Gulf Dead Zone Growing Irrespective of Oil Spill

With every disaster come the rumors of more disaster to come. I remember Hurricane Andrew, 1992, and the silliness that followed it such as: thousands of dead are being taken out in body bags by the military. They are being loaded secretly in Home Depot trucks. Then there was “another hurricane is due within days” rumor and the government [of course] is keeping it quiet so as to avoid panic. Millions are expected to die.

Remember all of the crazy rumors immediately following the 9/11 attacks?

Nothing has changed following the Gulf oil spill. Similar nonsense is being bandied about, especially on the social networks such as FaceBook, MySpace, blogs and etc. by the “sky is falling” folk who say the oil spill will be the cause of huge fireballs that will destroy coastal cities to the most laughable: the extinction of the human species. Naturally there are the equally silly but always inevitable “the government is secretly responsible and is covering up for BP” claims. Among these highly exaggerated and almost always ridiculous assertions is the “dead zone because of the oil” theory. Well the fact is that there has been a dead zone in the Gulf since 2001. It continues to grow and has nothing to do with oil. Read this story and tell me what you think:

University of Michigan aquatic ecologist Donald Scavia and his colleagues say this year’s Gulf of Mexico “dead zone” is expected to be larger than average, continuing a decades-long trend that threatens the health of a $659 million fishery. The 2010 forecast, released by the U.S. National Oceanic and Atmospheric Administration (NOAA), calls for a Gulf dead zone of between 6,500 and 7,800 square miles, an area roughly the size of Lake Ontario.

The most likely scenario, according to Scavia, is a Gulf dead zone of 6,564 square miles, which would make it the Gulf’s 10th-largest oxygen-starved, or hypoxic, region on record. The average size over the past five years was about 6,000 square miles. It is unclear what impact, if any, the Deepwater Horizon oil spill will have on the size of this year’s Gulf dead zone because numerous factors are at work, the researchers say. “We’re not certain how this will play out. But one fact is clear: The combination of summer hypoxia and toxic-oil impacts on mortality, spawning and recruitment is a one-two punch that could seriously diminish valuable Gulf commercial and recreational fisheries,” said Scavia, Special Counsel to the U-M President for Sustainability, director of the Graham Sustainability Institute, and a professor at the School of Natural Resources and Environment. Farmland runoff containing fertilizers and livestock waste — some of it from as far away as the Corn Belt — is the main source of the nitrogen and phosphorus that cause the annual Gulf of Mexico hypoxia zone. Each year in late spring and summer, these nutrients flow down the Mississippi River and into the Gulf, fueling explosive algae blooms there. When the algae die and sink, bottom-dwelling bacteria decompose the organic matter, consuming oxygen in the process. The result is an oxygen-starved region in bottom and near-bottom waters: the dead zone. This year, the situation is complicated by uncertainties related to the Gulf oil spill. If sufficient oil reaches the area typically subject to summer hypoxia, the size of this summer’s Gulf dead zone could increase for two reasons: microbial breakdown of oil — which consumes oxygen — and the oil’s potential to reduce diffusion of oxygen from the air into the water, the process that normally replenishes oxygen levels in the water column, Scavia said. On the other hand, the presence of oil could restrict the growth of hypoxia-fueling algae, helping to limit the size of the Gulf dead zone.

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