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 https://www.ipcc-data.org/) The model output prepared for IPCC Fourth Assessment climate of the Pre-industrial control experiment (picntrl). These datasets are available in netCDF and GRIB format. Begining from an ocean initially at rest, with (T,S)=Levitus data (1982), clim. sea ice and atm. + GHG, aerosols for 1860, the model was run for 20 years with (T,S) restoring at the ocean surface. Then the model was run without relaxation for 71 years. The 71th year was used as initial condition to the preindustrial simulation. Forcing agents included: CO2,CH4,N2O,O3,CFC11(including other CFCs and HFCs), CFC12; sulfate(Boucher),BC,sea salt,desert dust aerosols. For this experiment there is only one run available. Model output data for CMIP3 in higher temporal resolutions and further variables are available in ESGF at https://esgf-node.llnl.gov/search/cmip3/.