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EPA's Report on the Environment



About the ROE

What is the ROE?

To accomplish its mission, EPA must pay close attention to trends in the condition of the nation's air, water, and land, and to the associated trends in human exposure and health and ecological condition. The ROE compiles the most reliable indicators currently available to help answer 23 questions that EPA believes are of critical importance to its mission and the nation's environment. The ROE focuses on trends within the United States, even when those trends might be affected by sources and conditions outside U.S. borders. Data on environmental trends:

  • Allow EPA and the public to assess whether the Agency is succeeding in its overall mission to protect human health and the environment.
  • Provide valuable input to EPA in developing its strategic outlook and priorities.

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What's in the ROE?

This version of the ROE presents 85 indicators, all of which were peer-reviewed to meet high standards for accuracy, representativeness, and reliability. The indicators are supported by data gathered from federal and state agencies and non-governmental organizations. Each indicator comprises:

  • A graphic showing the trend in indicator data over time, or a national baseline when data are not yet available to show a trend. Note: In the ROE, the word “trend” simply means the direction of change, and does not imply statistical significance.
  • Text describing:
    • What the indicator covers.
    • What the data show.
    • Any limitations that generate uncertainty in the trend characterized by the indicator.
    • Data sources and references.
  • Technical documentation.

The ROE does not propose actions to reduce data limitations or fill gaps, nor does it analyze the costs and benefits of doing so.

The ROE is a dynamic resource. EPA adds new indicators to better answer the ROE questions as suitable data become available from federal, state, and non-governmental organizations. EPA also updates the ROE indicators on a rolling basis to provide the latest available data. For each indicator, the update frequency depends on the frequency with which new data become available. Some indicators are updated annually; others may only be updated every few years. For some indicators, data do not become available to the ROE until after the data collection program has processed samples and compiled the results. This can create a time lag between data collection and update publication.

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What are the “ROE questions”?

EPA has identified 23 areas where trend information is critical for the Agency to stay adequately informed about the condition of the environment and human health. In the ROE, these areas are listed as questions. The ROE presents indicators that help EPA address these questions:

Air

Water

Land

Human Exposure and Health

Ecological Condition

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What is an ROE indicator?

ROE indicators are simple measures that track the state of the environment and human health over time. They are based primarily on measurements of physical or biological conditions within a clearly defined geographic area.

To maintain a high level of scientific integrity and consistency among the indicators used in the ROE, EPA established an explicit definition and six criteria for ROE indicators. The criteria are based in part on EPA's Information Quality Guidelines (PDF) (61 pp, 321K), which cover important information that EPA provides to the public. All ROE indicators were peer-reviewed against this definition and criteria to ensure that they are useful, objective, transparent, and scientifically reliable.

Indicator Definition and Criteria

Indicator definition: An ROE indicator is a numerical value derived from actual measurements* of a driver, stressor, state or ambient condition, exposure, or human health or ecological condition over a specified geographic domain, whose trends over time represent or draw attention to underlying trends in the condition of the environment.

Indicator criteria:

  • The indicator is useful. It answers (or makes an important contribution to answering) a question in the ROE.
  • The indicator is objective. It is developed and presented in an accurate, clear, complete, and unbiased manner.
  • The indicator is transparent and reproducible. The specific data used and the specific assumptions, analytic methods, and statistical procedures employed are clearly stated.
  • The underlying data are characterized by sound collection methodologies, data management systems to protect their integrity, and quality assurance procedures.
  • Data are available to describe changes or trends, and the latest available data are timely.
  • The data are comparable across time and space, and representative of the target population. Trends depicted in this indicator accurately represent the underlying trends in the target population.

*There is some flexibility in this criterion. For example, the air emissions indicators, solid waste indicator, and sustainability indicators have several components that are based on estimation or partial estimation methodologies applied to the best available data.

The ROE excludes:

  • Administrative indicators such as permits issued, regulations promulgated, and enforcement actions undertaken.
  • Indicators based on results predicted by environmental fate and transport models or predicted risks to people or ecological systems.
  • One-time studies unless they serve as baselines for future trends that can be tracked over time.

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How do ROE indicators relate to environmental issues of concern to EPA?

Since the concept of sustainability is based on the fundamental interdependence between human and natural systems, the ROE adapted a systems-based framework that illustrates the linkages among the three dimensions (environment, society, economy) of sustainability. The ROE uses this conceptual framework and associated diagrams to show how ROE indicators relate to six issues of concern to EPA, and how these particular issues and the ROE themes relate to each other in the context of sustainability. These six environmental issues—acid deposition, coastal hypoxia, fish mercury contamination, nutrient impacts, tropospheric ozone, and wetlands loss—were chosen because they are examples of cross-thematic problems, as presented in EPA's Strategic Plan. For each issue, the ROE:

  • Gives an overview of how the issue fits into the framework.
  • Identifies the key system attributes (activities, sources, effects, etc.) and shows how they are interrelated.
  • Shows which ROE indicators are relevant.

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What's new in the ROE?

The ROE was first published, in hard-copy format, in 2003 and was substantially revised in 2008. This, the third version of the ROE, is entirely online. After receiving public comment and external peer review, the ROE has been revised to include six new indicators and many new features such as:

  • Interactive graphics. Interactive tools allow you to customize graphical displays and view certain indicators in zoomable map form.
  • Statistical information. The ROE presents statistical information for indicators where such information is readily available.
  • Search the ROE. You can search the ROE website using the search box at the top right of every ROE page.
  • Regional and state trends. Here you can explore, for certain ROE indicators, environmental trends at regional and state levels and related information relevant to where you live.
  • What you can do. Visit this section to learn what you can do to help protect the environment and your health, and foster a sustainable future.
  • Sustainability. In response to growing U.S. and international concern, the ROE now introduces sustainability using a systems-based framework to illustrate how ROE indicators can be integrated and further developed to support sustainability-based environmental protection.

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