Long-term perspectives on world metal use - a system-dynamics model

In this paper, a system dynamics model is described, which simulates long-t erm trends in the production and consumption of metals (i.e. iron/steel and an aggregate of metals of medium abundance) in relation to impacts such as ore-grade decline, capital and energy requirements and waste flows. This m etal model can be of assistance in exploring the issue of sustainability of metal resource use. Application of the model to historical trends shows it to be fairly capable of reproducing the long-term trends in the 1900-1990 period, among others on the basis of two intensity of use curves applied to 13 world regions. For future trends, a set of perspective-based long-term scenarios has been constructed that represent the major paradigms in resour ce use. These scenarios highlight some of the uncertain factors in the rela tion between economic growth, metal resource exploitation and use, and ener gy and environmental consequences. They also indicate that apparently simil ar metal flows in society may be the result of quite different and sometime s contrary assumptions on metal demand, production patterns and resource ba se characteristics. Such analyses contribute to a more open and transparent discussion on the issue at hand by adding quantitative explications to qua litative views. (C) 2000 Elsevier Science Ltd. All rights reserved.