| Climate model |
Complex mathematical representation of the Earth ’s climate system coupling many physical processes (i.e. atmosphere flux, ocean circulation, land surface and sea ice dynamics, snow cover, and permafrost) [2]. |
| Forcing scenario |
Hypothesis of the modification of the balance of incoming and outgoing energy in the Earth-atmosphere system. The new generation of forcing scenarios, the Representative Concentration Pathways (RCPs), provides potential greenhouse gas concentration trajectories for the future whereas the Emissions Scenarios (SRES) hypothetize the greenhouse gas emissions in the atmosphere. |
| Initial conditions |
In climate models (chaotic systems), initial conditions refer to starting values of climate variables at a given place and time. Small changes in these starting values could lead to different paths of the climatic system. |
| Climate change scenario |
Potential future climate projected by a climate model under a specific forcing scenario and initial conditions. In general climate change scenarios are available for 30-year periods. |
| Ensemble forecasting |
Large number of copies of a system, each of which represents a possible state of this system. In climate change science, ensemble forecasting consists in using climate change scenarios obtained from different climate models run under different forcing scenarios and different initial conditions. |
