Emerging environmental issues are issues that may someday be of concern but that have not yet been generally recognized. A review of such issues that have occurred over the last 50 years reveals that many of them have erupted rather suddenly (e.g., stratospheric ozone depletion, acid rain). However, some issues were recognized long ago by the scientific community (e.g., land degradation, overconsumption of freshwater), but for economic or other reasons governments have refused to act.

The authors of this study were commissioned by the United Nations Environment Program and the Scientific Committee on Problems of the Environment to carry out a global survey of emerging environmental issues, using the responses received to questionnaires that were sent to scientists, managers, and policy makers around the world. It had been hoped that a short list of priority issues could be identified but the number of issues was very long. However, the issues could be divided into four major classes:

  • Transformations of old issues; continually evolving, and in most cases broadening, in response to increasing scientific and technological knowledge and to changing socioeconomic, cultural, and environmental conditions.

  • Policy issues, the long-term environmental consequences of which may already be of concern.

  • Accidents waiting to happen, for example, chemical time bombs.

  • Surprises in the nonlinear responses of ecosystems to new and different stresses, as well as in the nature of socioeconomic drivers of environmental change.

In a subsequent study, the authors applied the lessons learned in the global study to an examination of emerging environmental issues in the province of Ontario, Canada.

This content is only available as a PDF.


*Institute for Environmental Studies, University of Toronto, Toronto, Ontario, Canada.

+Mestor Associates Ltd., Russell, Ontario, Canada.