Not 2 Green  |   The Future

  Final Government Distribution   -   Glossary   -   IPCC AR6 WGI       August 2021

Climate model  -  A qualitative or quantitative representation of the climate system based on the physical, chemical and biological properties of its components, their interactions and feedback processes and accounting for some of its known properties. The climate system can be represented by models of varying complexity; that is, for any one component or combination of components a spectrum or hierarchy of models can be identified, differing in such aspects as the number of spatial dimensions, the extent to which physical, chemical or biological processes are explicitly represented, or the level at which empirical parametrisations are involved. There is an evolution towards more complex models with interactive chemistry and biology. Climate models are applied as a research tool to study and simulate the climate and for operational purposes, including monthly, seasonal and interannual climate predictions. See also Chemistry-climate model, Earth system model (ESM), Earth system model of intermediate complexity (EMIC), Energy balance model (EBM), Simple climate model (SCM), Regional climate model (RCM), Dynamic global vegetation model (DGVM), General circulation model (GCM) and Emulators.
 
Climate prediction  -  A climate prediction or climate forecast is the result of an attempt to produce (starting from a particular state of the climate system) an estimate of the actual evolution of the climate in the future, for example, at seasonal, interannual or decadal time scales. Because the future evolution of the climate system may be highly sensitive to initial conditions, has chaotic elements and is subject to natural variability, such predictions are usually probabilistic in nature