July 28, 2009
Gulf Dead Zone Shrinks, Intensifies
BY: CaitlinF
Would you like the good news or the bad news first? Personally, I’ve always been a bad-then-good-news person, so here’s the bad: scientists have found that a dead zone, a region of water with very low oxygen levels, in the Gulf of Mexico has a much deeper and thicker level of low-oxygen (hypoxic) water in some parts of the Gulf than normal. The good? That same dead zone is smaller than expected—it is about 3000 square miles instead of the predicted 8000 square miles. Essentially, this dead zone is smaller, but more concentrated in areas. In an article published Monday in The New York Times, Henry Fountain explores the effects of this discovery. While the smaller area means less disruption for marine animals such as shrimp and crab, the organisms in the hypoxic areas were “obviously stressed.” Oxygen levels decrease when nutrients such as nitrogen and phosphorus enter the water, causing an overabundance of algae. The extra algae then sink to the bottom where it is decomposed by bacteria, which use up most of the oxygen in the water. Without any oxygen, fish and other creatures either leave the area or die. The Gulf dead zone is the most notorious dead zone of about 250 areas around the world. Jane Lubchenco, administrator of NOAA, noted, “some progress is being made, but not enough.”