Dr. Donald Boesch - Gulf of Mexico Hypoxia Activities

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Initiation of Research

While serving as Executive Director of the Louisiana Universities Marine Consortium during the 1980s I helped initiate the first systematic studies of the distribution, dynamics and causes of hypoxia (severe depletion of dissolved oxygen) in bottom waters of the inner continental shelf off Louisiana and Texas. Extensive subsequent research has evaluated the distribution and dynamics and the human role in exacerbating hypoxia has received much public attention, earning entry into Wikipedia as the Dead Zone.

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Integrated Assessment (12.6 MB)

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Action Plan (6.4 MB)

Integrated Assessment 2000

 A congressionally mandated [section 604(a) and (b) of Public Law 105-383] Integrated Assessment of the causes, consequences and potential solutions for Gulf hypoxia was conducted under the auspices of the Committee on Environment and Natural Resources of the President's National Science and Technical Council.

I served as on the Editorial Board for the peer review of the six Hypoxia Assessment Reports that were the foundation for the Integrated Assessment. In particular, I served as co-editor of the reports on characterization of hypoxia (Topic 1), ecological and economic consequences (Topic 3), and effects of reducing nutrient loads (Topic 4). Essentially, these assessments demonstrated that intense and recurrent hypoxia is a relatively recent phenomenon related to the increased delivery of nutrients by the Mississippi-Atchafalaya river system, mainly from agricultural sources in the upper part of the catchment.

The Integrated Assessment led to an Action Plan, endorsed in 2001 by the Federal Government and states and tribes within the basin, which has as a goal reducing the average areal extent of the Gulf of Mexico hypoxic zone to less than 5,000 square kilometers by 2015 by reducing the discharge of nitrogen to the Gulf through implementation of specific, practical, and cost-effective voluntary actions.

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As is the case for climate change science, there are contrarians, often associated with the agricultural sector, who have criticized the basis for conclusions linking agricultural nutrient sources and hypoxia. As is the case with climate science, however, there are a few agricultural scientists, hydrologists, or oceanographers who have taken serious exception with the findings of the Integrated Assessment. I have contributed to two papers offering rebuttals to the criticisms of some ocean scientists:

Continental shelf hypoxia: Some compelling answers

Nutrient enrichment drives Gulf of Mexico hypoxia with electronic supplement.

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Reassessment 2007

The 2001 Action Plan called for an assessment by December 2005 and every five years thereafter of "the nutrient load reductions achieved and the response of the hypoxic zone, water quality throughout the Basin, and economic and social effects." Based on these assessments, the Task Force responsible for implementing the Action Plan would "determine appropriate actions to continue to implement this strategy or, if necessary, revise the strategy." The Task Force undertook a Reassessment during 2007-2008. The Reassessment has included various symposia, workshops and evaluation by the EPA Science Advisory Board. The SAB convened a Hypoxia Advisory Panel (HAP) tasked to "conduct an evaluation of the complex scientific and technical issues that affect the causes, magnitude and duration of the hypoxic zone...as well as the priority and feasibility of management and control options in the Mississippi River Basin and Gulf to reduce it."  I contributed extensive perspectives to this panel, which in 2007 published its final report Hypoxia in the Northern Gulf of Mexico: An update by the EPA Science Advisory Board.

The Final 2008 Action Plan is here.

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