The dead zone in the Gulf of Mexico, a region virtually devoid of oxygen and thus unable to sustain marine life, is an annual phenomenon. Nutrients, including fertilizers, that are carried into the Gulf by rivers are the main culprits in creating the zone. The abundance of nutrients causes algae to grow and absorb all available oxygen.

Scientists are now predicting that the dead zone is likely to be larger than ever this year. As more nitrates than in previous years have been swept into the sea. Ironically one possible cause of the increased nitrate levels is the production of corn for biofuels (ethanol).

The nitrate levels don’t make a record breaking dead zone a certainty. The situation however be changed by an active storm season mixing up the waters and dispersing the concentrated nutrients.

The Gulf of Mexico is not unique in having a dead zone, although it’s an especially large one. The UN warns that dead zones are growing more common, as intensive farming practices spread around the world. If the present trend continues important fish stocks may be in danger because of the dead zones.

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