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Three Historic Blowouts 1. Lauren Schenkman Figure Mexico 1979 "CREDIT: NOAA" The decade from 1969 to 1979 witnessed three massive spills from offshore oil wells around the world. Here is how they compare in size and impact. IXTOC 1 The biggest well-related spill was triggered on 3 June 1979, when a lack of drilling mud allowed oil and gas to shoot up through the 3.6-km-deep IXTOC 1 exploratory well, about 80 km offshore in the southern Gulf of Mexico. The initial daily outflow of 30,000 barrels of oil was eventually reduced to 10,000 barrels. The well was finally capped more than 9 months later. Mexico's state-owned oil company, PEMEX, treated the approximately 3.5-million-barrel spill with dispersants. U.S. officials had a 2-month head start to reduce impacts to the Texas coastline. Figure North Sea 1977 "CREDIT: WALLY FONG/AP PHOTO" Ekofisk The first major spill in the North Sea resulted in the release of 202,000 barrels of oil about 250 km off the coast of Norway. The 22 April 1977 blowout caused oil to gush from an open pipe 20 m above the sea surface. The well was capped after a week. Between 30% and 40% of the spill evaporated almost immediately. Rough waters broke up the slick before it reached shore. Figure Santa Barbara 1969 "CREDIT: BETTMANN/CORBIS" Santa Barbara A blown well 1 km below the sea floor and 9 km off the coast of Santa Barbara, California, spewed out a total of 100,000 barrels of oil. The initial eruption occurred on 28 January 1969, and the well was capped by mud and cement on 7 February, but the pressure forced oil through sea floor fissures until December. The oil contaminated 65 km of coastline. At least 3700 birds are known to have died, and commercial fishing in the area was closed until April.

"Nitrogen (N2)-fixing microorganisms (diazotrophs) are an important source of biologically available fixed N in terrestrial and aquatic ecosystems and control the productivity of oligotrophic ocean ecosystems. We found that two major groups of unicellular N2-fixing cyanobacteria (UCYN) have distinct spatial distributions that differ from those of Trichodesmium, the N2-fixing cyanobacterium previously considered to be the most important contributor to open-ocean N2 fixation. The distributions and activity of the two UCYN groups were separated as a function of depth, temperature, and water column density structure along an 8000-kilometer transect in the South Pacific Ocean. UCYN group A can be found at high abundances at substantially higher latitudes and deeper in subsurface ocean waters than Trichodesmium. These findings have implications for the geographic extent and magnitude of basin-scale oceanic N2 fixation rates. "

Isles of Abundance Britain has taken another step toward designating the world's largest marine reserve around the Chagos Islands, a group of 55 coral protrusions in the Indian Ocean. The government announced the end of a 4-month public comment period on 5 March and is expected to reach a final decision by May. The Chagos contain half of the Indian Ocean's remaining healthy reefs. The waters are said to be among the cleanest on Earth, allowing corals to grow in deep water less vulnerable to global warming. The islands are located in the equatorial "tuna belt," which hosts what a Royal Zoological Society of London report called one of the "most exploited, badly enforced fisheries in the world." A total ban on fishing in the 544,000-square-kilometer zone, an area the size of France, would make it an even larger protected area than the current record-holder, the 360,000-km2 Papahanaumokuakea Marine National Monument in the northwestern Hawaiian Islands. The Pew Environment Group has spearheaded a 3-year campaign for creation of a Chagos reserve. It would be "literally an island of abundance in a sea of depletion," says Pew's Jay Nelson. The islands are uninhabited except for the U.S. Navy base on Diego Garcia. Some 1500 Chagossians were deported to Mauritius in the 1970s for military security.