These data represent 6-hourly instantaneous values of selected variables for ENSEMBLES (http://www.ensembles-eu.org). The list of output variables can be found in: http://ensembles.wdc-climate.de/output-variables. ENSEMBLES 20th century transient experiment (1860-2000 followed by IPCC A1B 2001-2100 and A1B 450ppm stabilization experiment) was initiated from year 1501 of the control preindustrial simulation when equilibrium was reached (corresponds to nominal year 1860 of 20C3M). Forcing agents included: CO2,CH4,N2O,O3,CFC11(including other CFCs and HFCs),CFC12; sulfate(Boucher). Additional forcings due to changes in land-use. These datasets are available in netCDF format. The dataset names are composed of - centre/model acronym (e.g. IPCM4: Institut Pierre Simon Laplace) - scenario acronym (e.g. SRA1B: SRES A1B) - run number (e.g. 1: run 1) - time interval (MM:monthly mean, DM:daily mean, DC:diurnal cycle, 6H:6 hourly, 12h:12hourly) - variable acronym [with level value] (e.g. hur850: relative humidity, 850 hPa) example: IPCM4_SRA1B_1_MM_hur850 For this experiment 3 ensemble runs were carried out. Technical data to this experiment: IPSLCM4_v2 (2007) : atmosphere : LMDZ4 (LMDZ4_V3_4, 144x143x19) ; ocean ORCA2 (ipsl_cm4_v2, 2x2L31); sea ice LIM (ipsl_cm4_v2); land ORCHIDEE (orchidee_1_9_3) The output from the model run is stored in: mercure.ccc.cea.fr:/dmnfs/cont003/p86denv/IGCM_OUT/IPSLCM4_v2/LU20C2