“Invisible oil” from BP’s horrific Deepwater Horizon catastrophe carried an even bigger, more damaging environmental footprint across the Gulf of Mexico than originally reported, according to new research published as the tenth anniversary of the epic oil spill approaches this April.
The study, published earlier this month in the journal Science, “shows that a significant amount of oil and its toxic footprint moved beyond fishery closures where it was thought to be contained and escaped detection by satellites as it flowed near the Texas shore, west Florida shore, and within a loop current that carries Gulf water around Florida’s southern tip up toward Miami,” the Washington Post reports.
“Current estimates show the 210 million gallons of oil released by the damaged BP Deepwater Horizon Macondo well spread out over the equivalent of 92,500 miles,” the paper adds. “But the oil’s reach was 30% larger than that estimate, the new study says,” partly due to so-called “invisible oil” that was “concentrated below the water’s surface and toxic enough to destroy 50% of the marine life it encountered.”
“Oil in these concentrations for surface water extended beyond the satellite footprint and fishery closures, potentially exterminating a vast amount of planktonic marine organisms across the domain,” the study stated.
Those findings “show that the government’s understanding of how oil flowed from Deepwater Horizon was limited and that it underestimated the extent to which marine life was killed or poisoned by toxic crude,” the Post says. The revelation comes with the Trump administration “preparing to finalize a sweeping proposal that would allow the oil and gas industry to buy leases in every part of the Atlantic, Pacific, and Arctic oceans, in addition to a leasing expansion in the Gulf.”
The Post traces the findings to a model developed by senior study author Claire Paris-Limouzy, an ocean scientist at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science, that “provided a fuller picture of the oil’s footprint” than the two-dimensional satellite imagery other analysts were using. The more sophisticated model “allowed researchers to trace Deepwater Horizon’s oil from its source and show how it was manipulated by wave action, mixed with ocean plumes, and sank and rose to and from the ocean floor.” That action was augmented when Hurricane Alex brought powerful southerly winds through the Gulf between June 28 and July 1, 2010, “enhancing and mixing and bleaching the Deepwater Horizon oil,” the study said.
After that, Rosenstiel researchers spotted the discrepancy between the satellite images and their own models.
“That is what kicked off our study,” said study co-author and Rosenstiel post-doctoral associate Igal Berenshtein. “The extent was larger than the satellite footprint and the fishery closures” where federal marine scientists had designated contaminated zones. “One of them must be wrong, right? There was strong support that the footprint extended beyond the satellite data and the closures.”
Even though it was less concentrated than the oil on the surface, Berenshtein told the Post the additional contamination was extremely toxic. “Basically, when you have oil combined with ultraviolet light it becomes two times more toxic than oil alone. Oil becomes toxic at very low concentrations.”
And that conclusion “kind of changes the way you think about oil spills,” he added. “I didn’t think this way before I did this study. I assumed the satellite image captures the oil spill, and that’s it. People have to change the way they see this so they know there’s this invisible and toxic component of oil that changes marine life.”
Paris-Limouzy said Deepwater Horizon “was no regular oil spill,” since it “happened in the deep ocean. Between the deep sea floor and the surface is a lot of water,” making the toxic product vulnerable to hurricanes, tropical storms, and natural wave action.
“If you want to respond to this kind of spill, you have to know where the entire mass is, the amount of oil that came out of the well, and know that the footprint is not only on the surface, but in three dimensions,” she told the Post.