- Scientists from NASA or the National Oceanic and Atmospheric Administration collaborate to test remote sensing technology for use in oil spill response.
Every day, thousands of gallons of oil seep through cracks in the seafloor and rise to the surface just off the coast of Santa Barbara, California. But this isn’t a disaster zone: it’s one of the world’s largest naturally occurring oil seeps, and it’s been active for thousands of years.
The area’s dependability makes it an important natural laboratory for scientists, including those working on the Marine Oil Spill Thickness (MOST) project, a collaboration between NASA and the National Oceanic and Atmospheric Administration (NOAA) to develop operational automated oil spill detection, oil extent geospatial mapping analytics, and oil thickness characterization applications.
The MOST team is working to create a method for NOAA, the lead federal agency for detecting and tracking coastal oil spills, to use remote sensing data to determine not only where the oil is, but also where the thickest parts are, which is one of the critical missing pieces for directing response and remediation activities. The team just returned from a fall field campaign in Santa Barbara.
“We’re using a radar instrument called UAVSAR to characterize the thickness of the oil within an oil slick,” Cathleen Jones, a MOST co-investigator at NASA’s Jet Propulsion Laboratory in Southern California, explained.
“Thicker oil lasts longer in the environment and harms marine life more than thin oil.” And if you know where it is, you can direct emergency responders to the troubled areas.”
However, SAR images differ from those obtained from other sensors. The instrument sends radar pulses down to the ocean’s surface, and the signals that bounce back are used to detect roughness at the ocean’s surface caused by waves. When oil is present, it dampens the waves, resulting in smoother water areas.
In SAR imagery, these smooth, oily areas appear darker than the surrounding clean water the thicker the oil, the darker the area. The airborne observations must then be validated, which requires the scientists to return to the same area on a boat and manually measure the thickness of the oil.
“We put the sampler, which is like a tube with open ends on both ends, in the water also let it sit there for a moment,” explained Ben Holt, a JPL co-investigator on MOST.