifying policy-relevant emission-scenario aspects that increase or decrease cumulative carbon emissions compatible with limiting warming to below specific temperature limits, like 1.5 or 2°C relative to preindustrial. To achieve this, they explore dimensions not previously assessed by the IPCC.
Our Common Future under Climate Change is the largest conference of the scientific community ahead of the climate summit COP21 in Paris in December. 2000 scientists will meet to address key issues concerning climate change in the broader context of global change and to discuss solutions for both mitigation and adaptation issues.