Expert Report

Each report is produced by a committee of experts selected by the Academy to address a particular statement of task and is subject to a rigorous, independent peer review; while the reports represent views of the committee, they also are endorsed by the Academy. Learn more on our expert consensus reports.

Global change assessments inform decision makers about the scientific underpinnings of a range of environmental issues, such as climate change, stratospheric ozone depletion, and loss of biodiversity. Dozens of assessments have been conducted to date by various U.S. and international groups, many of them influencing public policies, technology development, and research directions. This report analyzes strengths and weaknesses of eight past assessments to inform future efforts. Common elements of effective assessments include strong leadership, extensive engagement with interested and affected parties, a transparent science-policy interface, and well defined communication strategies. The report identifies 11 essential elements of effective assessments and recommends that future assessments include decision support tools that make use of information at the regional and local level where decisions are made.

Key Messages

  • A balance between the benefits of a particular assessment and the opportunity costs (e.g., commitments of time and effort) to the scientific community.
  • A clear strategic framing of the assessment process, including a well articulated mandate, realistic goals consistent with the needs of decision makers, and a detailed implementation plan.
  • A timeline consistent with assessment objectives, the state of the underlying knowledge base, the resources available, and the needs of decision makers.
  • Adequate funding that is both commensurate with the mandate and effectively managed to ensure an efficient assessment process.
  • An independent review process monitored by a balanced panel of review editors.
  • Careful design of interdisciplinary efforts to ensure integration, with specific reference to the assessment's purpose, users needs, and available resources.
  • Engagement and commitment of interested and affected parties, with a transparent science-policy interface and effective communication throughout the process.
  • Maximizing the benefits of the assessment by developing tools to support use of assessment results in decision making at differing geographic scales and decision levels.
  • Realistic and credible treatment of uncertainties.
  • Strong leadership and an organizational structure in which responsibilities are well articulated.
  • Use of a nested assessment approach, when appropriate, using analysis of large-scale trends and identification of priority issues as the context for focused, smaller-scale impacts and response assessments at the regional or local level.
  • The committee concludes that attention to these elements, many of which have been identified in the existing literature, increases the probability that an assessment will be credible, legitimate, and salient and therefore will effectively inform both decision makers and other target audiences.
  • The committee identified 11 essential elements of effective assessments: