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1
Our Common Journey

The test of our progress is not whether we add more to the abundance of those who have much; it is whether we provide enough for those who have too little.
Franklin Delano Roosevelt (Second Inaugural Address, January 20, 1937)

Over the last two decades, as appreciation of the challenge of "sustainable development" has very rapidly grown, the term has been used with diverse and evolving meanings in public debate and the scholarly literature. At the outset of our analysis, we therefore look at these various uses of the term. Next, we review action that has been taken in pursuit of sustainability goals since the 1987 publication of the World Commission on Environment and Development's report (often called "the Brundtland report") Our Common Future. In the heart of this chapter, we develop our concept of a "transition toward sustainability"—a transition over the early decades of the 21st century in which a stabilizing world population comes to meet its needs by moving away from actions that degrade the planet's life support systems and living resources, while moving toward those that sustain and restore these systems and resources. Moreover, this transition would move away from actions that widen disparities in human welfare and toward measures that reduce hunger and poverty. Ours is a normative vision of sustainability, which in our view is defined by the joint objectives of meeting human needs while preserving life support systems and reducing hunger and poverty. This vision is firmly anchored in the goals and aspirations of the world community as expressed through major international conventions and commissions of the past decade. Finally, in this chapter, we close with a brief exposition of the role of science and technology in this transition—a role that we see above all as one of fostering rapid and effective social learning.



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Page 21 1 Our Common Journey The test of our progress is not whether we add more to the abundance of those who have much; it is whether we provide enough for those who have too little. Franklin Delano Roosevelt (Second Inaugural Address, January 20, 1937) Over the last two decades, as appreciation of the challenge of "sustainable development" has very rapidly grown, the term has been used with diverse and evolving meanings in public debate and the scholarly literature. At the outset of our analysis, we therefore look at these various uses of the term. Next, we review action that has been taken in pursuit of sustainability goals since the 1987 publication of the World Commission on Environment and Development's report (often called "the Brundtland report") Our Common Future. In the heart of this chapter, we develop our concept of a "transition toward sustainability"—a transition over the early decades of the 21st century in which a stabilizing world population comes to meet its needs by moving away from actions that degrade the planet's life support systems and living resources, while moving toward those that sustain and restore these systems and resources. Moreover, this transition would move away from actions that widen disparities in human welfare and toward measures that reduce hunger and poverty. Ours is a normative vision of sustainability, which in our view is defined by the joint objectives of meeting human needs while preserving life support systems and reducing hunger and poverty. This vision is firmly anchored in the goals and aspirations of the world community as expressed through major international conventions and commissions of the past decade. Finally, in this chapter, we close with a brief exposition of the role of science and technology in this transition—a role that we see above all as one of fostering rapid and effective social learning.

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Page 22 Sustainable Development: Common Concerns, Differing Emphases "Sustainable development"—the reconciliation of society's developmental goals with its environmental limits over the long term—is the most recent conceptual focus linking the collective aspirations of the world's peoples for peace, freedom, improved living conditions, and a healthy environment. These four conditions frequently emerge as key ideals of the last half of the 20th century. Peace, the first, was thought to be secured in the postwar world of 1945. It was thereafter complicated by the nuclear arms race, then maintained globally but still fought locally in the long cold war, and is now sought again in places as diverse as Bosnia, Central Africa, the Middle East, and Ireland. Freedom proclaimed itself in the struggle to end imperialism, to extend human rights, and to end totalitarian oppression. Now, in the wake of establishing widespread national independence, development is the primary ideal that captures the hopes of the poorest two-thirds of the world, who aspire to both the basic necessities and the material well-being of the wealthy third. The most recently emphasized ideal has concerned the earth itself, initially focusing on natural resources, later extending to the human environment, and finally to the complex systems that support life on earth. Characteristic of the last quarter of a century is the effort to link all these aspirations of humankind—particularly through the realization of how often the pursuit of one condition requires pursuit of the others. International high-level commissions (such as the Independent Commission on International Development Issues 1980 [Brandt], the Independent Commission on Disarmament and Security Issues 1982 [Palme], and the World Commission on Environment and Development 1987 [Brundtland]), often followed by great international conferences, have attempted to make a case, moral and pragmatic, for such links. A specific recent focus has thus been on the critical relationships between development and the environment. Many notions now incorporated within the concept of sustainable development can be traced back through the 1980 World Conservation Strategy and the 1972 Stockholm Conference on the Human Environment to the early days of the international conservation movement.1 Today's understanding of the links between environment and development, however, is little more than a decade old, stemming from the Brundtland report, Our Common Future.2 The idea of sustainable development was given additional impetus at the 1992 United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro. It has rapidly spread and is now a central theme in the missions of countless international organizations, national institutions, "sustainable cities," and locales. The genius of the idea of sustainable development lies in its attempt

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Page 23 to reconcile the real conflicts between economy and environment and between the present and the future. Thus, the Brundtland Commission, in its widely accepted statement, defines sustainable development as the ability of humanity "to ensure that it meets the needs of the present without compromising the ability of future generations to meet their own needs."3 Within this general framework, an extraordinarily diverse set of groups and institutions have taken the concept of sustainable development and projected upon it their own hopes and goals. There have been extensive reviews of these diverse concepts and definitions.4 From these reviews, four types of key differences emerge. While sharing a common concern for the fate of the earth, proponents of sustainable development differ in their emphases on (1) what is to be sustained, (2) what is to be developed, (3) the types of links that should hold between the entities to be sustained and the entities to be developed, and (4) the extent of the future envisioned. (See Figure 1.1.) What Is To Be Sustained The emphases on what is to be sustained fall within three major areas: nature, life support systems, and community. The most common emphases concern life support systems, where the life to be supported first is human. Subsumed within this group are emphases on the classic natural resources—which, while found in nature, are particularly useful for people. Classified as either renewable or nonrenewable, flow or stock, these resources have preoccupied many generations seeking to exploit, conserve, or preserve them. In the last quarter of a century, the concept of natural resources has expanded, from a focus on primary products and production inputs to include the values of aesthetics, recreation, and the absorption and cleansing of pollution and waste.5 This extended view of natural resources becomes popularly associated with environment and the many features are defined by ecologists as ecosystem services.6 A recent study catalogued and valued 17 ecosystem services, ranging from atmospheric gas regulation to cultural opportunities.7 A less anthropocentric view of life and values is found in the emphases on sustaining nature itself for its own intrinsic value. The earth's assemblages of life forms, whether described as biodiversity in general, or as species or ecosystems in particular, are to be sustained not only for their utilitarian service to humans, but also because of humanity's moral obligations. These obligations are characterized as "stewardship"—acknowledging the primacy of humans—or as the proper response to a form of "natural rights" in which earth and its other living things have equal claims to existence and sustenance. Additionally, not only are biological species seen as endangered, but cultural species are as well. Thus, the

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Page 24 Figure 1.1 Sustainable development: common concerns, differing emphases.

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Page 25 concept of communities to be sustained covers distinctive cultures, particular groups of people, and specific places. What Is To Be Developed The emphases on what is to be developed also fall within three major areas: people, economy, and society. More often than not, when development is discussed, the emphasis is on the economy, with its productive sectors providing both employment and desired consumption, and wealth providing the incentives and the means for investment as well as funds for environmental maintenance and restoration. Yet another form of development stressed is human development. Such people-centered development focuses on the ''quantity" of life as seen in the survival of children or increased life expectancy, and on the quality of life in terms of education, equity, and equal opportunity. Finally, some discussions of what is to be developed adopt a broader conception of society, emphasizing the well-being and security of national states, regions, and institutions and, more recently, the valued social ties and community organizations known as social capital. The Links Between The concept of sustainable development links what is to be sustained and what is to be developed. The emphases differ according to whether the links are stated or implied. For example, the U.S. President's Council on Sustainable Development believes in "mutually reinforcing goals of economic growth, environmental protection, and social equity."8 It sees these goals as equal in importance and linked together. And is the operative conjunction between what is to be sustained, namely, the environment, and what is to be developed, namely the economy and society. But this is just one of many ways of envisioning the links between what is to be sustained and what is to be developed. Some views, while paying homage to sustainable development, focus almost entirely on just one of the two desiderata, the sustaining or the developing (thereby appearing to suggest "sustain only" or "develop mostly"). Others, while clearly emphasizing one or the other, subject this choice to a conditional constraint. For example, a Brundtland Commission member, noted "Sustainability is the nascent doctrine that economic growth and development must take place, and be maintained over time, [but] within the limits set by ecology in the broadest sense."9 Other views tend to leave to some set of publics or decision makers with determining the exact nature of and tradeoffs between what is to be sustained or what is to be developed.

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Page 26 For How Long? It is widely thought that sustainable development is meaningful only if it is intergenerational. Thus, there is general acceptance of the loosely stated time horizon of the World Conference on Environment and Development as now and in the future. The time horizons considered in specific contexts for future sustainable development, however, range from a single generation of 25 years or so, to several generations, as in the Intergovernmental Panel on Climate Change (IPCC) assessments that extend until 2100, to an unstated, but implicit, forever. Each of these time periods presents very different prospects and obstacles for sustainable development. Over the space of a single generation, almost any development appears sustainable. Over forever, almost none do, as even the smallest growth in numbers, resource use, or economy extended indefinitely creates situations that seem surely unsustainable. Over the century encompassed by many energy-environment assessments (e.g., those of the IPCC), the large-scale and the long-term dimensions of the future are both remote and uncertain. The sustainability of development in any usefully concrete sense is even more so. Sustainable Development: The First Decade The vision of the interdependence of development and environmental protection, first sketched in the Brundtland report, was fleshed out at the 1992 Rio Conference on Environment and Development (UNCED), oftentimes referred to as the "Earth Summit." The summit's "Rio Declaration" and "Agenda 21" together set forth detailed principles, action programs, and resource needs for achieving sustainable development in the 21st century.10 Following the Earth Summit, international conventions on biological diversity, climate change, desertification, and the law of the sea have entered into force. Ongoing negotiations are evaluating the implementation of these agreements and of other treaties adopted before the summit. A number of additional international conferences on sustainable development have been held, including conferences on small island developing states, population and development, social development, straddling and migratory fish stocks, women, human settlements, and food.11 Intergovernmental panels and forums are also considering problems of chemical safety, forests, and climate change. Finally, an uncounted number of regional, national, and local sustainable development initiatives have been undertaken in every corner of the world. A UN Commission on Sustainable Development (UNCSD) was established in the wake of the Earth Summit to monitor and report on imple-

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Page 27 mentation of the agreements reached in Rio. The commission's first review was tabled and discussed at a UN General Assembly Special Session in June 1997. The resulting UN resolution on the "programme for the further implementation of Agenda 21," supplemented by the assessments of other organizations and by analyses undertaken by the Board on Sustainable Development, suggests a sobering appraisal of the successes, failures, and unfinished business of the first decade of efforts to realize sustainable development. Many participants and observers at the UN special session concluded, with some justification, that efforts to implement the Brundtland and Rio agendas on sustainable development have failed. While Brundtland and Rio had been hailed as great successes, the leaders of the UN's 1997 special session could only make note of their countries' efforts to hold themselves accountable without implying that substantial progress had been made on previous commitments. Moreover, media and political attention to the environment have plummeted from their post-Brundtland report peak. Many participants in the special session have observed that the drive and optimism that characterized Rio seem to have given way to resignation and cynicism. Environment and Development Sustainability initiatives must ultimately be evaluated in terms of their impacts on patterns of environmental degradation and human development. The disappointing conclusion of the 1997 UN special session was that the impacts of sustainability initiatives on global trends in development and environment have been few, small, and slow. Backed by the UN Environment Program's recently published Global Environmental Outlook 2000,12 the special session noted: • While population growth rates continue to decline globally, the number of people living in absolute poverty has increased. • While globalization has presented new opportunities for sustainable development, many countries have been unable to take advantage of those opportunities; the extent of income inequality within and among nations, and the technology gap between the richest and poorest countries have all increased. • While a number of countries have significantly reduced some levels of pollution and slowed or reversed resource depletion, the state of the global environment has continued to deteriorate, with generally increasing trends of pollution threatening to exceed the capacity of the global environment to absorb them.

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Page 28 Funds and Financing Questions of resources and financing for sustainable development were problematic in the Brundtland report, contentious at Rio, and unresolved at the 1997 UN special session. The Global Environment Facility, an institutional product of the Earth Summit, was created to provide a funding mechanism for supporting the incremental costs of integrating global environmental goals into the development process. Its establishment, restructuring, funding, and replenishment are major accomplishments, but the total resources involved remain inadequate to the tasks at hand. More broadly, even the modest financial pledges made by governments at Rio have generally failed to materialize, substantially limiting the ability and willingness of developing countries to undertake important sustainability initiatives. These shortfalls in governmental assistance are to some extent compensated for by increased private investment flows into developing economies. But the volume of these flows, their ultimate destinations, and their implications for sustainability are not fully understood. Likewise, the relationships between financing sustainable development and regulating international trade and multinational corporate activities remain underdeveloped and poorly understood. The View from Below Despite these global concerns and disappointments, there is a more encouraging version of the story about sustainable development's first decades. This version holds that significant policy change of the sort sought by sustainability initiatives commonly requires a decade or more to come to fruition.13 With the Brundtland Commission's Our Common Future barely 10 years old, and the Rio "Agenda 21" only half that, it is then not surprising that most of these proposals' tangible impacts on people and the environment lie in the future. To see this view of the story, in short, requires a shift in perspective from a short-term, globally averaged vision of international diplomacy and the media to a longer term and more local view of sustainable development as it is happening on the ground. The abundant examples of local successes in sustainable development are not detailed in any one collection, although the submissions of individual countries and organizations to the UN Commission on Sustainable Development in preparation for the 1997 special session are a good place to begin.14 These local pictures are, of course, complete with their own share of environmental horrors, economic greed, and program failures. But compared with 20, 10, or even 5 years ago, the degree to which notions of sustainability have entered mainstream thinking is as-

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Page 29 tounding. Nongovernmental organizations (NGOs) and private corporations have been central to this transformation. Together with local and regional communities, they are carrying forward much of the ongoing work on sustainable development. Governments and international organizations have crucial roles to play in facilitating this work and in making sure that it does not leave pressing concerns unaddressed. The international scientific and engineering communities can make very significant contributions to sustainable development in particular sectors, areas, societies, and regions. Educators in early and continuing education can inform the general public about sustainability issues and make these issues an integral part of the university curricula relating to science, technology, and business. Whether these groups can in fact move beyond the verbal and political stalemate evident at the UN special session and learn to play their new roles effectively may be one of the most important questions in the next century, when the world's people begin their next appraisal of progress towards sustainability. Knowledge* and Know-How** As noted earlier, discussions of the role of science and technology have not been central to the last decade's debates on sustainable development. Few have denied the importance of mobilizing knowledge and know-how, but fewer still have applied themselves seriously to what this task might entail and how it might be done. Even Rio's "Agenda 21," drawing on the proceedings of the International Council for Science's (ICSU) International Conference on an Agenda of Science for Environment and Development into the 21st Century15 known as "ASCEND 21," devotes only 3 out of 40 chapters to science and technology and has little to say about priorities or their implementation. With so little to aim at, the 1997 UN special session did not even try to appraise the implementation of Rio's vague intentions for science and technology. Instead, it confined itself to a reiteration of general needs. In consequence, societies approach the 21st century with little in the way of a useful strategic appraisal of how to identify and create the knowledge and know-how most crucial to achievements in sustainable development. * Knowledge here refers to the Webster's Ninth New Collegiate Dictionary definition, "... the fact or condition of knowing something with familiarity gained through experience or association...or the acquaintance with or understanding of a science, art, or technique." ** Know-how here refers to the Webster's Ninth New Collegiate Dictionary definition, "knowledge [conveyed by expertise] of how to do something smoothly and efficiently."

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Page 30 Goals for a Sustainability Transition If the genius of sustainable development is to allow all in the common tent to project their hopes and goals, one limit of this valuable concept then is that it encompasses too much to provide a framework to map research and policy in the years ahead. Even if there were consensus on what specifically to sustain and what specifically to develop, and for how long, societies would not know how to arrive at these goals. The experience of efforts to adaptively manage natural resources and to cope with natural hazards is instructive—an experience partly captured in the metaphor of Compass and Gyroscope.16 In such situations, scientific understanding is incomplete, past policies have often failed, new policies are untested, and the unexpected is a recurrent truth. At best, science can provide compass direction, while the gyroscope of politics can maintain some steadiness of course across often-uncharted seas. In light of the trends of population growth, increased consumption, global connectedness and diversity, and environmental stress (see Chapter 2), a transition to sustainability appears necessary, but remote and difficult. Such a transition will entail meeting the needs and coping with the desires of many more people than there are today in the space of two human generations—which is just a few decades ahead. By 2050, UN demographers project a population of about 8.9 billion, with a range from 7.3 to 10.7 billion.17 Meeting the needs of that many people implies much greater consumption of energy and materials and the environmental and ecological problems that result from their extraction, consumption, and disposal. These problems will be compounded as more people adopt the materials-intensive, consumption-oriented lifestyle now enjoyed by industrialized nations. The increasing connectedness of economies, peoples, and technologies will fuel growth in some parts of the world, diminish it in others, and amplify the forces that drive increased consumption (see Chapter 2). Some environmental problems of the industrialized world will be exported to the developing and recently industrializing countries, and also, with some delay, the institutions and technologies to address them. In a more connected but still diverse world, differences in human experience will offer opportunities for alternative lifestyles and new possibilities for addressing our common future. Yet at the same time, increasingly widespread divisiveness may well make common tasks much more difficult. War, the ultimate expression of conflict, remains the greatest threat to human development, life support systems, and the environment. Driven by population growth and increasing consumption, past and current practices of energy and material transformation have led to the large-scale introduction of pollutants, the widespread destruction of biota,

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Page 31 and human-induced climate change—which are already threatening the life support systems of many local areas and a few regions. In the future, with large increases in total population and consumption, these environmental threats, cumulative and linked, could threaten the life support systems of entire regions and the globe. For a successful transition to sustainability, the world must provide the energy, materials, and information to feed, house, nurture, educate, and employ many more people than are alive today—while preserving the basic life support systems of the planet and reducing hunger and poverty. The Board has adopted this framework of a "transition toward sustainability" to help encourage movement over the next few decades toward meeting human needs in ways that do less damage to the physical and biological support systems for life, and more to sustain or restore them, along with movement toward development paths that do less to widen disparities in human welfare and more to reduce or eliminate hunger and poverty. In short, in the Board's judgment, the primary goals of a transition toward sustainability over the next two generations should be to meet the needs of a much larger but stabilizing human population, to sustain the life support systems of the planet, and to substantially reduce hunger and poverty. Using goals outlined in international conventions, we define meeting human needs as providing food and nutrition, nurturing children, finding shelter, providing an education, and finding employment. We define preserving life support systems as ensuring the quality and supply of fresh water, controlling emissions into the atmosphere, protecting the oceans, and maintaining species and ecosystems. We define reducing hunger and poverty as ensuring income growth, employment opportunities, and essential safety net services. Although the conventions and agreements we looked to for our definitions each have their own limitations, we believe that altogether they constitute a well-founded set of values and objectives on which to base discussions of sustainability. Their international input and endorsement ensures that the goals, which guide our transition toward sustainability, are relevant to and supported by governments and citizens worldwide. The Board's interest in focusing on the prospects for a global transition toward sustainability over the coming decades flows from our scientific understanding of trends in the environment, development, and associated problems. It is over the lifetimes of the next two generations of the world's citizens that we anticipate the greatest stresses arising through growing numbers and concentrations of people, extraordinary increases in energy and material throughput, and institutions just learning to cope with the barriers and opportunities of globalization. But if our scale of concern is based on technical understanding, our threefold conceptualization of a successful transition—meeting human needs, preserving life

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Page 48 Targets for Reducing Hunger and Poverty Meeting human needs for food, nurture, housing, education, and employment may help but does not ensure a reduction in hunger and poverty. If the target for feeding the world populations is to halve the number of hungry people in each of the next two generations, then by definition hunger would be reduced. This feeding of people would imply a reduction in poverty, since the world's poor spend some 85 percent of their income on food. Nurturing, education, and housing are less closely linked to alleviation of poverty. In general, the poor are less healthy, educated, and housed, but some poor countries have shown that it is possible to make dramatic increases in longevity, education, or access to clean water despite the large numbers of poor people. Even employment does not necessarily eliminate poverty: most of the world's poor work—indeed work very hard—but they receive little or no income from their labor. Thus, for a transition to sustainability, reducing hunger and poverty (as shown in the example of the "Hunger and Climate Change Reduction scenario" in the appendix to Chapter 3) requires conscious and simultaneous efforts in three directions: encouraging overall growth in income and employment opportunities, increasing the share of the increased income that accrues to poor and hungry people, and providing the crucial public services of nurturing, education, and housing. With evidence mounting that a substantial surge in the poverty rate in East Asia has followed the financial crises there, these efforts will be more difficult to achieve.63 The Transition to Sustainability as Social Learning A transition toward sustainability would be unprecedented; it has no charted course. The evidence from the first decade of efforts to achieve sustainable development shows that, in general, societies do not know how to do it. But the widespread experience of local efforts and successes is instructive and suggests an ability of societies to learn on the relevant scales. Hope for successfully navigating the transition in the future lies in conceptualizing sustainable development not as a knowable destination or computable trajectory, but rather as a process of social learning and adaptive response amid turbulence and surprise. What would it mean for society to learn how to better navigate a transition to sustainability? Scholarly studies of social learning over the large spatial and temporal scales of relevance are few but suggestive.64 On the social side, they include work on the shaping of social policy in Britain and Sweden, study of the long-term development of the international capacity to manage the spread of infectious diseases, analysis of the

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Page 49 spread and influence of Keynesian ideas in economic policy, and examination of the evolution of democratic norms and practices in Europe.65 In the environmental realm, there is a substantial body of scholarship on social responses to natural hazards, work on the Mediterranean, analysis of the Columbia Basin experience, studies on ecosystem management, review of policy learning in regional environmental management, and a forthcoming collaborative study on how societies around the world learned to deal with the risks of acid rain, ozone depletion, and climate change.66 While a coherent theory of social learning has not emerged from these works, several common themes stand out and we have drawn on them to guide the present study. Central to social learning in this context are many individual and group actions in response to change. But significant changes in societal responses to issues as complex as those involved in sustainable development generally require slow, interactive accumulations of scientific knowledge, technical capacity, management institutions, and public concern over periods of a decade or more. Moreover, while some adaptive learning can accrue throughout such extended periods, the more fundamental and important learning of changes in deeply held beliefs or perceptions of problems is rare and seems to require the impetus of crisis or surprise.67 A successful effort to promote social learning for a sustainability transition must therefore be expected to require patience and persistence over generations, while at the same time retaining enough flexibility to seize the moment when opportunities arise. The serious pursuit of social learning entails efforts to make sense of what is happening, to shape interventions informed by that awareness, and to interpret the consequences of the interventions against expectations of what might otherwise have occurred. All of these actions require a strategic perspective. For learning how to navigate the transition toward sustainability, such a strategic perspective will need to encompass large intervals of time and space, and facilitate an appreciation of the complex interactions of natural, economic, and social forces at work over those intervals. In short, societies must understand the long-term, large-scale trends and transitions that have shaped past and present interactions of environment and development. We attempt to sketch such historical perspectives on the transition to sustainability in Chapter 2. Looking forward, a strategic perspective on sustainable development does not mean a feckless quest to predict the future. Rather, it means thinking in an organized way about possible futures and the possible implications of present choices for them. Chapter 3 of this report summarizes recent work on the use of integrated assessment models, structured scenarios, and regional information systems to inform the strategic perspectives needed for learning how to achieve sustainable development.

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Page 50 If societies' efforts to navigate the transition cannot count on predictions of the future, neither are they condemned to simply steer into the darkness without an understanding of what lies ahead. If the scientific community does not know enough to say with confidence how the interactions of environment and development will work out over the relevant long-term and global scales, it can nonetheless do a good deal to heighten awareness of and preparations for the sorts of obstacles and opportunities that might be encountered along the way. This report attempts such a strategic reconnaissance in Chapter 4, employing past development experience and present scientific understanding to identify some of the most problematic environmental obstacles to human development that may be met in the transition to sustainability. The chapter then seeks to evaluate the potential social, technical, and environmental opportunities for circumventing or mitigating such obstacles, employing integrated strategies for the management of water, the atmospheric environment, and species and ecosystems. A fundamental requirement of social learning is feedback. In the report's analysis of efforts in social learning, the development, measurement, and reporting of appropriate indicators has been repeatedly singled out as one of the most important factors contributing to improved performance. Indicators can serve a variety of functions, from monitoring progress toward goals, through providing early warning of approaching hazards and detecting surprises, to assessing the effectiveness of particular interventions. The difficulty of designing indicators for use in promoting a transition to sustainability is to articulate what is needed and how the need for continued learning and response to surprise may be made part of the system for navigation. In Chapter 5 of this report, we develop a framework for indicators. One set of indicators is aimed at catching signals on different spatial scales to inform societies if they are on the right course in meeting goals for human needs and reducing hunger and poverty. These include monitoring biophysical circulatory systems,68 identifying critical regions, conserving productive landscapes, and preserving ecosystems. Another set of indicators evaluate the efficacy of actions taken to attain the goals. These include creating national capital accounts, analyzing policies, monitoring ongoing transitions, and conducting "surprise" diagnostics. Chapter 5 also discusses how to design, build, and maintain measurement and monitoring capacity, how to include the end users of the information, and how to use the scales of relevance. Social learning is a knowledge-intensive endeavor. It involves not only making use of and testing existing knowledge in new circumstances, but also the creation of new knowledge and know-how. The difficulty of creating knowledge and know-how to support the transition to

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Page 51 sustainability transcends not only national boundaries but also the individual human life span and the customary planning horizons of human enterprises. Developing a useful "sustainability science" will require novel approaches for research linking the natural and social sciences, and studying adaptive management and policy; for technology development and diffusion, to provide the most useful and needed tools for navigating the choices; and for institutions, to overcome barriers and find new funding mechanisms. Perhaps most challenging, sustainability science will require the design of new ways for learning from the uniquely large-scale, long-term experiments created every time a new technology, management scheme, or policy is tried out in the real world. The barriers to such learning are immense, but so are the potential rewards for overcoming them. Chapter 6 of this report provides a strategy for setting priorities for action to promote the life and livelihood goals described here, in navigating our common journey toward sustainability. References and Bibliography Adams, W. M. 1990. Green development: Environment and sustainability in the Third World. London: Routledge. Agenda 21. See UNCED 1992. Baskin, Yvonne. 1997. The work of nature: How the diversity of life sustains us. Washington: Island Press. Bean, Michael J. 1983. The evolution of national wildlife law. New York: Praeger Publishers. Bellagio Declaration. 1989. Overcoming hunger in the 1990s. Bellagio, Italy. Bennell, P., and Furlong, D. 1998. Has Jomtien made any difference? Trends in donor funding for education and basic education since the late 1980s. World Development 26, no. 1: 45–59. Bergesen, Helge Ole, and Georg Parmann. 1997. Green globe yearbook of international cooperation on environment and development. New York: Oxford University Press. Brandt Report. See Independent Commission on International Development Issues, 1980. Brown, B. J., M. E. Hanson, D. M. Liverman, and R. W. Merideth, Jr. 1987. Global sustainability: Toward definition. Environmental Management 11, no. 6:713–719. Brundtland Report. See WCED 1987. Burton, Ian, Robert W. Kates and Gilbert F. White. 1993. The environment as hazard. New York: Guilford Press. Caldwell, Lynton Keith. 1990. International environmental policy: emergence and dimensions. 2d ed. Durham: Duke University Press. Carincross, S., J. E. Hardoy, and D. Sattherwaite. 1990. The urban context. In The poor die young: Housing and health in Third World cities, eds. J.E. Hardoy, S. Cairncross, and D. Sattherwaite. London: Earthscan Publications. Chen, Robert S., and Robert W. Kates. 1996. Towards a food-secure world: Prospects and trends. In Global Environmental Change, 27–32. NATO ASI Series, vol. 37. London: Springer. Clark, W. C., and R. E. Munn, eds. 1986. Sustainable development of the biosphere. Cambridge, UK: Cambridge University Press.

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Page 57 York, March 27-April 12, 1995; women, United Nations Fourth World Conference on Women, Beijing, September 4–15, 1995; human settlements, United Nations Conference on Human Settlements, Istanbul, June 3–14, 1996; and food, World Food Summit, Rome, November 13–17, 1996. 12 UNEP (1999). 13 Weiss et al. (1997). 14 UNCSD (1997). 15 Dooge et al. (1992). 16 Lee (1993). 17 UN (1999). 18 Chen and Kates (1996). 19 FAO (1998). Although there is some hunger in industrialized or transitional economies, no international estimates exist. 20 WFS (1996), p. 1. 21 UNICEF (1993), p. 6. 22 UNICEF (1991), p. 35. 23 Dasgupta (1993). 24 WSC (1990). 25 UNCHS (1996a), para. 45. 26 UNCHS (1996b), pp. xxviii–xxix. 27 UNCHS (1996a), para. 45. 28 Op cit., para. 48a. 29 UNICEF (1999). 30 UNICEF (1991), p. 35. 31 World Declaration on Education for All, UNESCO (1990); World Summit for Children, UN (1990). 32 UNICEF (1991), p. 26. 33 UNICEF (1999). 34 Bennell and Furlong (1998). 35 UN (1995a,b). 36 UN (1995b). 37 OECD (1998). 38 Unemployment rates, UNDP (1998); unemployment data, ILO (1998). 39 ILO (1998). 40 UN (1997), Ch. VII, p. 18; ILO (1998). 41 UNICEF (1998). 42 Bellagio Declaration (1989). 43 "Agenda 21" of UNCED (1992), Ch. 19. 44 UN (1979), Article 2. 45 UN (1994a), Article 2. 46 UN (1985), Preamble. 47 UN (1992a), Article 2. 48 UN (1982), Article 1:1(4). 49 Op cit., Article 145. 50 Convention on the Preservation of Marine Pollution by Dumping of Wastes and Other Matter, London, Mexico City, Moscow, and Washington. 26 US Treaties and Other International Agreements 2403. Washington, D.C. 51 Convention for the Prevention of Marine Pollution by Dumping from Ships and Aircraft, Oslo. 11 International Legal Materials 262. Norway. 52 Inernational Convention for the Regulation of Whaling, Washington, 1946. 4 Bevans 248, US Treaties and other International Acts Series 1849. Washington, D.C.

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Page 58 53 UN (1958), Article 2. 54 UN (1950), Article 3. 55 Convention of the Conservation of Migratory Species of Wild Animals, Bonn. 1979. 19 International Legal Materials 15. Germany. Article 2. 56 Convention on International Trade in Endangered Species of Wild Fauna and Flora, Washington, 1973. US Treaties and Other International Acts Series 8249, Article 2. 57 UNESCO (1971), Article 2. 58 Bergesen and Parmann (1997). 59 UN (1994b), Article 3. 60 UN (1992b), Article 6. 61 E.g., World Bank (1999). 62 Sen (1981); Lipton (1988); Dasgupta (1993). 63 World Bank (1999); World Bank News Release (1999), No. 99/2214/S. 64 Parson and Clark (1995). 65 Social policy, Heclo (1974); infectious diseases, Cooper (1989); economic policy, Hall (1989); democracy, Eder (1987). 66 Natural hazards, Burton et al. (1993); Mediterranean, Haas (1990); Columbia Basin, Lee (1993) and NRC (1996); ecosystem management, Holling et al. (1978), Gunderson et al. (1995), Walter (1998); regional environmental management, Sabatier and Zafonte (1997); acid rain, ozone depletion, land, and climate change, Clark et al. (1999). 67 Clark (1990); Kates and Clark (1996). 68 As Chapter 5 explains, biophysical circulatory systems include rapid circulation in atmosphere and oceans, driven by solar energy and slower changes in the lithosphere as tectonic plates move, and in the biosphere as migration patterns shift and species radiate.