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11-19-07 Science Advisory Board (SAB) Hypoxia Panel Draft Advisory Report
-- Do Not Cite or Quote --
This Working Draft is made available for review and approval by the chartered Science Advisory Board. This Draft does not represent EPA policy.
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON D.C. 20460
OFFICE OF THE ADMINISTRATOR
EPA SCIENCE ADVISORY BOARD
Honorable Stephen L. Johnson
U.S. Environmental Protection Agency
1200 Pennsylvania Avenue, N.W.
Washington, D.C. 20460
Subject: Hypoxia in the Northern Gulf of Mexico: An Update
by the EPA Science Advisory Board
Dear Administrator Johnson:
Over a year ago, the EPA Office of Water (OW) asked the Science Advisory Board (SAB) to evaluate the most recent science on the hypoxic zone in the Gulf of Mexico as well as potential options for reducing the size of the zone. The hypoxic zone, an area of low dissolved oxygen that cannot support most marine life, has been documented in the Gulf of Mexico since 1985 and was most recently measured at 20,500 km2, an area approximately the size of New Jersey. The SAB was asked to address the science that has emerged since the 2000 publication of An Integrated Assessment: Hypoxia in the Northern Gulf of Mexico (Integrated Assessment), the seminal study by the Committee on Environment and Natural Resources that served as the basis for activities coordinated by the Mississippi River/Gulf of Mexico Watershed Nutrient Task Force. The SAB was also asked to address the most recent science on water quality in the Mississippi Atchafalaya River basin, an area of 31 States and Tribes that drains approximately 40% of the contiguous United States. Further, the SAB was asked to discuss options for reducing hypoxia in terms of cost, feasibility and social welfare. To address this question, the SAB found it necessary to discuss recent research on water quality as well as research on policy options, in particular, those policies that create economic incentives.
Following OW’s request, the Science Advisory Board Staff Office convened an expert panel under the auspices of the chartered SAB. This SAB Panel consists of 21 distinguished scientists from academia, industry and government agencies with expertise in the fields of oceanography, ecology, agronomy, agricultural engineering, economics and other fields. Over the past year, the SAB Panel held numerous public meetings and considered information from invited speakers as well as over 60 sets of public comments in the development of this report.
In issuing the attached report, the SAB reaffirms the major finding of the Integrated Assessment, namely that contemporary changes in the hypoxic area in the northern Gulf of Mexico are primarily related to nutrient loads from the Mississippi Atchafalaya River basin. To reduce the size of the hypoxic zone, the SAB finds that a dual nutrient strategy is needed, targeting at least a 45% reduction in both riverine total nitrogen flux and riverine total phosphorus flux. The SAB offers these as initial targets while stressing the importance of moving in a directionally correct fashion then adjusting policy on the basis of lessons learned and changed conditions. Climate change will likely contribute to changing conditions. A number of studies have suggested that climate change will create conditions where larger nutrient reductions, e.g., 50 – 60% for nitrogen, would be required to reduce the size of the hypoxic zone. An adaptive management approach, coupling nutrient reductions with continuous monitoring and evaluation, can provide valuable lessons to improve future decisions.
The SAB was asked to comment on the Task Force’s goal of reducing the size of the hypoxic zone to 5,000 km2 by 2015. Although the 5,000 km2 target remains a reasonable endpoint for continued use in an adaptive management context; it may no longer be possible to achieve this goal by 2015. Accordingly, it is even more important to proceed in a directionally correct fashion to manage factors affecting hypoxia than to wait for greater precision in setting the goal for the size of the zone.
The SAB underscores that in considering management strategies to reduce Gulf hypoxia, EPA should consider the many benefits of nutrient reduction in the Mississippi Atchafalaya River basin. Such “co-benefits” include improved groundwater and surface water quality, wildlife and biodiversity, recreation, soil quality, greenhouse gas reduction and carbon sequestration. In many cases, co-benefits may exceed the benefits of hypoxia reduction.
Finally, to reduce hypoxia in the Gulf, a systems view, looking at all sources and effects, is needed. The SAB urges the Agency to consider its options with respect to both non-point and point sources. Non-point sources have long been acknowledged as the primary source of nutrient loadings, however the SAB finds point sources are a more significant contributor than previously thought. Atmospheric deposition of nitrogen is also playing a role in hypoxia. In addition, it may be necessary to confront the conflicts between hypoxia reduction as a goal on the one hand and incentives provided by current agricultural and energy policy on the other. Some aspects of current agricultural and energy policies are providing incentives that contribute to greater nutrient loads now and in the future. The SAB recognizes that if agricultural, environmental, and energy policies are to be aligned to support hypoxia reduction, cooperation across a broad spectrum of interests, including the highest levels of government, would be required. We note that regulatory options under the Clean Water Act, an area within EPA’s purview, are addressed by the National Academy of Sciences (NAS) in its recent study, the “Mississippi River and the Clean Water Act.” As pointed out by the NAS, EPA has regulatory authority under the Clean Water Act to address watershed wide issues.
The Executive Summary in the attached Advisory highlights the SAB’s findings and recommendations with more detailed science presented in the main body of the report. We appreciate the opportunity to provide advice on this important and timely topic and look forward to receiving your response.
Dr. M. Granger Morgan, Chair Dr. Virginia Dale, Chair
Science Advisory Board SAB Hypoxia Advisory Panel
This report has been written as part of the activities of the EPA Science Advisory Board, a public advisory committee providing extramural scientific information and advice to the Administrator and other officials of the Environmental Protection Agency. The SAB is structured to provide balanced, expert assessment of scientific matters related to problems facing the Agency. This report has not been reviewed for approval by the Agency and, hence, the contents of this report do not necessarily represent the views and policies of the Environmental Protection Agency, nor of other agencies in the Executive Branch of the federal government. Mention of trade names or commercial products do not constitute a recommendation for use. Reports of the EPA SAB are posted at: http://www.epa.gov/sab.
EPA’s Science Advisory Board Hypoxia Advisory Panel would like to acknowledge many individuals who provided their scientific perspectives for the Panel’s consideration in the development of this report.
Invited Technical Reviewers:
Science Advisory Board
Hypoxia Advisory Panel
U.S. Environmental Protection Agency
Dr. Virginia Dale, Corporate Fellow, Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN
Dr. Thomas Bianchi, Professor, Oceanography, Geosciences, Texas A&M University, College Station, TX
Dr. Alan Blumberg, Professor, Civil, Environmental and Ocean Engineering, Stevens Institute of Technology, Hoboken, NJ
Dr. Walter Boynton, Professor, Chesapeake Biological Laboratory, Center for Environmental Science, University of Maryland, Solomons, MD
Dr. Daniel Joseph Conley, Professor, Marie Curie Chair, GeoBiosphere Centre, Department of Geology, Lund University, Lund, Sweden
Dr. William Crumpton, Associate Professor & Coordinator of Environmental Programs, Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA
Dr. Mark David, Professor, Natural Resources & Environmental Sciences, University of Illinois, Urbana, IL
Dr. Denis Gilbert, Research Scientist, Ocean and Environment Science Branch, Maurice-Lamontagne Institute, Department of Fisheries and Oceans Canada, Mont-Joli, Quebec, Canada
Dr. Robert W. Howarth, David R. Atkinson Professor, Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY
Dr. Catherine Kling, Professor, Department of Economics, Iowa State University, Ames, IA
Dr. Richard Lowrance, Research Ecologist, Southeast Watershed, Agricultural Research Service, USDA, Tifton, GA
Dr. Kyle Mankin, Associate Professor, Biological and Agricultural Engineering, Kansas State University, Manhattan, KS
Dr. Judith L. Meyer, Distinguished Research Professor Emeritus, Institute of Ecology, University of Georgia, Athens, GA
Dr. James Opaluch, Professor, Department of Environmental and Natural Resource Economics, College of the Environment and Life Sciences, University of Rhode Island, Kingston, RI
Dr. Hans Paerl, Professor of Marine and Environmental Sciences, Institute of Marine Sciences, University of North Carolina, Chapel Hill, Morehead City, NC
Dr. Kenneth Reckhow, Professor and Chair, Environmental Science & Policy, Nicholas School, Duke University, Durham, NC
Dr. James Sanders, Director, Skidaway Institute of Oceanography, Savannah, GA
Dr. Andrew N. Sharpley, Research Soil Scientist, Department of Crop, Soil and Environmental Sciences, University of Arkansas, Fayetteville, AR
Dr. Thomas W. Simpson, Professor and Coordinator, Chesapeake Bay Programs, College of Agriculture and Natural Resources, University of Maryland, College Park, MD
Dr. Clifford Snyder, Nitrogen Program Director, International Plant Nutrition Institute, Conway, AR
Dr. Donelson Wright, Chancellor Professor Emeritus, School of Marine Science, Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA
SCIENCE ADVISORY BOARD STAFF
Dr. Holly Stallworth, Designated Federal Officer, EPA Science Advisory Board Staff Office, Washington, D.C.
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