The Gulf Dead Zone is Growing Larger Than Anticipated

Researchers who annually measure the oxygen deprived "dead zone" in the Gulf of Mexico have recently found that this year it is nearly as large as the state of Connecticut. That's three times larger than an anticipated 2015 target size.

The Gulf Dead Zone is a huge swath of the Gulf of Mexico just west of the Mississippi River Delta that is nearly devoid of oxygen and proportionally saturated with nitrogen and phosphorus pollution.

Containing barely any oxygen, these regions become absent of "commercial quantities" of shrimp and fish, according to the Louisiana Universities Marine Consortium (LUMC). A LUMC assessment of the Dead Zone this year showed that it has grown to an average 5,500 square miles over the last five years. And while this growth falls into recent models based on current nitrogen measurements, it is still three times larger than the environmental target set by a federal task force in 2001, dedicated to keeping the zone controlled.

So what exactly makes a dead zone? According to the LUMC and the NOAA, dead zones are created by hypoxia (oxygenic depletion) and occur naturally all over the world - including in the fjords, deep basins and near intense upwelling systems. However, research has found that their occurrence in shallow coastal regions has increased in the last few decades as the result of human activities. In fact, it is thought that the Gulf Dead Zone is the second largest unnatural (or unnaturally augmented) dead zone in the world, with pollution coming from the Mississippi Delta bullying oxygen out of this environment.

"While it is known that Louisiana is not one of the top contributors of dead zone-causing pollution, that is where the biggest impacts are felt," Matt Rota, Senior Policy Director for the Gulf Restoration Network, said in a recent statement.

"Currently we are seeing the impacts of nitrogen and phosphorous pollution, not only off the Louisiana coast, but throughout the country," he added. "From undrinkable water in Toledo to a 4,000 square mile toxic Red Tide looming off the coast of Florida, it is obvious that current efforts to reduce harmful nitrogen and phosphorous pollution are not adequate."

Rota associates unnatural dead zones with the oxygen deprivation caused by some harmful algae blooms.

However, despite initiatives launched by conservation groups and the Environmental Protection Agency, it is important to note that Louisiana legislation has recently tried to remove the state's Gulf Waters from their "impaired waters list," citing contradictory scientific work that claims that, at least in part, the Gulf Dead Zone may be a natural occurrence.