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This chapter explores dystopian futures. After a summary of the uncertainties and risks discussed for each of the subsystems, integrated experiments are presented in which world view and management style throughout the world system are at odds. We also investigate the effectiveness of various response options and of the timing of certain policy measures.
In the previous chapter we outlined possible futures which are based on coherent sets of assumptions about how the world system functions and how it is managed. These are called utopias and constitute the diagonal elements in the matrix presented in Figure 10.7. In a way, they are idealised and therefore implausible images of the future. In this chapter we first present some simulation experiments in which dystopian trends are explored with the integrated TARGETS 1.0 model. This is a prelude to the next section in which we analyse in more detail images of the future where world view and management style are at odds. These are referred to as integrated dystopias (see Chapter 11) and they are actually more plausible because they contain real-world tensions between diverging world views and management styles. Two major chains which cause feedback loops are presented as a framework discussing some interesting dystopian futures and to give an assessment of associated risks. Finally, we explore the adequacy of response actions in terms of intensity and timing, and the consequences of allocating insufficient investments to the food, water and energy sectors.
The central question in this chapter is: can the world population be provided with an adequate and sustainable supply of clean water? We report on experiments with the AQUA submodel and attempt to offer insight into the role of population and economic growth, intensive agriculture, technology and pricing. Again three cultural perspectives are applied to establish model routes which reflect different assumptions and societal responses. The model experiments provide a number of water projections for the next century. We review low, medium and high risk developments and the effects of various water policy strategies. The chapter concludes with a proposal for future policy priorities to safeguard a sustainable supply of clean fresh water.
There are too many uncertainties to give a simple answer to the question whether we will have enough clean water for the next century. However, we can do some exploratory work if we make certain assumptions. In this chapter, we present such an exploration based on the AQUA submodel (Chapter 6). As a heuristic device for composing coherent sets of assumptions, different perspectives are used (see Chapter 10). First, we discuss some of the major questions, uncertainties and controversies related to water and sustainable development. We then look for coherence in the different points of view by considering the controversies from three perspectives: the hierarchist, the egalitarian and the individualist. Next, we use the three perspectives to implement ‘model routes’ within the AQUA submodel and to present model–based projections of water in the next century. Finally, we distinguish low, moderate and high risk futures, and analyse the effects of different water policy strategies. More detailed background information can be found in Hoekstra (1997).
We know that the future is inherently uncertain, yet we are fascinated by insights into ways in which we may be influencing the planet. This interest is intensified because there is widespread perception that the world is changing at an unprecedented speed. Undeniably, many parts of the global system are accelerating or decelerating compared to previously observed, natural rates of change. For some people these processes of change may just look like more of the same. There are, however, underlying behavioural and structural changes at work which suggest deeper, more radical change in the longer term. Many of those long-term changes can be viewed as part of transition processes. Several of these are within the human system: from many to 1 or 2 children per family, twice as many older people per thousand compared to today, a factor of 3 to 5 less energy and water use per unit of economic activity, increasing pressure to cultivate more land and use it more intensively to feed the population. More gradual, but possibly of overriding importance, are the changes in the environmental system, such as the accelerating increase in the concentration of some atmospheric gases and increasing accumulation of pollutants in soils and water bodies which are the result of past and present practices. It is difficult to disentangle the human-induced, structural long-term changes from the natural changes, which makes it even harder to see where the world is heading.
This chapter introduces Part Two of the book, which reports on experiments with submodels of TARGETS 1.0 carried out to assess a number of global change controversies. The experiments include a range of utopias and dystopias to discover whether the problem at the core of each controversy is likely to occur, and if so, under what conditions. The hierarchist utopia, which reflects the assumptions behind many reputable scenario studies, is used as a reference case to explore issues such as population growth, demand for food, water and energy, the environmental consequences of these pressures, and a range of societal responses. The results of integrated experiments with the TARGETS 1.0 model are presented at the end of this part of the book.
Part One of this book described tools for performing integrated assessments of global change. The aim of Part Two is to gain insights by using these tools, both withthe separate submodels and with the integrated TARGETS 1.0 model. The main goal of TARGETS is to put possible developments within the subsystems of the world into perspective in an integrated way. In this way we hope to provide a context for discussing global change and sustainable development. The quantitative modelling framework is used to support the qualitative framing of important issues. Though they are partial and limited in scope, the resulting images of possible global futures enable us to localise areas of tension and directions for sustainable development strategies.
This chapter introduces the integrated water assessment tool AQUA. This model has been developed to assist policy analysts assessing complex global water problems. A number of major long-term water policy issues are reviewed and AQUA is calibrated and validated against values in the literature. The model has been further validated at the regional level in studies that focus on the Zambezi and Ganges-Brahmaputra river basins.
Managing water resources has become an independent field of expertise and a separate domain of public policy. Nowadays, however, many problems of water scarcity and pollution interact with socio-economic development and environmental change to such an extent that a single discipline or sector approach can no longer provide satisfactory solutions. Water flows are purposely being regulated via reservoirs, dikes, canals, and irrigation and drainage schemes. However, runoff is unintentionally being affected by changes in land cover and soil degradation in many parts of the world; future water availability may be affected by climate change; and water pollution is often part of a disturbance of total element cycles. In developing countries, limited availability of clean, fresh water is a major cause of many diseases. The world's food supply increasingly depends on irrigated agriculture and thus again on the availability of fresh water. There is a growing recognition that studies should focus on the interlinkages and feedback mechanisms between water and (other) environmental and human systems (Young et al., 1994).
This chapter discusses an integrated water assessment tool, the AQUA submodel, that has been designed to analyse complex water problems which cannot be understood without adopting a comprehensive approach towards environmental change and socio-economic development.
When tackling a subject as complex as global change and sustainable development, it is essential to be able to ‘frame the issues’. This was one of the main reasons for developing the TARGETS model, an integrated model of the global system, consisting of metamodels of important subsystems. In this chapter we introduce TARGETS. Building on the previous chapters, we elaborate on the possibilities and limitations of integrated assessment models. Some of the key issues discussed are aggregation, model calibration and validation, and dealing with uncertainty.
One of the main tools used in integrated assessment of global change issues is the Integrated Assessment (IA) model. This chapter introduces such an integrated model, TARGETS, which builds upon the systems approach and related concepts introduced in Chapter 2. Previous integrated modelling attempts either focused on specific aspects of global change, for instance the climate system (IPCC, 1995), or consisted merely of conceptual descriptions (Shaw et al., 1992). We have tried to go one step further, linking a series of cause-effect chains of global change. Although we realise the shortcomings in our current version of the TARGETS model, we felt there was a need to present our model to a wide audience. We first give some advantages and limitations of IA models. Next, we discuss issues of aggregation, calibration, validation and uncertainty. We proceed with a brief description of the five TARGETS submodels which coincides with the PSIR concept and the vertical integration as introduced in Chapter 2. A more detailed description of these submodels is given in Chapters 4 to 8.
This chapter synthesises the insights gained from the model experiments made in the previous five chapters. The hierarchist utopia examined in Chapter 11 is only one possible future. We now explore the consequences of two other utopian futures: the egalitarian and the individualist. A selection of conditional forecasts from integrated simulation experiments with population, food, water and energy supplies, land use, global temperature and sea-level rise are presented. One way of looking at the model outcomes is by focusing on the various transitions which characterise the development of the human-environment system. Extending the time horizon of the model simulations into the 22nd century yields additional insights into the relation between the human and the environmental system.
The main goal of the TARGETS 1.0 model is to place possible developments within the subsystems of the world in an integrated perspective. In Chapters 12 to 16, simulation results of experiments with the TARGETS 1.0 submodels are discussed in isolation, while in Chapter 11 the results of an integrated simulation experiment for the hierarchist utopia are presented. In this chapter, we pursue this analysis further and include the other two perspectives. In this way we elaborate on the various controversies which have been raised in the preceding chapters: can a large population be maintained at an adequate health level and will there be enough energy, water and food without overburdening the natural environment? We start with the integrated utopias which are based on assumptions about world view and management style taken from a single perspective for all submodels (see Table 11.1).
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