Choosing Indicators and Data 

This report is the collective effort of close to 150 researchers, organized into seven committees, working over nearly five years. A multidisciplinary “Design Committee,” with members drawn from industry, environmental groups, government, and universities, identified ten key characteristics of ecosystem condition that are valued by Americans and that, in our judgment, need to be addressed in any credible, balanced and useful report. These ten characteristics describe the physical dimensions of the systems, their chemical and physical conditions, the status of their biological components, and the amounts of goods and services people receive from them (see Figure 3.1). We also decided to report on these indicators for the nation as a whole and for six major ecosystem types that have long been the focus of policy debate, research, management, and monitoring—coasts and oceans, farmlands, forests, freshwaters, grasslands and shrublands, and urban and suburban areas.

Six ecosystem-specific work groups, each with representation from business, environmental, academic, and government institutions, identified between 15 and 20 specific indicators for each system, as well as a set of “core national indicators.” The indicators were selected based on their importance; no indicator was ruled out simply because the data to report on it is not currently available. Each of the ecosystem-specific work groups then carefully examined potential data sources for reporting on each indicator. We used data only if it met high professional standards for integrity and overall quality and allowed us to report on most of the United States, and if there was a reasonable likelihood that the underlying measurements would be repeated over time. Key data gaps became apparent and are identified throughout the report.

Finally, we obtained the required data from the government agencies and private organizations that collect and maintain them. Our primary focus was to present current conditions and to lay the groundwork for future reporting, but wherever possible we sought datasets with records long enough to reveal trends. When they were available, we compared data on current conditions with widely accepted reference points, primarily regulatory and related standards and guidelines, while recognizing that there are judgments involved in setting such standards. In many cases, we also provided data on a regional basis, allowing comparisons between regions.