These data represent monthly averaged values of selected variables for the Data Distribution Centre (DDC) of the Intergovernmental Panel on Climate Change (IPCC). (see also http://www.ipcc-data.org/) The model output prepared for IPCC Fourth Assessment SRES A2 experiment. These datasets are available in netCDF and GRIB format. This simulation was initiated from year 1980-03 of PCM1 model run B06.08 and executed on hardware blackforest.ucar.edu. The input external forcings are ozone forcing : noaao3.122yr.IPCC.041299.nc solar forcing : Hoyt/Schatten solar forcing, defined in code : see website for details GHGs : defined in code, see website volcanic forcing : none SOx emissions : SO4-A2.1980-2099.R.nc For this experiment there are 4 ensemble runs available. For model output data in higher temporal resulution and more variables visit the web page https://esg.llnl.gov:8443/home/publicHomePage.do.