Figure 4.1. Population and economic growth from 1990-2100 under different development scenarios.

Gallopin et al. (forthcoming).
A Global Scenario Group (GSG), which also serves UNEP's GEO Scenario Working Group and is co-ordinated by the Stockholm Environment Institute (SEI), has so far focused on qualitative contours of three classes of scenarios: a central "Conventional Worlds" class; a pessimistic "Barbarization" class; and an optimistic "Great Transitions" class.

Conventional Worlds
Reference or Conventional Development scenario: already developed; analysed in this chapter.

Balanced Growth: stronger policy interventions; strong political will to implement policy reforms, strengthen management systems, and ensure widespread use of better technology; all to provide greater social equity and environment protection; many of the same patterns of production and consumption, notions of global governance, and political and cultural values as the Reference scenario.

Barbarization Scenarios
Breakdown: an extreme case of destructive anarchy; governmental and social failures, unchecked population growth, and environmental and social deterioration lead to scarcity, violence, and possible massive migration; eventually leading to economic collapse, a drastic fall in global population levels, loss of institutions, productive capacity, and technological wisdom.

Fortress World: an authoritarian "solution"; a minority of the elite in privileged enclaves protect their way of life by forcibly imposing limits and social controls on the impoverished majority, by seizing control of critical natural resources for their exclusive use, and by restricting access to information and technology; instability of a "Fortress" system may push the world into a "Breakdown" situation.

Great Transitions
Eco-communalism: a deep green utopian vision that emphasizes bio-regionalism, localism, face-to-face democracy, small technology, and economic autarky; population and economic scales diminish, environmental conditions improve dramatically.

New Sustainability Paradigm: seeks to alter the character of urban industrial civilization rather than to replace it; to build a more humane and equitable global civilization rather than to retreat into localism; a dramatic decrease of per capita material flows through behavioural changes and technology improvements, a resilient and high-quality environment, and high, well-distributed welfare with economic activity oriented towards services.

Although such futures may be viewed as utopian or unrealistic, the contrary hypothesis may be entertained as well, namely that attempting sustainability without such changes is quixotic.

The discussion of alternative futures raises a host of profound questions. Which of these pathways are self-consistent and plausible? Can the policy reforms of "Balanced Growth" achieve sustainability, or at least solve the urgent problems in many regions as identified in this GEO? What critical points could kick the system into global or regional "Barbarization" and what policies and actions are needed to reduce this risk? Can new values and policies transform industrial society as assumed in the "New Sustainability Paradigm"? And last but not least, the practical question for next GEO Reports: what actions are implied?