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The Century Ahead: Searching for Sustainability The Century Ahead: Searching for Sustainability

 

1. Introduction

 

Concern about the sustainability of nature and society is rising, and with good reason. Scientists report with ever-greater urgency the need for action to avoid destabilizing climate change and widespread destruction of the world‘s ecosystems [1,2]. Parallel efforts are required to ease looming shortages of critical resources such as oil, water, and food. Meanwhile development specialists call for mitigating poverty, strengthening social justice, and enhancing human well-being. Other observers appeal for more effective transnational governance to regulate the growth and impact of globalizing capital, finance, and product markets that threaten the long-term stability and fairness of the world economy.

 

These concerns are central to the broad challenge of sustainable development, an international commitment assumed, at least rhetorically, nearly two decades ago at the 1992 Earth Summit in Rio de Janeiro. At the core of the concept of sustainability lies a moral imperative to pass on an undiminished world to future generations. This clarion call to take responsibility for the welfare of the unborn requires that, in making choices today, we weigh the consequences for the long-term tomorrow.

 

This paper explores the implications of this challenge by considering four contrasting global scenarios representing alternative worlds that might emerge from the turbulence and uncertainty of the present. Market Forces and Policy Reform are evolutionary futures that, despite episodic setbacks, emerge gradually from the dominant forces governing world development today. The other two envision a fundamental restructuring of the global order: fragmentation in Fortress World and positive transformation in Great Transition. Each scenario tells a different story of the twenty-first century with varying patterns of resource use, environmental impacts, and social conditions.

 

It is important to note the distinction between scenarios and forecasts. The interactions among co-evolving human and environmental systems are highly complex and inherently uncertain, rendering predictive forecasts impossible in any rigorous statistical sense [3,4]. Instead, scenarios are intended as renderings of plausible possibilities, designed to stretch the imagination, stimulate debate, and, by warning of pitfalls ahead, prompt corrective action. Of course, the plausibility, and even the internal consistency, of different visions is itself uncertain. How will the climate system respond to increased greenhouse gas concentrations from human activity? What geo-political formations will emerge? How will human values adjust? Indeed, limiting the ways surprises and feedback might knock a scenario off course is an illuminating and underappreciated aspect of scenario analysis.

 

We have examined our scenarios in great quantitative detail to the year 2100 for eleven world regions. The summary presented here focuses on selected global-scale results, painting broad-brush pictures of these contrasting futures, and revealing the fundamental forces driving development away from or toward sustainability. Cross-scenario comparisons offers lessons for policy strategies, institutional change, and, ultimately, for human values.

 

This research updates and enhances an earlier series of scenario assessments conducted by the Tellus Institute on behalf of the Global Scenario Group [5-7]. The base year has been advanced from 1995 to 2005, adding ten additional years to the massive database on which the analysis rests. That data feeds the PoleStar System, a computational framework originally developed in the early 1990s by the Tellus Institute and the Stockholm Environment Institute. PoleStar is designed to explore a full spectrum of integrated long-range scenarios in quantitative detail, including unconventional pathways of structural discontinuity [8].

 

The global simulations are disaggregated by region, major sectors and subsectors of the economy, key social variables, and numerous aspects of the environment and natural resources (see Table 1). Assumptions and computations are documented in [9], with regional results reported online at http://www.tellus.org/result_tables/results.cgi.

 

Table 1. Key issues simulated.

 

Sectors:

 

  • Social
  • Population
  • Gross Domestic Product (GDP) and value-added by sector
  • Income (GDP per capita)
  • Income distribution within and between regions
  • Poverty
  • Hunger line (income for adequate diet)
  • Employment (productivity and length of work week)

 

  • Household
  • Energy use by fuel
  • Water use
  • Air pollution
  • Water pollution

 

  • Service
  • Energy use by fuel
  • Water use
  • Air pollution
  • Water pollution
  • Transportation
  • Passenger by mode: public road (buses, etc.), private road, rail, air
  • Freight transportation in following modes: road, rail, water, air
  • Energy use by mode and fuel
  • Air pollution

 

  • Agriculture
  • Diet by crop and animal product categories
  • Livestock: animal type, seafood (wild, farmed), other products (milk, etc)
  • Crops: coarse grains, rice, other (fruits, vegetables, etc.), sugarcane, biofuels
  • Energy use by fuel
  • Irrigation
  • Fertilizer use
  • Air pollution
  • Water pollution

 

  • Industry
  • Energy use by fuel and subsector: iron and steel, non-ferrous metals, stone, glass, and clay, paper and pulp, chemical, other
  • Energy feedstock by subsector.
  • Water use by subsector
  • Air pollution from both fuel combustion and process
  • Water and toxic pollution

 

  • Forestry
  • Primary wood requirements
  • Secondary wood for final demand, and input to paper and pulp, lumber, biofuel

 

  • Land-Use
  • Conversions between built environment, cropland, pasture, forest types (unexploitable, exploitable, plantation, and protected), other protected (marshes, bays, etc.), other
  • Each category broken down by arable and non-arable areas
  • Cropland disaggregated by crop type, and irrigated/non-irrigated

 

  • Energy Conversion
  • Conversion from primary to secondary fuels (i.e., electricity production and oil refining)
  • Requirements for coal, biomass, natural gas, renewable (wind, solar, geothermal, etc), crude oil, nuclear, hydropower
  • Air pollution

 

  • Water
  • Freshwater resources
  • Desalinization and waste-water recycling for water resources
  • Use-to-resource ratios
  • Water stress

 

  • Solid Waste
  • Generation from household and service sectors
  • Landfill, incineration, recycling and other disposal technologies
  • Energy generation from incineration

 

 

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