SSP_scenarios_Emissions_EN_5_Scenarios_600.pngIn addition to the main scenarios SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5 ("Tier 1 Experiments") simulated for ScenarioMIP by a large number of models, some centers have also performed simulations for the climate change scenario SSP1-1.9. This fairly optimistic scenario requires the strongest and most expeditious climate mitigation actions and is roughly equivalent to a 1.5°C scenario; here, global mean temperature changes by less than 1.5°C relative to pre-industrial levels. The moderately optimistic scenario, SSP1-2.6, corresponds to a 2°C scenario, but even this requires a fairly rapid shift away from fossil fuels and further action. The intermediate scenario, SSP2-4.5, assumes a stabilization of greenhouse gas concentrations at a somewhat elevated level, but exceeds the 2°C warming global mean and thus possible tipping points in the climate system. In the case of the moderately pessimistic scenario SSP3-7.0, a stronger warming is already simulated as a consequence of insufficient climate protection measures. The strongest warming results from the simulation for the pessimistic scenario SSP5-8.5, which assumes further strongly increasing emissions.

All visualizations of the results of the mean of all CMIP6 models presented here were produced at DKRZ. The multi-model means were calculated and provided with the Earth System Model Evaluation Tool (ESMValTool) from the German Aerospace Center (DLR).

Video 1:

Direct comparison of temperature changes for the "2°C scenario" SSP1-2.6 (roughly equivalent to CMIP5 scenario RCP2.6) and the pessimistic scenario SSP5-8.5 (equivalent to CMIP5 scenario RCP8.5) shows the range of scenarios used for the last model intercomparison project CMIP5 and the 5th IPCC report. In both cases, the continents warm faster than the ocean regions, and the Northern Hemisphere warms more than the Southern Hemisphere. The warming is particularly pronounced in the Arctic; in the case of SSP5-8.5, the warming there is significantly more than 10°C.

Video 2: This visualization shows the extended range of temperature changes projected by the CMIP6 ensemble for scenarios SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5 compared to the 1995-2014 period. As expected, it shows a graded warming according to the strength of radiative forcing. While natural variability still dominates at the beginning of the animation, a typical warming pattern quickly emerges, especially in the simulations with higher CO2 concentrations: the continents warm faster than the ocean regions, and the northern hemisphere warms more strongly than the southern hemisphere. The warming is particularly strong in the Arctic.

Visualization: Michael Böttinger, DKRZ,  Data preparation: Axel Lauer und Veronika Eyring, DLR

References: Eyring et al. 2016, GMD, 9, 1937-1958, 2016,, Tebaldi et al. 2021, Earth Syst. Dynam., 12, 253–293, 2021,

References on ESMValTool: Eyring et al 2020.,, Lauer et al. 2020,, Righi et al. 2020,, Weigel et al. 2021,

CMIP6 Ensemble Temperature Changes (separately)

Here, for each of the 5 simulated SSP scenarios, we show the time history of the temperature changes projected by the CMIP6 multi-model ensemble relative to those for the 1995-2014 period.