By William Clark and Nancy Dickson, Belfer Center for Science and International Affairs, Harvard University

The Global Environmental Assessment (GEA) Project is an interdisciplinary, international effort to better understand the role of assessment as a bridge between science and policy in matters of large scale environmental change. Over that period, a group of scholars drawn from the natural and social sciences have conducted research on the nature and effectiveness of a wide range of global environmental assessments covering issues of climate change, stratospheric ozone depletion, acid and other tropospheric air pollutants, desertification and biodiversity. Through this process, we have attempted to advance a common understanding of what it might mean to say that one assessment is more "effective" than another, not only from the perspective of national decision makers in the world's wealthier "core," but also from the position of leaders in countries of the developing world, decision makers at regional and local scales, and the scientists who give their time and energy to assessment efforts. We have sought to learn which factors have been systematically responsible for failures of assessment, and which have contributed to at least partial success.

The Project is based at Harvard University, but includes core faculty from a number of other institutions within and beyond the United States. We have tried to keep our efforts grounded in reality through a series of workshops that have engaged practitioners, users, and scholars of assessment in an off-the-record dialog that lets them compare insights and experiences. To date, the GEA Project has produced more than 30 working papers, the earliest of which have now begun to appear in the peer-reviewed academic literature. In addition, the Project and its workshops have provided ongoing practical input to efforts as diverse as the IPCC, the National Science Board's report on Environmental Science and Engineering for the 21^st Century, the US Global Change Research Program, the National Assessment of the Potential Consequences of Climate Variability and Change, and a number of national government agency planning efforts in the US and abroad.

Our studies have suggested that much about what makes some assessments more effective than others seems to be tied up with the process by which they are developed, rather than just the product itself. In particular, we have increasingly found it helpful to view assessments as a social process through which scientists, decision makers, and advocates interact to define relevant questions (while leaving others unasked), mobilize certain kinds of experts and expertise (while leaving others out), and interpret findings in particular ways. Such assessment processes can affect the social response to global environmental challenges in a number of ways. The effectiveness of an assessment should therefore be evaluated not only through its ultimate impacts on the environment (e.g., bringing about a decrease in damage due to acid deposition), but also through its influence on:

• the behavior of key actors (e.g., bringing about a decrease in emissions);

• the strategies of key actors (e.g., inducing active promotion of an international agreement to change emissions);

• issue frames and agendas (e.g., precipitating a decision to pay attention to an ENSO forecast, or to view the climate issue as one of poor peoples' vulnerability rather than rich peoples' emissions; raising concern for the acidification problem);

• the terms of the debate (e.g., introducing non-CO₂ greenhouse gases to the climate debate; introducing liming to set of options considered in the acid rain debate);

• the perception of knowledge needs (e.g., identifying a critical need for research on heterogeneous chemistry in the stratosphere).

The list is not exhaustive or unambiguous. Its importance is merely in stressing that assessments can and do exert their immediate impacts -- if any -- in a variety of ways. The particular paths of influence are a matter for empirical investigation rather than theorizing or assumption. Our research suggests the not surprising result that assessments exert their immediate impact on the policy process through the lower end of the list more often than they do through the higher.

Learning what distinguishes more from less effective assessments is one of the principal purposes, and deepest challenges, of our research program. We have therefore approached it stepwise, first identifying characteristics of assessments that seem to be differentially associated with high or low impact, and then working backwards to identify the underlying design choices that contribute to those characteristics. At this point in our investigations, three characteristics seem to be most important in distinguishing effective assessments: we have called them "saliency," "credibility," and "legitimacy." "Saliency," as we use it, is meant to capture the perceived relevance or value of the assessment to particular groups who might employ it to promote any of the effects noted above. "Credibility," as we use it, is meant to capture the perceived authoritativeness or believability of the technical dimensions of the assessment process to particular constituencies, largely in the scientific community. "Legitimacy," as we use it, is meant to capture the perceived fairness and openness of the assessment process to particular constituencies, largely in the political community.

Saliency, credibility, and legitimacy are not independent properties of assessments. Sometimes they overlap, as when an effort to achieve political legitimacy through greater sensitivity to the views of previously excluded stakeholders results in an increase in saliency of the resulting assessment to those groups. At other times, they seem to compete, as when an effort to increase political legitimacy through inclusion of multiple perspectives results in what many perceive to be a lowering of the scientific credibility of the result. Similarly, efforts to maximize the scientific credibility of assessments often drive them away from addressing the sorts of questions that would make them more salient to decision makers. It is such tensions and complementarities in the development of effective assessments that we hope to untangle or make sense of though our research and workshops.

If assessments become effective by being salient, credible, and legitimate, what imbues an assessment with these characteristics? These are the ultimate questions that drive our project. Current work is focusing on three sets of factors that we have found exert a substantial influence on the effectiveness of global environmental assessments: historical context (When in the evolution of an issue are different sorts of assessment most effective?), characteristics of the assessment user or audience (What sort of capacity does it take to be able to use an assessment?), and characteristics of the assessment itself (How does the institutionalization and process management of an assessment matter?). Studies of these and related questions are ongoing, with preliminary findings reported in our workshop proceedings and working papers. Those interested in commenting on or contributing to our studies, or in joining the GEA network, are invited to consult the project web site or contact us for further information.

For more information:

The GEA Project, its participants, and its research products are described in detail on the Project's web page: http://environment.harvard.edu. Further information is available from the authors at William_Clark@harvard.edu and Nancy_Dickson@harvard.edu .