A series of climate-change projections are conducted with LOVECLIM, a threedimensionalEarth system model of intermediate complexity that consists of a quasigeostrophicatmospheric model, an ice-ocean general circulation model, a dynamicalmodel of the terrestrial biomass, a thermomechanical model of the Greenland andAntarctic ice sheets, and a model of the oceanic carbon cycle (which is not interactivein this study). Climate changes during the 21st century are first studied throughsimulations performed with the model driven by various IPCCs SRES scenarios forgreenhouse-gas and sulphate-aerosol concentrations. The model performance is assessedby comparing its results with similar results obtained with climate general circulationmodels. This analysis reveals that the model response is within the range ofcurrent uncertainty, although a bit weak. Stabilisation experiments are then carriedout over the whole third millennium to investigate the possibility of human-inducedabrupt climate changes.