SRES

Sres, short for Special Report on Emissions Scenarios, is a set of climate change scenarios published by the Intergovernmental Panel on Climate Change (IPCC) in 2000 as part of its assessment work. It provides a framework for projecting future greenhouse gas emissions and the socio-economic developments that drive them, without assuming specific climate policies.

Development and structure: The SRES was produced by IPCC Working Group III for the Third Assessment Report cycle. It defines four narrative scenario families—A1, A2, B1, and B2—each describing different pathways of population growth, economic development, technology change, and energy use. Within the A1 family there are subgroups such as A1FI (fossil fuel intensive), A1T (non-fossil energy), and A1B (balanced across energy sources). A2 envisions higher population growth and more regionalized development, while B1 emphasizes global cooperation and a shift toward cleaner technologies, and B2 combines local solutions with an emphasis on environmental sustainability.

Impact and usage: SRES has been widely used in climate modeling and policy analysis since its publication, shaping many emission trajectories and climate projections employed in early 2000s assessments. It remained a standard reference through much of the 2000s, before increasingly being complemented or replaced in IPCC work by newer approaches.

Limitations and critique: Critics note that SRES-based projections do not incorporate explicit policy responses or probabilistic uncertainty in a single forecast, and that some underlying assumptions about globalization, technology, and energy markets may not reflect real-world developments. As a result, later IPCC work moved toward alternative methods for constructing scenarios.

Legacy: Although superseded in IPCC assessments by newer frameworks such as the Representative Concentration Pathways, SRES remains a foundational, historical reference for understanding how scenario methodologies evolved in climate research.