Climate change impacts on the potential vegetation (biomes) are compared for an ambitious emissions-reduction scenario (E1) and a medium-high emissions scenario with no mitigation policy (A1B). The E1 scenario aims at limiting global mean warming to 2°C or less above pre-industrial temperatures and is closely related to the RCP2.6 sued in the CMIP5. A multi-model ensemble of ten state-of-the-art coupled atmosphere-ocean general circulation models (GCMs) is analyzed. A simple biome model is used to assess the response of potential vegetation to the different forcing in the two scenarios. Changes in biomes in response to the simulated climate change are less pronounced in E1 than in the A1B scenario. Most biomes shift polewards, with biomes adapted to colder climates being replaced by biomes adapted to warmer climates. In some regions cold biomes (e.g. Tundra, Taiga) nearly disappear in the A1B scenario but are also significantly reduced under the E1 scenario.