GEO3 emphasizes that the next 30 years will be as crucial as the past 30 for shaping the future of the environment. Old troubles will persist and fresh challenges will emerge as increasingly heavy demands are placed upon resources that, in many cases, are already in a fragile state. The increasing pace of change and degree of interaction between regions and issues has made it more difficult than ever to look into the future with confidence. GEO3 uses four scenarios to explore what the future could be, depending on different policy approaches.
In GEO3 the models GLOBIO2 and IMAGE-NCI were first applied in parallel. These models are the predecessors of the current model GLOBIO3. GLOBIO2 was used to assess the impact of infrastructure expansion under the four GEO3 scenarios. IMAGE-NCI was used to assess the combined impact of various pressures in each of the scenarios. Pressures included are: population density, density of energy use, clear cutting, rate of temperature change and land use change.