ENVIRONMENT | Protecting our natural resources
22 May 2008
New Report Describes State of U.S. Environment, Human Health
Environmental agency evaluates national trends in air, water, ecosystems
Washington -- In a report released May 20, the U.S. Environmental Protection Agency (EPA) asks and answers 23 questions about trends in the condition of the nation’s air, water and land, and associated trends in ecological systems and human health in the United States.
The 366-page Report on the Environment offers a snapshot of the state of the U.S. environment and uses a range of indicators to sort out the complexity inherent in measuring interactions among pollutants, environmental factors, ecological systems and people.
“This report is extremely important to EPA,” Peter Preuss, director of the National Center for Environmental Assessment in the EPA Office of Research and Development, which created the report, said during a May 20 briefing. “These indicators directly help us in two ways -- one is to see where we are with respect to those kinds of goals, and the second is to help us plan for the future.”
The report comes at a time when nations around the world are struggling to determine the effects of environmental stresses, like the changing climate, on people and natural resources. EPA’s Report on the Environment could lead to the development of new indicators, new monitoring strategies and new programs and policies that governments and scientists everywhere can apply to their own circumstances.
EPA compiled the most reliable indicators available to answer 23 important questions at the core of EPA’s mission to protect human health and the environment, said George Gray, assistant administrator in the Office of Research and Development. It also identifies limitations of the indicators and gaps where indicators do not yet exist.
“In 2001,” Gray added, “EPA embarked on a bold initiative to assemble for the first time indicators of national conditions that are important to its mission. EPA first presented this information in a 2003 draft report on the environment. Since then, EPA has revised and refined its report in response to feedback we’ve received from our science advisory board and stakeholders, and we’ve updated the indicators to reflect the very latest data.”
INDICATORS
Indicators are measures of specific events or conditions from which broader trends can be extrapolated. For instance, data on the state of health of people in a defined population can show what is happening in the broader population. Every indicator and the report itself were subjected individually to review by scientists outside the EPA.
The report is in print and freely available on the Internet. The online report will be continuously revised as new data become available; a new printed edition of the report will be published every few years.
“The really important aspect of this report is that it’s built on questions,” Preuss said. “Most indicator reports are an agglomeration of indicators that are put together to see if they can tell a story. We took the opposite approach. We asked, what are the important questions for the Environmental Protection Agency?”
Key questions include:
• What are the trends in greenhouse gas emissions and concentrations?
• What are the trends in the quality of drinking water and their effects on human health?
• What are the trends in contaminated land and their effects on human health and the environment?
• What are the trends in human disease and conditions for which environmental contaminants may be a risk factor?
• What are the trends in the extent and distribution of the nation’s ecological systems?
Using the report’s greenhouse gas question as an example, trends in greenhouse gas emissions and concentrations were taken from two indicators -- the U.S. Greenhouse Gas Emissions and the Greenhouse Gas Concentrations databases.
The greenhouse gas indicator spans 1990 to 2005 and contains data from EPA’s Inventory of U.S. Greenhouse Gas Emissions and Sinks (places where greenhouse gases can be stored, such as trees and soils). This database tracks greenhouse gas emissions directly attributable to human activities and greenhouse gas sinks.
The Greenhouse Gas Concentrations indicator summarizes direct measurements of air concentrations from the last 50 years and observations from earlier times based on chemical analyses of air bubbles found in ice core samples.
TRENDS
For greenhouse gas trends, the indicators show that for several greenhouse gases -- such as carbon dioxide, methane, nitrous oxide and certain synthetic chemicals -- the nation’s estimated combined emissions that are directly attributable to human activity increased 16 percent between 1990 and 2005.
Emission sources occur in several sectors of the U.S. economy, with the highest contribution -- and the greatest recent growth -- attributed to energy use, mainly electricity generation and transportation.
“Taken together,” the report reads, “the well-documented long-term trends in concentrations of greenhouse gases, along with corresponding increases in emissions from anthropogenic [human-generated] sources, show that human activity is causing increased concentrations of greenhouse gases in the Earth’s atmosphere -- a finding echoed in many prominent reviews on the science of climate change.”
The section also outlines limitations of and gaps in the indicators for each section.
“This is a science report,” Preuss said. “This is a description of what is happening, it’s not predicting what’s going to happen, it’s not assessing what is likely to happen. It’s as accurate a representation as we can get of what is going on in the environment today.
“With this report, we have a sense of where we are,” Preuss added. “With the goals we have set ourselves, we have a sense of where we want to be. As we develop the path to get to where we want to be, this report will play a significant role. All of us in the agency who have worked on this, and there are several hundred, see a great deal of promise in this report.”
More information on the process and the full text of the Report on the Environment are available on the EPA Web site.
See also “U.S. Agency Charged with Protecting, Enhancing Environment.”
