Great Lakes Observing & Forecasting Systems

Transitioning to Operations NOAA-Supported Statistical Hypoxia Models and Forecasts in the Gulf of Mexico and Chesapeake Bay

Overview and Objectives

The Harmful Algal Bloom and Hypoxia Research and Control Act (HABHRCA) mandates developing scientific tools for managers addressing hypoxia in coastal systems. In response, NOAA supported development of scenario forecast models in many U.S. coastal regions with serious hypoxia problems with the most mature of these efforts being focused in the northern Gulf of Mexico and the Chesapeake Bay. Models are being used in both regions to inform regional management entities of progress toward hypoxia reduction goals. They also play a crucial role in raising public and stakeholder awareness of the hypoxia problems and the actions needed to address them, which is an essential element of a successful management plan. These models for the Northern Gulf of Mexico are also the primary management tool used to set nutrient loading targets to reach the interagency Hypoxia Task Force goal of reducing the size of the hypoxic zone to 5,000 square kilometers. The suite of forecast models currently used to produce the annual Gulf of Mexico dead zone forecast and to support long-term management decisions of the Gulf Hypoxia Task Force, as well as development of statistical models for the Chesapeake Bay, have been the product of competitive research funding from NOAA’s National Centers for Coastal Ocean Science. The main objective of this project is to finalize the transition to NOAA of the models developed, provide training on their operation, and simultaneously ensure that the forecast outputs are produced during the period of transition.

The purpose of this project is to develop and implement a plan for transition to “sustained operations” of an ensemble-based, statistical modeling framework for hypoxia forecasting and assessment in the Gulf of Mexico and Chesapeake Bay that is capable of addressing NOAA’s responsibilities to the Gulf Hypoxia Task Force and regional management entities. The developed system provides a template for application to other regions (e.g., Great Lakes), applications (e.g., living resources impacts, watershed linkages), and capabilities (e.g., coupled modeling platforms, and scenario-based management questions). The 3 main focal areas of activity are outlined below. Activity Area 1: Produce the annual dead zone forecasts for the Gulf of Mexico hypoxic zone size (area and volume) and Chesapeake Bay (anoxic and hypoxic zone volume) in coordination with NOAA. Activity Area 2: Provide technical assistance in coordination with NOAA staff for Gulf of Mexico hypoxia related questions from the Gulf Hypoxia Task Force which are amenable to or can be aided by statistical modeling approaches. Activity Area 3: In coordination with NOAA staff, develop the requirements and conduct the training required for NOAA to maintain an operational scenario forecasting capability to address the management and public information needs related to hypoxia in the Gulf of Mexico and Chesapeake Bay, with expandability to other systems around the U.S. experiencing hypoxia.


Scavia, D. Modeling hypoxia in freshwater and marine coastal environments. Linking watershed biogeochemistry & coastal ecology: Challenges for modeling & environmental Policy. Symposium and Workshop, University of Waterloo, June 16 & 17, 2016

Turner, R.E. Corn-Soy, Landscapes, and the Hypoxia of the Gulf of Mexico. The True Cost of American Agriculture, San Francisco, CA. 15-16 April 2016. Gulf Hypoxia Task Force – Science Approach. Illinois Association of Wastewater Agencies – Mini Conference, Springfield, IL. 24 March 2016.

Testa, J. “Hold Your Breath and Keep Swimming: Advances in our Understanding of the Chesapeake Dead Zone, CBL’s Citizen Science Seminar Series on October 20, 2015

Obenour, D.R., Y. Zhou, D. Scavia, A.M. Michalak. “Mapping and Modeling Hypoxia in Marine and Freshwater Systems.” Coastal and Estuarine Research Federation Conference, Portland, OR, 10 Nov 2015.


• NOAA annual Chesapeake Bay Hypoxia and Anoxia forecast press release ( • NOAA annual Gulf of Mexico Hypoxia ensemble forecast press release (