Outline of Interim Report from
"Research Committee on Sustainability in the Year 2050"

In the summer of 1994 the "Research Committee on Sustainability in the Year 2050" (Chairman: Yoichi Kaya, then Professor of the Faculty of Engineering at The University of Tokyo , and currently at Keio University) set up a working group of young specialists (Leader: Shunsuke Mori, Professor at Science University of Tokyo) to begin studies on the "physical conditions for sustainability." The members are specialists in population, resources, energy, agriculture and food, economics and other fields, all of whom are concerned with environmental issues.

In 1994 the meaning and concept of sustainability, the structure and background of problems in various fields, the physical conditions and restrictions, and problems among them were identified and discussed. This is an outline of the interim report of that discussion.

1. Introduction

(Shunsuke Mori/Professor, Department of Industrial Administration, Science University of Tokyo)

How can human beings seeking growth of the world's economy overcome the restrictions posed by factors of the environment, resources, and population? The solution to this problem, which used to interest only researchers, has become a very broad issue affecting the decision-making process. The Intergovernmental Panel on Climate Change (IPCC) and other organizations in Japan and other countries are studying this eagerly.

Our working group of specialists, focusing on a sustainable society and considering diverse aspects of energy, resources, food, economy and population, particularly seeks to link the perspective of each field and develop a model to assess the options comprehensively.

The starting points of our discussion were Meadows' "Limits to Growth" and "Beyond the Limits,", and the three well-known principles on sustainable technology and society by H. Daly.

The basic points that have emerged from our year-long discussion are as follows.

1. We have taken 2050 as a reasonable period of time for extra long-range sustainability evaluation, and will try to assess how technology and society will have approached towards sustainable society by that time.

2. We are taking into consideration only those technology systems which we expect to be realized by that time.

3. We regard as important not only potential physical supply but also the matter of distribution. Because behind the global environmental issues, there always exists the inequity between North and South.

4. We basically take a top-down approach. That is, we are attaching more importance to the interface between fields than simply assessing them individually. A model connecting these fields is thus necessary.

The mandate to our working group is so broad that it is impossible to examine all the aspects in one year. Now that we have identified our way of working, our specialists will make a systematic overview of the basic problems and the possible solutions to population, food, resources, energy and economy and to what degree the interdependence among these elements can be quantitatively assessed. Identifying how these interface, developing the model, and making concrete proposals for sustainability will be the work in the following year or later.

2. Concept of Sustainability

(Yasuhiko Ishida/General Manager, Global Environmental Policy Department, GISPRI)

Sustainable development has become the most important term in the world today, since it is password suggesting coexistence and development. The true meaning of the word, however, remains ambiguous and this is why, despite the three years that have passed since the Rio Summit, we still see no sign of solutions to the environmental problem. The term is sometimes mistaken for continuous development. From the standpoint that development can coexist with the environment, sustainable development is usually interpreted as change in a desirable direction; in this sense in the Japanese language 'hatten' is better than 'kaihatsu'. Since the global environmental issue is considered a critical one which human beings must solve, the concept of sustainability, which is the core of the matter, and standards by which to judge whether there is progress toward or achievement of the goal must be defined. It is our intention to examine this scientifically.

The initial step is to define whatshould be sustained, how and for how long. First, sustainable development does not mean development that is sustainable, but rather, such development that sustains society, or does not violate the sustainability of society. It is society itself that must be sustained. By this interpretation, there is no need to tie development and sustainability forcibly which may bring contradiction. Second, sustainability should mean to all members of society that sound satisfactory conditions will continue stably. Therefore, it is not only specific countries or districts which must be sustainable, but all nations and countries of the world ---- without this, there can be no true sustainability. Third, keeping in mind that it is important for us as people of today not to have a negative effect on future human beings and the ecosystem, we must think of sustainability in which we always have in view the distant future that today's activities can influence. Since it is our lack of consideration for the far future that has caused our current environmental problems, what is most needed now is to have a long-range perspective.

For society to be sustainable, each of the basic physical elements that maintains that society must be sustainable. Social conditions to keep those physical elements sustainable are essential. Each physical element ought to have certain conditions to assure its sustainability, and the first purpose of our research is to make these clear. Since various physical conditions are related to one another, there must be mutual sustainability among them.

If the conditions to keep society sustainable are clear, it will become possible to have a vision of society that satisfies these conditions, and what must be done to make such a society will then naturally be recognized. Since a sustainable society is a goal that can only be reached by practicable means, a vision of that society must be drawn which can be realized based on practical and workable techniques both technologically and sociologically. If realization of a sustainable society requires changing the materially affluent life that prevail today, there will inevitably be voices raised in opposition, stating that going backwards is impossible. Whether or not it is really going backwards, however, is a question of values. This is a mental barrier, not a physical barrier, and it can be overcome.

3. Population Problem and Sustainability

(Kazumitsu Nawata/ Associate Professor, College of Arts and Sciences, The University of Tokyo)

It goes without saying that in considering human sustainability, the population aspect is one of the most important. This must be approached with a long-range viewpoint, because decreasing the birthrate will take time, and even if the reproduction rate is lowered it will be a long time before the population of the world stops growing. At present it is increasing by over 90 million annually, so that the population problem each year is becoming more critical. If left unchanged, this single factor will threaten future human sustainability.

In developing countries, populations are continuing to increase rapidly. According to the UN's medium estimate, the world population, which was 5.3 billion in 1990, will be 8.5 billion in 2025, 10 billion in 2050, 11.2 billion in 2100, and by 2150 11.5 billion ---- more than double! Such rapid growth, particularly in developing countries, is anticipated to cause serious problems in the fields of politics, economy, the environment, resources, and food production. Moreover, the problems in these fields are in complicated relation to one another, which makes their solution difficult.

In this chapter, using the UN extra long-range population estimate, the influence of population growth to the year 2150 is quantitatively analyzed. First, the present situation and the future of the world's population are described on the basis of the UN estimate. Then, from among the problems anticipated as a result of this rapid increase, fossil fuel and food consumption and urban problems are addressed, and the influence on them caused by a population rise of the UN's intermediate level analyzed assuming several scenarios. The theory of population increase vs. the actual situation is discussed, and the world population conference are discussed as an example of international cooperation.

The population growth, primarily in developing countries, accompanied by per capita increase in consumption due to the rise in living standards brought by economic development, will increase demand for fossil fuel and food, and by the end of the 21st century is estimated to be several times larger than today. A steep rise in consumption by human beings at that time will occasion immense problems in the environment and limitation of resources. It is further expected that the population will, with increasing speed, be concentrated in cities in developing countries, swelling the urban populations there to several-fold the present number. Even in advanced countries, the concentration of people in urban areas is heightening problems of the environment, housing, transportation, and crime. Even today crowding is causing serious problems of health, poor housing and slums, particularly in developing countries. As stated, growth of the urban population will accelerate in the future and far exceed the capacity of many cities. This is likely to bring about confusion to society, the economy, and politics incomparable to anything known today, and will have a dire effect on human sustainability.

Based on the results of this chapter, this report will hereafter explain matters relating to energy resources and food supply, and the environmental and industrial impact which can result.

4. Structure of the Problem of Resources and Sustainability

(Ryuji Matsuhashi/ Associate Professor, Faculty of Engineering, The University of Tokyo)

The relationship between the structure of issues on resources and the concept of sustainability is analyzed. In a quantitative definition of the concept of sustainable limit of resources and the environment, the meaning of sustainability is proposed as: whether or not it is possible to sustain resources and the environment in the future if the present trend of demand continues. The necessary condition of sustainable use of resources comes down to improving the overall balance of use in the life cycle of resources and energy at a rate determined by present resource quantity and a level of waste concentration tolerable to the environment.

Given this definition, even if the life standard of a certain area is at the limit of survival, it is viewed as sustainable if they can sustain the level of living prevailing there. Therefore, the maximum permissible limit of sustainability should be allowed to change according to the level of fundamental human life.

For this reason, difference in sustainable limits is shown as corresponding to the estimate of population and energy demand in Chapter 3 (Cases 1 - 3). Here, growth rate of per capita energy demand in each case does not explicitly show the level of human desire (like Maslow's five stages), but the rates in developing and advanced countries are separately estimated. It can then at least be considered as one standard. The results here suggest that: in any of the three cases, the rate of improvement of the overall balance of use in the life cycle is quite high and not easy to achieve. As shown, the present situation of resource use is unsustainable (according to the definition here) either by resources consumption or by environmental emissions and the reader can see how far it exceeds the sustainable limit. Since the chapter does not sufficiently examine the effect, which regional differences in distribution will have on sustainability, this remains to be investigated.

Following the analysis of sustainable limits, ultra long-term global energy supply is simulated. It is shown here that present energy system, which depends mainly on fossil fuel, will shift to a sustainable system by imposing economic incentives in proportion to the distances from sustainable limits of resources and the environment. Distribution problems and urban problems proposed by this working group, as well as the means to deal with them will be taken up next.

5. Sustainability in Energy

(Koji Nagano/ Senior Research Engineer, Socioeconomic Research Center, Central Research Institute of Electric Power Industry)

Energy, which is an essential requirement for social and economic activities and development, is constrained by the limitation of resource deposits. Some of the fossil fuels (oil and natural gas) that human beings have depended on for energy to date are likely to run out in the near future. So long as we human beings depend on such exhaustible resources, it is impossible to realize a sustainable energy system, nor can we hope to establish a sustainable society. In other words, energy is the hardest barrier to overcome in realizing Sustainable Development. Looking back at the historical changes in our energy use, we can see that the main source we have used has shifted from wood and charcoal to coal, and further to oil, and natural gas. Here we must pay serious attention to the following two facts; the lasting time or the period when each of these major energy source of a given time continuously accounts for the largest share is getting shorter; and the next major energy source which will be needed about the middle of the 21st century has not yet been identified. These points clearly show how difficult it is to achieve a sustainable energy system. The 'North-South Problem' under the present energy use conditions, that is, the huge disparity of energy consumption between industrialized and developing countries aggravates the situation.

Information available up to now about the deposits of existing energy resources and waste material produced by energy use has been analyzed. According to the long-range estimate of energy consumption that has been made, petroleum will run out during the 21st century and natural gas will be exhausted even before that. Although coal deposits are abundant, the use of coal will have to be decelerated before dwindling deposits become a problem, because use of this substance imposes a heavy load on the environment. Based on the deposits of uranium, atomic energy could cover the demand of the 21st century, even if technology of the light-water reactor alone is assumed. However, as long as we depend on the technology of once-through fuel cycle by this reactor, we must bear in mind that atomic energy is also an exhaustible energy resource at any rate. It is true that the technology development to virtually set atomic energy free from the resource exhaustion, such as breeder reactors and adsorption of uranium in seawater are in progress, but the economic conditions of these technologies have not yet become competitive enough to be commercialized. Although the physical potential of renewable energy resources (biomass, solar, wind, etc.) is large, there is an enormous gap between the physical and the economic potential. There is much left to be done in future technological development.

It is thus extremely difficult to draw a blueprint of a sustainable energy system, because there are too many obstacles and uncertain factors. Overcoming these constraints will require innovative technologies. More concretely, an appropriate portfolio of research and development of energy technology must be put together. Here, those energy sources and technologies which are available today such as nuclear and coal should be regarded as a short- and medium-range stopgap measures; in the meantime the greatest efforts for research and development of innovative energy technologies centered on natural energy sources is should be made. An optimum long-term portfolio as such is needed in energy policy decision at present.

6. Problems in Sustainable Development of a World Economy

(Sumihiko Ohira/ Faculty of Business Information, University of Shizuoka)

There are various viewpoints on the definition of sustainable development of a world economy. In discussing this, the key term is intra-generational equality. In considering the global environment, discussion of the sustainable development of individual nation alone does not touch on the essence of the problem. Since the share of the population of developing countries is expected to greatly increase in the 21st century, it is impossible to deal with sustainable development without looking at intra-generational equality.

The world's economy is now at a turning point in history and there is a series of moves to find a new system and order after the Cold War. Success or failure in this will have great influence on the future of world economy. There used to be contrary views on strategies to advance developing countries, but today fundamental differences are diminishing, and investment in human resources, a competitive market economy environment, infrastructure, and relations to the world economy are now seen as more crucial.

Most important in considering the future development of the world economy is by what measure economic growth should be judged. In surveying the development of each country, per capita GDP has commonly been the index used, but in discussing sustainable economic development in relation to the overall environmental problem, it is a limited gauge. A many-sided evaluation of economic development by a social index like the HDI (human development index) of the United Nations Development Program (UNDP) is proposed as one which would consider broader social and economic factors. But this does not include factors of the environment. There is also a proposal to overcome the limitation by improving the GDP itself. Particularly in relation to the environmental problem, research on improving the GDP is being conducted by many institutes. In 1993 the UN published a revised version of SNA (System of National Accounts 1993) in which it is proposed that, apart from the traditional GDP, economic activities related to the environment be reported as Satellite Accounts. In Japan the Economic Planning Agency has already published the preliminary estimate of its environmental accounting. As mentioned above, research is vigorous on economic indices to directly evaluate human influence on the environment. Those indices will make it possible to take a proper quantitative approach to sustainable development in the near future.

To decrease the existing economic differences among countries, it is necessary for those still developing to industrialize to a certain extent. However, when the environmental problem is considered, it seems that the economies of today's advanced industrial countries are not necessarily good models. The biggest challenge of a future world economy is how the industrial structure of each country can be changed and an international division of labor be established so that the world economy as a whole can survive in harmony.

7. Sustainability in Food Supply and Demand

(Mitsuhiro Nakagawa/ International Research Coordinator, the Ministry of Agriculture, Forestry and Fisheries)

The world food problem as a whole has clearly been improving. Calorie supply per capita has continuously increased from 1,940 kcal in the early '60s to 2,500 kcal in the early '90s, and the percentage of the population starving in developing countries has decreased from 36% in the early '70s to 20% in the early '90s. There are regional differences, however; in the Sub Saharan Africa districts, Southern Asia, and parts of Central and South America, the food problem has been slow in improving, and among the lower income class in many developing countries there still remains a large malnourished group.

Though the rate of increase of the world's population is slowing, nearly 90 million people are added each year. Particularly, in many of the developing countries the population continues to increase by more than 2% annually, which is the main reason for the higher food demand. Rapid economic growth is expected in many developing countries of Asia. With the rise of per capital income, demand for livestock products, feed grain, oils and fats, and fruit is predicted to increase.

In contrast, the environmental problems of global warming, acid rain, deforestation of the rain forest, desertification, etc. are becoming more serious, and are matters of concern that may have a negative effect on the long-term food supply. About global warming, it is anticipated that as the emission of CO₂and other gases producing the greenhouse effect increase, the temperature will rise at the rate of 0.3^?C in ten years and sea level will rise at the rate of 6 cm in that same period, which may necessitate shifts in production sites, reduction in the area of farmland and further changes in crop production. Acid rain is now found in many parts of the world, and acidification of the soil and lakes and deforestation are continuing. The rain forest is disappearing at the rate of 17 million hectares a year, an area half as large Japan's entire land mass; this is causing land erosion, floods in the lower river basins, species extinction, and decrease in biomass resources. Excessive cultivation, overgrassing, and collection of too much firewood are making deserts of about 20 million hectares of farmland each year and hindering the growth of food in arid.

These environmental problems are slowing the increase in cultivated and irrigated land, and also the rate of increase of crop yield. Since restrictions on land and water resources are tightening, crop yield must continue to rise by technological progress in order to meet the increasing demand for food caused by population growth and higher income. Investment must be made in agricultural research and infrastructure put in place. At the same time, since the food problem is closely related to that of distribution, comprehensive development measures including those of income and marketing must be taken.

8. Approach to Sustainability through Extra Long-range Global Warming Simulation

(Shunsuke Mori)

The problems in the economy and the environment are global and long-range ones. The complicated relations twining around all global challenges including resources, energy and economic activities as well as agriculture, population, and climate change must be disentangled. In the matter of global warming, in addition to long-range physical forecasts by meteorological and ocean-air circulation models, various attempts are being made to estimate the outcome of diverse techniques and policy options quantitatively in a model. These are often called as an integrated assessment model approach that research institutes of many countries of the world are now working on. Among others, Stanford University sponsors an international academic meeting called EMF-14, where model researchers actively exchange opinions. Our working group investigated the development trend of these models and the outline. As a prototype for model development, a Model Approach for Resource and Industry Allocation is discussed which, dividing the world into three parts, enables an extra long-range simulation of energy, economy and global warming. At the present stage, factors of biology, agriculture and forestry, and land utilization are not included in this model; climate change is also viewed in a very simplified manner. However, the model makes it possible to calculate what influence the following measures will have on long-range global warming and economic activities separately in Japan, in other OECD countries, and in the rest of the world. Here, a simulation is made based on the following assumption:
CASE A: The present situation continues. Atomic energy is included up to the maximum technical limit.
CASE B: The allowable introduction of atomic energy is restricted to 50%.
CASE C: The total amount of CO₂ discharge in the world is stabilized at the 1990 level, and emission rights of individual countries are recognized as exchangeable.

It is shown here that if the present consumption situation continues the atmospheric temperature will rise by 3^? at the end of the 21st century and that even if the amount of CO₂discharge is stabilized at the 1990 level, the temperature will continue to rise, but only about 1.6^?C degree.

As a step toward future expansion, furthermore, blocks for food supply, demand for wood, and land utilization to assess the option of absorbing CO₂ by biomass energy production and forest are added to this model. This expansion hypothesis and the results of its simulations are additionally described. Many problems are left unsolved in the model in areas of resources, food, technology and economy, but it is viewed as a significant attempt to at least suggest a direction for future research.

9. Conclusion.

(Shunsuke Mori)

We consider in this research the matter of the environment to be a necessary condition of society in which human beings can survive permanently and enjoy a fulfilling life, and we have used as a keyword: sustainability. We have examined what problems are hidden in the concept of this word, which at first glance seems self-evident, what prospects are actually realistic in each of the fields of resources, population, energy and food, and what kind of future can be envisioned when we think about their long-range interrelationships.

The important charge of this research is to draw as concrete an image as possible of what a sustainable society is like if each can be realized or if any society is now approaching it. We selected 2050 as the time when, if we direct our society in that direction, it is possible that something might be realized through the decisions we are making today.

In Chapter 2 we first put in order various concepts concerning sustainability. In Chapter 3 we examined the most influential problem of population as it relates to urban conditions. In Chapter 4 we considered evaluative methods based on long-range viewpoints of how resources and their finiteness will curtail mankind in future. Sustainability in energy was examined in Chapter 5, while in Chapter 6 we dealt with the factors of economy and industrial structure that support a sustainable society. In Chapter 7 we described the present condition and the prospect of a problem of food supply which is basic for human beings. In an attempt to quantitatively assess the correlation among those issues, we showed in Chapter 8 an integrated assessment model approach and simulation results of a prototype model.

Although the problems are so enormous that we have not achieved comprehensive solutions in the first year, through the research and discussion we have identified certain obstacles and different viewpoint in each field that may await us as now known; these have potential to restrict the continuous development of the world and we have identified courses of methodology that appear possible to actually integrate them.

We plan now to look at individual possibilities as to how technology and social systems in each field will function in the course of realizing a sustainable society.

As mentioned at the beginning of this report, however, ours is not a world in which decisions are made by a single entity. Countless problems will require resolution along the way as we seek minimum conflict in this multiplex structure from individual to species, and from survival to self-realization.