A significant fraction of the vast amounts of the 500,000 tons of natural gas injected into the water column during the 2010 BP oil spill was not consumed by bacteria by the end of that August, as had been thought.
This news came out today, May 11, in a peer-reviewed scientific paper published in Nature Geoscience online.
Dr. Samantha ("Mandy") Joye, a Univ. of Georgia biogeochemist who's been studying the Gulf for many years, along with several other scientists, concludes that methane-oxidizing bacteria (called methanotrophs) declined rapidly before the well's discharge was finally shut, suggesting that factors other than methane regulate an ecosystem after a spill.
Oil began spewing Apr. 20, 2010 following the explosion of the Deepwater Horizon rig, which led to 11 workers losing their lives. The well was finally capped under the leadership of Admiral Thad Allen with the US Coast Guard. He had come out of retirement to perform this duty, before stepping down following the shut-off July 15, after 84 days of horrific spewing.
The pollution wreaked yet-untold and immeasurable havoc in the Gulf, not only for the environment itself but for marine life, wildlife and humans.
In "The rise and fall of methanotrophy following a deepwater oil-well blowout", Joye along with 17 co-authors including M. Crespo-Medina, C. D. Meile and K. S. Hunter show how they measured methane concentrations in the water column along with the activity of methane-oxidizing bacteria in the nine months following the blowout.
They found that rates of methane consumption rose rapidly in May and early June, but dramatically declined in late June — although methane was still being released from the well. Thus, elevated methane levels lingered until at least the end of the year.
Even at 250 days post-spill, methane concentration was very high, as evidenced by a diagram accompanying the paper.
The authors state, too, that:
We show that although gas-rich deepwater plumes were a short-lived feature, water column concentrations of methane remained above background levels throughout the rest of the year...
Methane, a component of natural gas and also found in deep-sea geologic formations, is a highly combustible greenhouse gas. Atmospheric methane spurs on climate change.
Joye recently returned from a trip back out to the wellhead site in the Alvin submersible vehicle in order to obtain samples related to evidence of methane. Back in the fall of 2011, she was one of the most prominent voices questioning the "all clear" message many were voicing after Corexit dispersed the oil. Dr. Joye was adamant at the time that what was on the sea floor painted a far different picture -- in this case, a pink one.
I reported then that,
In a November dive she found mysteriously red and pink sediments in the middle of the Orca basin, as colorfully discussed and shown in her Gulf oil spill blog.
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Bold marks and hyperlinks are the examiner's.