The CMIP5 experiements represented in NOAA's Climate Change Portal are the Historical, RCP4.5 and the RCP8.5. The historical experiments are forced with observed climate forcing (CO2, volcanos, solar activity) through the year 2005. The two future experiments are defined by strength of the radiative forcing in 2100, aka "representative concentration pathways" or RCPs. The CO2 emissions and the radiative forcing for each RCP are shown in the following figure.
More details on RCPs can be found in this paper.
We acknowledge the World Climate Research Programme's Working Group on Coupled Modelling, which is responsible for CMIP, and we thank the climate modeling groups listed here for producing and making available their model output. For CMIP the U.S. Department of Energy's Program for Climate Model Diagnosis and Intercomparison provides coordinating support and led development of software infrastructure in partnership with the Global Organization for Earth System Science Portals.
More information on the Coupled Model Intercomparison Project (CMIP5) and the 5th Assessment of the IPCC can be found here.
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