Researchers at Scripps Institution of Oceanography, UC San Diego are now successfully receiving data from a surface current mapping radar on the BP-operated oil platform Atlantis in the Gulf of Mexico.
The system, installed in August, provides radial maps of ocean currents to distances of 80 kilometers (50 miles) on resolutions of two to 3 kilometers (1.2 to 1.9 miles). A primary objective is to use the radar data to identify and map in near real-time the loop current and eddies in the Gulf; the data are also being used to constrain dynamical and statistical models of ocean circulation.
Scripps owns and operates an extensive array of surface current-mapping, high frequency (HF) radars, which are used to map ocean surface currents. This remote sensing technology is normally shore-based, with installations along cliffs and near shorelines in coastal regions. Each HF radar site has one antenna that transmits a radio signal out across the ocean surface, and another that listens for the reflected radio signal after it has bounced off the ocean's waves. By measuring the change in frequency of the radio signal that returns, the system determines how fast the water is moving toward or away from the antenna. The resulting data are processed for viewing near real-time ocean surface currents using a Google Maps interface.
Deployment of such radars on oil rigs had presented a special challenge to researchers; the substantial amounts of metal in their structure can interfere with transmission of the radars' radio signals. For the installation on Atlantis, Scripps worked with radar manufacturer Codar Ocean Sensors in the testing and evaluation of a compact antenna system expressly built for deployment in confined operating areas like operational oil platforms.
"This installation will allow us to learn how best to deploy and operate an HF radar system on an oil platform for monitoring ocean currents," said Scripps Oceanography researcher Eric Terrill, whose team operates the radar. "The research is enabling expansion of shore-based technologies to offshore waters, which in light of recent events in the Gulf of Mexico, will play a role in stewardship of our oceans."
The Scripps team has worked with other teams nationally in the installation and maintenance of a fully operational system of HF radars that maps currents day and night, including in fog or when conditions don't allow for direct observation. Scripps also designed and implemented a national data system for NOAA to allow for continuous access to near real-time currents via the Internet. The system is part of a national network of HF radars facilitated by NOAA's Integrated Ocean Observing System (IOOS).
"This radar provides a new source of ocean current data in a region of the Gulf of Mexico that has always been data-sparse," NOAA HF Radar Project Manager Jack Harlan said. "It's a great example of a private-academic partnership providing data that NOAA will distribute through its Integrated Ocean Observing System (IOOS) benefiting spill response, U.S. Coast Guard search and rescue operations, harmful algal bloom tracking, coastal water quality monitoring and a host of other critical uses."
BP provides funding for engineering and deployment of the Atlantis radar through an ongoing Scripps-BP research collaboration. In 2004, Scripps and BP entered into a long-term collaboration to work on scientific and technical problems of common interest. The partnership enables Scripps to pioneer new technological development that is difficult to fund through federal agencies. The innovative instrumentation and technologies developed and used in this program are useful for academic research and ocean observing programs, and contribute to the capabilities and efficiencies of BP operations and the country's national capabilities to monitor and protect its coastal waters. The collaboration over the past few years has focused primarily on improving our capability to measure and forecast ocean waves and currents in the Gulf of Mexico. Deployment of a second radar system on BP's platform Holstein is planned in early 2011.