In a recent study of the 2010 Deepwater Horizon Oil Spill, researchers discovered that approximately 10 percent of oil spilled in the Gulf of Mexico was dissolved by sunlight.
Oil can partially dissipate and dissolve in seawater through natural processes, which scientists account for. These include microorganisms degrading the oil, evaporation, or the oil drifting onto shores. Recently, though, a team of researchers from the Woods Hole Oceanographic Institution (WHOI) found that sunlight plays a significant role in the removal of oil through a process called photo-dissolution.
How does sunlight remove oil?
Through photo-dissolution, oxygenation reactions caused by sunlight can take insoluble parts of oil on seawater and transform them into water-soluble products.
This process was examined by putting samples ofAll Posts oil from Deepwater Horizon on glass sample disks and exposing them to radiation from LEDs with the same wavelength as sunlight. They found that between 3 to 17 percent of the Deepwater Horizon spilled oil may have been dissolved into organic carbon. Estimates put the actual number somewhere between eight to 10 percent, to be on the safe side.
How will this help in the future?
Precision is key in environmental disaster cleanup. Knowing the specifics of photo-dissolution on oil helps to better understand the spill record of disasters like Deepwater Horizon, knowing how much of the oil is where and what to do with it.
“One of the most fascinating aspects of this finding is that it might impact our understanding of where else the oil is going, and whether the result is good or bad,” Danielle Haas Freeman, a Massachusetts Institute of Technology/WHOI Joint Program student, said in a press release.
As reported in The Hill, the team was able to create scenarios and simulations of potential oil spills using input from what they now know about photo-dissolution, better preparing for potential future spills.