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  2. Mississippi River/Gulf of America Hypoxia Task Force
  3. Tracking Progress

Northern Gulf of America Hypoxic Zone

Background

Source: Rabalais and Turner 2019

In late spring each year, the National Oceanic and Atmospheric Administration (NOAA) releases an estimate of the size of the hypoxic zone for the summer. This forecast predicts the size of the zone using an ensemble of four nitrogen-focused models that consider USGS springtime nitrogen loadings to the Gulf. Later in the summer (typically late July), NOAA supports an annual cruise to physically measure the extent of the zone. This graphic illustrates the frequency of bottom-water hypoxia measured from 1985 to 2014, presenting where hypoxia is more prevalent in the Gulf of America.

Information about the size of the hypoxic zone can be obtained from:

  • NOAA's Gulf of America Hypoxia Watch
  • LUMCON, which is supported by NOAA's Northern Gulf of America Ecosystems & Hypoxia Assessment (NGOMEX)

NOAA's Gulf of America Hypoxia Watch evolved as a cooperative project among NOAA's National Marine Fisheries Service (NMFS), the National Coastal Data Development Center (NCDDC), and the CoastWatch - Caribbean/Gulf of America - Regional Node. The objective of Hypoxia Watch is to develop new near-real time data and map products using shipboard measurements of bottom-dissolved oxygen and disseminate them over the Internet. Access measurements taken from 2001 to the current season.

Annual Forecasts and Measurements

Explore annual measurements and forecasts of the Northern Gulf of America supported by NOAA and LUMCON.

Mississippi River/Gulf of America Hypoxia Task Force

  • Background
    • Current Members
    • History of the HTF
    • Partnerships
    • Related Legislation
  • Goals and Implementation
    • Action Plans and Goal Framework
    • Federal Strategies
    • Implementation
  • Tracking Progress
    • Task Force Success Stories
    • Hypoxic Zone Size
    • Point Source Reports
    • Nonpoint Source Report
    • Reports to Congress
    • Tracking Progress Overview
  • HTF Activities
    • Task Force Newsletters
    • Nutrient Reduction Strategies
    • Task Force Workgroups
    • Recent/Upcoming Task Force Meetings
    • Past Task Force Meetings
  • Resources
    • Gulf Hypoxia Program
    • Task Force Studies/Reports
  • Science of Hypoxia
    • Hypoxia 101
    • The MARB
    • Nutrient Pollution
    • Additional Task Force Resources
Contact Us About the Mississippi River/Gulf of America Hypoxia Task Force
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on February 5, 2025
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