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Long-Term Scenarios
Due to the long time horizon of global greenhouse gas concentrations in the atmosphere, near-term climate mitigation strategies should be framed in context with long-term climate assessments. EPA has supported and contributed to a variety of efforts to model and analyze long-term scenarios of greenhouse gas concentrations and economic impacts, including the Energy Modeling Forum, the U.S. Global Change Research Program, and the IPCC 4th Assessment Report. The long-term scenarios typically focus on the time frame out to 2100.
- Energy Modeling Forum
- U.S. Global Change Research Program
- IPCC 4th Assessment, Working Group III Report, Mitigation of Climate Change
The Energy Modeling Forum
The Energy Modeling Forum was established by Stanford University to explore energy and environmental issues through the collaboration of diverse modeling teams from around the world. The Energy Modeling Forum, Working Group 21 (EMF-21) focused specifically on multi-gas strategies to address climate change and resulted in the publication of a Special Issue #3 of The Energy Journal, Multi-Greenhouse Gas Mitigation and Climate Policy 
. EPA contributed a number of papers to the special issue. For more information about the Energy Modeling Forum, please visit the EMF-21 Web page . EPA is also participating in a new study, EMF-22, that specifically addresses long-term emissions scenarios.
United States Global Change Research Program
The U.S. Global Change Research Program (USGCRP) integrates federal research on climate and global change, as sponsored by thirteen federal agencies and overseen by the Subcommittee on Global Change Research under the Committee on Environment and Natural Resources, overseen by the Executive Office of the President, and facilitated by an Integration and Coordination Office. The USGCRP began as a presidential initiative in 1989 and was mandated by Congress in the Global Change Research Act of 1990 (P.L. 101-606), which called for "a comprehensive and integrated United States research program which will assist the Nation and the world to understand, assess, predict, and respond to human-induced and natural processes of global change." From 2002 through 2008, USGCRP was known as the U.S. Climate Change Science Program.
EPA has contributed to USGCRP Product 2.1a, Scenarios of Greenhouse Gas Emissions and Atmospheric Concentrations and Review of Integrated Scenario Development and Application. For more information or to download a copy of the report please visit USGCRSP Web page.
IPCC 4th Assessment, Working Group III Report, Mitigation of Climate Change
The report, prepared by the Intergovernmental Panel on Climate Change (IPCC), assesses greenhouse gas mitigation options in each sector of the global economy, addressing the economic and environmental costs and benefits of mitigation, the technical aspects of mitigation options, and potential cross-sectoral synergies and trade-offs. It also assesses the compatibility of near-term greenhouse gas mitigation activities with long-term climate stabilization pathways. Find out more about key findings from WG III on EPA’s IPCC 2007 page.