Saturday, January 14, 2012
Comprehensive Picture of the Fate of Oil from Deepwater Horizon Spill
In June 2010, a WHOI-led team used the autonomous underwater vehicle Sentry in the Gulf of Mexico to define and characterize the deepsea hydrocarbon plume from the Deepwater Horizon spill. Sentry, equipped with a miniaturized mass spectrometer called TETHYS, was able to crisscross plume boundaries 19 times to help determine the trapped plume’s size, shape, and composition. (Credit: Chris Reddy, Woods Hole Oceanographic Institution)
A new study provides a composite picture of the environmental distribution of oil and gas from the 2010 Deepwater Horizon spill in the Gulf of Mexico. It amasses a vast collection of available atmospheric, surface and subsurface chemical data to assemble a "mass balance" of how much oil and gas was released, where it went and the chemical makeup of the compounds that remained in the air, on the surface, and in the deep water.
The study, "Chemical data quantify Deepwater Horizon hydrocarbon flow rate and environmental distribution," is published online in the Proceedings of the National Academy of Sciences.
The lead author, NOAA research chemist Thomas Ryerson, assembled an all-star team of 14 scientists from diverse backgrounds and organizations including academia, private research institutions and federal labs, all of whom played important roles collecting and analyzing data during the spill. Four scientists from the Woods Hole Oceanographic Institution (WHOI) were integral to the paper: environmental engineer Richard Camilli, and marine chemists Elizabeth Kujawinski, Christopher Reddy, and Jeffrey Seewald. The other nine authors hailed from Texas A&M University, the University of California at Santa Barbara and at Irvine, the University of Miami, and the University of Colorado.
"This paper is exciting for several reasons," said Reddy, a WHOI senior scientist who specializes in oil spills. "This is a study based on data from the Gulf and not on models, and it tells the big picture of this spill just 18 months after the leak was capped -- a remarkably short amount of time." Reddy further emphasized the importance of the array of scientists Ryerson assembled to help tell this story. "He brought together key players to analyze relatively new data that came from an impressive array of sampling techniques."
In addition to hydrocarbon data Ryerson collected from overflights on NOAA P-3 planes and other air samples from research vessels, the paper incorporates data collected by a remotely operated vehicle (ROV) using a unique device developed by Seewald to sample the leaking fluid at the well, as well as data from the WHOI-designed and -built autonomous underwater vehicle Sentry outfitted with a miniaturized mass spectrometer developed by Camilli. Additionally, it uses many water samples from various depths taken and analyzed by Reddy, Camilli, Kujawinski, and others, using finely-tuned analytical instruments and techniques to track minute amounts of the oil and gas components.