A team of scientists from Texas A&M University, Texas A&M at Galveston, Louisiana State University and NASA recently surveyed the dead zone in the northern Gulf of Mexico and their findings show that the area's water contains lower oxygen levels than expected this time of year.
That could mean the dead zone area could be more severe in 2005 and perhaps cover an even larger area than in previous years, says Steve DiMarco, associate professor in the Department of Oceanography at Texas A&M and leader of the project.
"During January and February of this year, the flow of the Mississippi River was larger than at any time in 2004," DiMarco explains. "That means the stratification levels between the fresh river water and heavier salt water could results in increased hypoxia, which creates the dead zone."
Hypoxia is a term for extremely low levels of oxygen concentrations in water. Hypoxia can result in fish kills and can severely impact other forms of marine life where it is present.
The dead zone area covers about 6,000 square miles in the Gulf.
The dead zone is located along the Louisiana coast where the Mississippi and Atchafalaya Rivers empty into the gulf. The dead zone area typically develops in late spring and early summer following the spring flood stage of the rivers, which bring large amounts of nutrients often in the form of fertilizer into the Gulf of Mexico.
The Mississippi is the largest river in the United States, draining 40 percent of the land area of the country. It also accounts for almost 90 percent of the freshwater runoff into the Gulf of Mexico.