The broken BP Horizon well is leaking another dangerous substance besides oil: methane gas, at concentrations up to 100,000 times the natural levels. The extremely high volumes of methane are causing anoxic conditions which are killing off the lower segments of the ocean food chain, and threatening the survival of many species of fish. In the Guardian UK:
"In a conference call with reporters, Samantha Joye, a scientist at the University of Georgia who has been studying the effects of the spill at depth, said the ruptured well was producing up to 50% as much methane and other gases as oil. . . Joye said her preliminary findings suggested the high volume of methane coming out of the well could upset the ocean food chain. Such high concentrations, it is feared, would trigger the growth of microbes, which break up the methane, but also gobble up oxygen needed by marine life to survive, driving out other living things."
The release of huge amounts of methane gas in the oceans is every climate scientist's worst nightmare. Methane is 72 times more potent a greenhouse gas than C02. Not only does it speed up global warming, oceanic methane causes anoxic "dead zones" that kill oxygen-breathing sea life, increases ocean acidity and decreases the capacity of the ocean to absorb C02.