Avoiding ‘dangerous’ interference in the climate system : The roles of values, science and policy

The Intergovernmental Panel on Climate Change (IPCC) held a workshop in Fortaleza, Brazil (October 1994), to help provide the scientific underpinnings for the ultimate objective of the United Nations Framework Convention on Climate Change (UNFCCC): “… stabilization of greenhouse gas emissions at a level that would prevent dangerous anthropogenic interferences with the climate system …”. Scientists can assist in helping to identify exposureeffect relationships between changes in climate variables and the structure or function of ecosystems or socioeconomic sectors, and how these relationships might vary by ecosystem and location. But determination of ‘dangerous’ is not solely a scientific process: it involves judgments about what attributes of ecosystems and human activities are most highly valued and what level of change can be considered critical. In the future, further interaction is needed between the policy and scientific communities to help policymakers develop a better understanding of the complexities of the climate system and to assure that the scientific community provides information that is useful to evaluating alternative responses to climate change.