The Emission Scenarios of the IPCC Special Report on Emission Scenarios (SRES)A1. The A1 storyline and scenario family describes a future world of very rapid economic growth, global population that peaks in mid-century and declines thereafter, and the rapid introduction of new and more efficient technologies. Major underlying themes are convergence among regions, capacity building and increased cultural and social interactions, with a substantial reduction in regional differences in per capita income. The A1 scenario family develops into three groups that describe alternative directions of technological change in the energy system. The three A1 groups are distinguished by their technological emphasis: fossil intensive (A1FI), non-fossil energy sources (A1T), or a balance across all sources (A1B) (where balanced is defined as not relying too heavily on one particular energy source, on the assumption that similar improvement rates apply to all energy supply and end use technologies). A2. The A2 storyline and scenario family describes a very heterogeneous world. The underlying theme is self reliance and preservation of local identities. Fertility patterns across regions converge very slowly, which results in continuously increasing population. Economic development is primarily regionally oriented and per capita economic growth and technological change more fragmented and slower than other storylines. B1. The B1 storyline and scenario family describes a convergent world with the same global population, that peaks in mid-century and declines thereafter, as in the A1 storyline, but with rapid change in economic structures toward a service and information economy, with reductions in material intensity and the introduction of clean and resource efficient technologies. The emphasis is on global solutions to economic, social and environmental sustainability, including improved equity, but without additional climate initiatives. B2. The B2 storyline and scenario family describes a world in which the emphasis is on local solutions to economic, social and environmental sustainability. It is a world with continuously increasing global population, at a rate lower than A2, intermediate levels of economic development, and less rapid and more diverse technological change than in the B1 and A1 storylines. While the scenario is also oriented towards environmental protection and social equity, it focuses on local and regional levels. An illustrative scenario was chosen for each of the six scenario groups A1B, A1FI, A1T, A2, B1 and B2. All should be considered equally sound. The SRES scenarios do not include additional climate initiatives, which means that no scenarios are included that explicitly assume implementation of the United Nations Framework Convention on Climate Change or the emissions targets of the Kyoto Protocol. Emission scenarios are not assessed in this Working Group One report of the IPCC. This box summarizing the SRES scenarios is taken fromthe TAR and has been subject to prior line by line approval by the Panel. Source & © IPCC Climate Change 2007: Related publication:
Other Figures & Tables on this publication: Figure SPM-1. (WGI) Changes in Greenhouse Gases from Ice-core and Modern Data Figure SPM-2. (WGI) Radiative Forcing Components Figure SPM-3. (WGI) Changes in Temperatures, Sea Level and Snow Cover between 1850 and 2010 Figure SPM-4. (WGI) Global and Continental Temperature Change Figure SPM-5. (WGI) Multi-model Averages and Assessed Ranges for Surface Warming Figure SPM-6. (WGI) AOGCM Projections of Surface Temperatures Figure SPM-7. (WGI) Projected Patterns of Precipitation Changes Figure SPM-1. (WGII) Changes in physical and biological systems and surface temperature 1970-2004 Figure SPM-2. (WGII) Key impacts as a function of increasing global average temperature change Figure SPM-1. (WGIII) Emissions of different greenhouse gases 1970-2004 Figure SPM-3a. (WGIII) Distribution of regional per capita greenhouse gas emissions Figure SPM-3b. (WGIII) Distribution of regional greenhouse gas emissions per unit of income Figure SPM-4. (WGIII) Global greenhouse gas emissions for 2000, 2030 and 2100 Figure SPM-5a/5b. (WGIII) Estimated global economic mitigation potential Figure SPM-6. (WGIII) Estimated economic mitigation potential in 2030 as a function of carbon price Global greenhouse gas emissions 1970-2004 Table SPM-5. (WGIII) Characteristics of post-TAR stabilization scenarios [Table TS 2, 3.10]a Table SPM-1. (WGIII) Global economic mitigation potential in 2030 estimated from bottom-up studies. Table SPM-2. (WGIII) Global economic mitigation potential in 2030 estimated from top-down studies. Figure SPM-2. (WGII) Key impacts as a function of increasing global average temperature change Figure SPM-6. (WGIII) Estimated economic mitigation potential in 2030 as a function of carbon price The Emission Scenarios of the IPCC Special Report on Emission Scenarios (SRES) Box SPM-2 (WGIII) Mitigation potential and analytical approaches Box SPM-3 (WGIII) Assumptions in studies on mitigation portfolios and macro-economic costs |