By now many of us know the important role of polar-orbiting satellites in providing advanced warning for severe weather, but how about their role during non-weather disasters? Last month marked the 25th anniversary of the Exxon Valdez spill, when shortly after midnight on March 24, 1989, the tanker Exxon Valdez grounded on Bligh Reef in Prince William Sound, Alaska. Within six hours, the Exxon Valdez spilled nearly 11 million gallons of crude oil over the pristine beaches of Prince William Sound, making the incident the largest oil spill in U.S. history to date, only to be surpassed by the 2010 Deepwater Horizon oil spill. Since that time, there have been many improvements in oil spill response and tracking as well as advances in the ability to detect and monitor spills from satellites.
The Visible Infrared Imaging Radiometer Imaging Suite (VIIRS) instrument, currently flying onboard the NOAA-NASA Suomi-NPP satellite and also scheduled to launch aboard NOAA's upcoming JPSS-1 satellite in early 2017 is one such instrument. VIIRS imagery is capable of detecting and monitoring the distribution of oil on the ocean surface during a spill. It offers a new range of possibilities to visualize Earth and its oceans, while concurrently improving the quality of weather forecasts that save lives and protect local economies. VIIRS sea surface temperature measurements, combined with data from other satellites and buoys, will provide critical input to ocean atmosphere coupled models. VIIRS extends and improves upon a series of measurements from the NOAA Advanced Very High Resolution Radiometer (AVHRR) currently flying on NOAA POES satellites and the NASA Moderate Resolution Imaging Spectroradiometer (MODIS) that flies aboard NASA’s Aqua and Terra satellites.
"Our satellites support the four NOAA mission areas, which includes healthy oceans and coastlines," said JPSS Chief Program Scientist Mitch Goldberg, PhD. "If another catastrophic event should occur in the future, NOAA will be able to leverage the capabilities of the instruments to monitor the trajectory of an oil spill, thereby aiding in recovery efforts and protecting wildlife."
NOAA's satellites are now among the many vehicles used to provide scientific support during the assessment, response and cleanup phases of an oil spill. To effectively respond to a spill, emergency managers must know the extent and likely path of the oil spill. For large spills, such as Deepwater Horizon, traditional ship and air-based tracking are quickly overwhelmed and satellites imagery is critical to tracking the extent and path of the oil spill. Satellite analyses can help guide response operations and assist with trajectory modeling. Just two days after the Deepwater Horizon rig exploded on April 20, 2010 NOAA issued the first Satellite-Derived Surface Oil Analysis. During the first hours after the explosion, the U.S. Coast Guard requested help predicting the movement of the spreading oil, and NOAA was there. Two hours and 14 minutes later, NOAA issued the first of many spill trajectory forecasts. Daily forecasts for 24, 48, and 72 where provided by NOAA's Office of Response and Restoration modelers for over 100 days.
"Our trajectory modeling efforts rely on inputs from the field- traditionally that has meant personnel in aircraft looking out the window and tracking the slick," said Doug Helton of NOAA's National Ocean Service Office of Response and Restoration Emergency Response. "Satellite technology gives us another way to track spills, and also help us develop better ocean circulation models, allowing us to prepare more accurate and timely forecasts of oil movement."
Responders and emergency workers rely on NOAA science generated in real time to make the best decisions to protect human life and property. Satellite, surface and subsurface platforms allow NOAA scientists to make direct observations of weather and ocean conditions to support disaster response with accurate and timely information.
The 25th anniversary of the Exxon Valdez spill is a reminder of the damage a spill can cause to oceans and coastal communities. Future VIIRS and JPSS capabilities will be important tools for NOAA to improve the modeling and oil spill trajectory assessments during a catastrophic event.
Click here to view an animation developed by the NOAA Visualization Lab of trajectory of the Deepwater Horizon spill.