Deepwater Horizon Missing Oil Explained
Bad as the April 20, 2010 Deepwater Horizon oil spill into the Gulf of Mexico was, it’s difficult to believe that it could have been even worse.
Eleven lives were lost and over 600 million liters of oil were dumped into the ocean, destroying fisheries and arousing concern that the clean-up might take decades. Friday is the 13th day of an ongoing civil trial in federal court in New Orleans that will help determine how much BP will ultimately pay for clean-up and damages.
In February, BP pleaded guilty to manslaughter charges brought by the US Department of Justice and agreed to pay $4 billion for the 11 wrongful deaths.
Despite the scale of the disaster, the Gulf of Mexico clean-up efforts got some unexpected help from Mother Nature. Natural petroleum-eating microbes went to work in the warm waters, setting out on a five month feeding frenzy that sucked up a reported 200,000 tons of oil. About 40% of the spilled oil and natural gas was consumed before the microbes started to falter.
According to a recent article by Mark Schrope in the journal Nature, most of the oil was gone within months. But where did it all go? US authorities have never been able to explain where about one-quarter of the spilled oil ended up.
At the January Gulf of Mexico Oil Spill and Ecosystem Science Conference in New Orleans, several scientists speculated that the missing oil mixed with deep ocean sediments. The sticky oil may have clumped together plankton and other material normally found on the ocean’s surface, causing it to become so heavy that it rained down to the bottom of the ocean in what they called “a dirty blizzard.”
Oceanographer David Hollander compared the layer of oily gunk to a dirty bathtub and told Schrope that up to 30% of the clumped oil has collected in a layer on the bottom of the ocean. That’s oil that was never consumed by the petroleum-eating microbes and could conceivably contaminate fish that feed in deep waters.
If Nature’s theory is right, there is still Deepwater Horizon spilled oil down there that could affect future generations.
[photo courtesy NASA/Goddard Space Center]