持続可能性の実現に向けた将来シナリオ作成に関する研究の動向

抄録

Objective. Both scenario development and Life Cycle Assessment（LCA）are seen as useful methods to envision sustainable society. Through developing a scenario, scenario developers can clarify future possibilities, obstacles, and opportunities to achieve futures. LCA provides a comprehensive understanding about the social, environmental, or industrial systems. The purpose of this paper is to survey the history and current trend of the studies about scenario development and discuss relationships between scenario development and LCA. In this paper, we classify the studies about scenario development into the following two categories; studies about the scenario development methods and developing specific scenarios.

Results and Discussion. In detail, the scenario development processes categorized as follows; forecasting/backcasting, qualitative/quantitative, and participative/non-participative. In forecasting, developers explore the futures from the present situation, while in backcasting, developers depict the ideal future visions at first, followed by drawing the transition paths from the visions to the present. Participative processes are also a current trend, in which various stakeholders are invited to the scenario development processes. Stakeholder participation is useful for diversifying the contents of scenarios and by exchanging various points of view. Participative scenario development is a trial to combine democratic decision making with scenario development. A number of scenario development techniques are proposed for support developing, elaborating, and evaluating a scenario. Often, some of these techniques are integrated into scenario development processes. Many of existing scenarios are developed in forecasting processes combines qualitative and quantitative elements. LCA can be used as a tool in quantitative processes in scenario development. A number of current LCA studies includes several scenarios to tackle future uncertainty.

Conclusions. As sustainability problems are becoming serious, there are growing needs for scenario development for making decisions about research and development, policy making, and dissemination of sustainable technologies. Development of global LCA databases, a current trend of LCA studies, encourages applying LCA to global scale scenario developments. LCA combined with scenario approach is used for many sub problems of sustainability problems. Communication and outreach to citizens are essential for taking actions to achieve the sustainable futures envisioned through scenario development. Namely, studies to translate the professional perspectives into understandable form for citizens and to show the rationales of the futures depicted in the scenario are required. Participative scenario development processes are examples of such studies.