Global Models
What are Global Models?
Global Models are computer simulation models that are distinguished from other computer simulations by virtue of three characteristics. They are:
1. The geographic scope of the model is the entire world or at least a significant portion.
2. The model attempts to span and link significantly different subject areas such as the environment and the economy.
3. The model attempts to track or forecast the evolution of the world (in its subject areas) over time.
More accurately (but awkwardly) referred to as Integrated Global Models, global models have been in development since the late 1960's. Among the early models that attracted attention (some might say gained notoriety) are:
1. World2, which was presented in the book World Dynamics.
2. World3, which was originally presented in The Limits to Growth and reused in an updated form in Beyond the Limits.
3. WIM (World Integrated Model but also called the Mesarovic-Pestel Model), which was introduced in Mankind at the Turning Point and described in World Modeling and a number of papers.
4. LAWM (Latin American World Model ), which was presented in Catastrophe or New Society?
5. WIOM (World Input-Output Model but also called Leontiev Model and UN Model), which was presented in The Future of the World Economy and numerous published papers.
6. FUGI Model (FUture of Global Interdependence ), which has been presented in Global Model Simulation and several published papers.
Several other models attracted less attention but deserve inclusion in the group of models presented here. Among them are:
7. SIM/GDP (System of Integrated Models/Global Development Processes ), which was described in several articles written in Russian and a few in English.
8. RW-III (Regional World-III ) and its successor,
9. IWM (Integrated World Model but also called Regional World-IV).
10. SARUM (Systems Analysis Research Unit Model ), which spawned a number of successors and publications describing them.
Subsequent Integrated Global Models of this type include:
11. IFS (International Futures Simulation ) which is still under development and is presented in International Futures.
12. GLOBUS (Generating Long-term Options By Using Simulation ), which was presented in The GLOBUS Model and other papers.
13. IMAGE (Integrated Model to Assess the Greenhouse Effect ), which was presented in the book Image.
Other Global Models
There are many more global-scale models than those presented above. Most of these other models are of three types:
- Economic models focusing on macroeconomics, trade, and investment
- Global atmospheric models, usually referred to as GCMs (General Circulation Models)
- Ocean models
Much recent work in making new Integrated Global Models (now often called Integrated Assessments) centers on linking GCMs with ocean models and linking economic models with GCMs.
An excellent place for the interested reader to learn more about integrated global models and other related simulations is Gottfried Mayer-Kress's GlobalModels Web page.
Peter Brecke … Sam Nunn School of International Affairs … Georgia Institute of Technology … Atlanta, Georgia 30332-0610 USA … Tel 404 894-6599 … Fax 404 894-1900 … Email peter.brecke@inta.gatech.edu