Earth 

Mississippi Dead Zone

Recent reports indicate that the large region of low oxygen water often referred to as the 'Dead Zone' has spread across nearly 5,800 square miles of the Gulf of Mexico again in what appears to be an annual event. NASA satellites monitor the health of the oceans and spots the conditions that lead to a dead zone. These images show how ocean color changes from winter to summer in the Gulf of Mexico. Summertime satellite observations of ocean color from MODIS Aqua show highly turbid waters which may include large blooms of phytoplankton extending from the mouth of the Mississippi River all the way to the Texas coast. When these blooms die and sink to the bottom, bacterial decomposition strips oxygen from the surrounding water, creating an environment very difficult for marine life to survive in. Reds and oranges represent high concentrations of phytoplankton and river sediment. The National Oceanic and Atmospheric Administration (NOAA) ships measured low oxygen water in the same location as the highly turbid water in the satellite images. Most studies indicate that fertilizers and runoff from human sources is one of the major stresses impacting coastal ecosystems. In the third image using NOAA data, reds and oranges represent low oxygen concentrations.


For More Information

http://www.gsfc.nasa.gov/topstory/2004/0810deadzone.html


Visualization Credits

Greg Shirah (NASA/GSFC): Lead Animator
Gene Feldman (NASA/GSFC): Scientist
Please give credit for this item to:
NASA/Goddard Space Flight Center Scientific Visualization Studio

Short URL to share this page:
http://svs.gsfc.nasa.gov/goto?2979

Data Used:
Aqua/MODIS winter: 2003/02/10 - 2004/02/17 summer: 2002/07/12 - 2004/07/18

Keywords:
SVS >> Phytoplankton
SVS >> Population growth
SVS >> Urbanization
SVS >> For Educators
SVS >> Dynamics of Populations
SVS >> Photosynthesis
SVS >> Location >> Mississippi
SVS >> Location >> Gulf of Mexico
SVS >> Hydrosphere >> Oceans >> Dead Zone
SVS >> Hydrosphere >> Oceans >> Anomalies
NASA Science >> Earth