These data represent monthly averaged values (monthly mean (MM) and diurnal cycle (DC)) 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 The 450 ppm stabilization experiment (STREAM2 A1B) was initiated from year 2001 of the 20C3M run1,(corresponds to nominal year 2001 of STREAM2 A1B experiment). Forcing agents included: CO2,CH4,N2O,O3,CFC11(including other CFCs and HFCs),CFC12; sulfate(Boucher),BC,sea salt,desert dust aerosols. These datasets are available in netCDF format. The dataset names are composed of - centre/model acronym (e.g. CNCM33: CNRM/CM3) - 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: CNCM33_SRA1B_1_MM_hur850 For this experiment 2 ensemble runs were carried out. Technical data to this experiment: CNRM-CM3.3 (2008): atmosphere: Arpege-Climat v4.6 (T42L31); ocean: OPA8.1a5; sea ice: Gelato 3.10h; river routing: TRIP