The Intergovernmental Panel on Climate Change (IPCC) defines a set of scenarios for use by all researchers to standardize climate change modeling globally. Each scenario contains projected emissions values based on potential changes in population size, technology, land use, and energy.
The recommended scenarios from 2000 to 2008 were the Special Report on Emissions Scenarios (SRES). These scenarios were organized into four main categories, and did not account for future efforts to reduce emissions. The four categories are referred to as A1, A2, B1, and B2, and differed in predicted human population growth and economic and technological development.
Since 2008, the IPCC has used Representative Concentration Pathways (RCP) scenarios, which also consist of four pathways. Each RCP is a path of emissions and concentrations over time to be used as a baseline for climate research.
Our research will use the SRES scenarios to predict a "best-case scenario" corresponding to RCP 4.5, a "worst-case scenario" corresponding to RCP 8.5, and an overall mean scenario.