Important Note about Scenario Data

This site includes a range of scenario data taken from or based on several different IPCC reports. It is important to recognize that these scenarios are not probabilistic predictions or forecasts of future changes in population, economic development, greenhouse gas emissions, or climate. The SRES report states:

"Scenarios are alternative images of how the future might unfold and are an appropriate tool with which to analyze how driving forces may influence future emission outcomes and to assess the associated uncertainties. They assist in climate change analysis, including climate modeling and the assessment of impacts, adaptation, and mitigation. The possibility that any single emissions path will occur as described in scenarios is highly uncertain." (IPCC, 2000: 3)

The socioeconomic scenarios available from the IPCC DDC were developed through extensive modeling, analysis, and review by research teams from around the world (IPCC, 2000). In general, these scenarios should reflect plausible, internally consistent future paths based on the best available information and baseline data at the time they were prepared. However, users of these data should pay particular attention to the scenario assumptions, limitations, and initial conditions described in the associated reports and papers. They should also be aware that these socioeconomic scenarios and resultant climate change scenarios may not capture the full range of plausible futures and may incorporate data and assumptions that are not consistent with more recent trends and scientific understanding.

Users should also note that the "downscaled" country-level population and Gross Domestic Product (GDP) data developed by CIESIN represent an initial effort to meet the needs of impacts researchers for country-level data. This work was done independently of the SRES report and has not been endorsed by the IPCC Task Group on Data and Scenario Support for Impacts and Climate Analysis (TGICA).


Gaffin, S.R., C.R. Rosenzweig, X. Xing, and G. Yetman. 2004. Downscaling and Geo-spatial Gridding of Socio-Economic Projections from the IPCC Special Report on Emissions Scenarios (SRES). Global Environmental Change 14(2):105-23. Available at: (a subscription to ScienceDirect may be required to access this paper online)

IPCC (Intergovernmental Panel on Climate Change), 2000. Special Report on Emissions Scenarios. Cambridge: Cambridge University Press. 599 pp. Available at: