What the spill will kill
Giant plumes of crude oil mixed with methane are sweeping the ocean depths with devastating consequences. ‘I’m not too worried about oil on the surface,’ says one scientist. ‘It’s the things we don’t see that worry me the most.’ 
By Sharon Begley, with Ian Yarett in New York and Daniel Stone in Washington
June 06, 2010 It was in mid-May that independent scientists—not any of the officials or researchers working for any of the government agencies on scene at the Deepwater Horizon disaster, let alone BP—first detected the vast underwater plumes of crude oil spreading like Medusa’s locks from the out-of-control gusher in the Gulf of Mexico. BP immediately dismissed the reports, and in late May CEO Tony Hayward flatly declared “there aren’t any plumes,” stopping just short of accusing the scientists of misconduct. Federal officials called the scientists’ claim “misleading, premature and, in some cases, inaccurate.” Moreover, continued a statement from the National Oceanic and Atmospheric Administration, any oxygen depletion in the surrounding waters due to plumes is not “a source of concern at this time,” and critics blaming dispersants for the plumes had “no information” to stand on. NOAA administrator Jane Lubchenco, a respected oceanographer when President Obama tapped her to lead the agency, insists there are no plumes, only “anomalies”—though last week she acknowledged the possibility of oil beneath the surface. Now it is increasingly clear that the initial reports of undersea oil were right, that life-giving oxygen in the water column is indeed being depleted, and that unless the laws of chemistry have been repealed, dispersants are likely worsening the tentacles of undersea crude. What might have been just another oil spill—albeit a bad one—has been transformed into something unprecedented. Even if the containment dome lowered into place late last week continues to siphon off some of the leaking crude, the Deepwater Horizon disaster will enter the record books not for how much but for where: an enormous release of crude oil not only onto vulnerable shorelines and fragile marshes but into the largely unexplored depths of the sea. The consequences for the delicate balance of existence in the vulnerable ecosystems of the gulf, and for the vast cycles of nature that sustain life there and beyond, are as incalculable as they are potentially devastating. “I’m not too worried about oil on the surface,” says chemist Ed Overton of Louisiana State University. “It’s going to cause very substantial and noticeable damage—marsh loss and coastal erosion and impact on fisheries, dead birds, dead turtles—but we’ll know what that is. It’s the things we don’t see that worry me the most. What happens if you wipe out all those jellyfish down there? We don’t know what their role is in the environment. But Mother Nature put them there for a reason,” and many are in the plumes’ paths. Their presence has blown to smithereens the cliché that oil floats on water. That correctly describes what happens when pure crude spills into the sea from a well in shallow water or a tanker at the surface, as happened with the Exxon Valdez. But when a gusher is 5,000 feet down, consists of a mix of crude oil and dissolved methane, and is being disgorged under tremendous pressure and temperature, studies predict that the physical and chemical properties of the spill will undergo an ugly alchemy. “The dispersants are changing the chemistry and physics of the oil,” says biological oceanographer Ajit Subramaniam of Columbia University’s Lamont-Doherty Earth Observatory. “They are creating microlayers of oil that are being carried by the deep currents.” Even without dispersants, the crude gets broken into zillions of droplets suspended in the water column and corralled there, prevented from rising to the surface. The result is the undersea plumes that oceanographer Samantha Joye of the University of Georgia and colleagues first detected from the research vessel Pelican three weeks after the blowout. Despite years of research showing that undersea oil might form such plumes, BP’s Hayward insists it cannot. “Oil floats!” he repeatedly says. …
