ABSTRACT
In 2001, a task force of federal, state, and tribal representatives—established under the Harmful Algal Bloom and Hypoxia Research and Control Act of 1998—set a goal of reducing the size of the dead zone (the hypoxic region in the northern Gulf of Mexico) from its current size of more than 4.9 million acres (20,000 km2) to below 1.2 million acres (5,000 km2) (U.S. EPA 2001). In its action plan, the task force recognized that to reach that goal, nitrogen loads to the Gulf would have to be reduced by approximately 30 percent. Subsequent modeling analyses (Scavia et al. 2003, 2004; Justic et al. 2003a ,b, 2005) indicate that, considering interannual variability in ocean conditions and potential long-term climate change, nitrogen loads should be reduced even further—in the range of 40 to 50 percent—to reach the task force goal.
