July 19, 2006
MBARI creates revolutionary deep-sea observatory 100 kilometers offshore of the Central California coast
Last week, after almost five years of development, MBARI engineers and scientists celebrated the deployment of a new oceanographic mooring that connects instruments on the deep seafloor with solar panels and a data relay system at the sea surface. The resulting deep-sea observatory is one of only a few such installations world-wide.
The newly-installed surface buoy and seafloor instruments were deployed at the Shepard Meander, 100 kilometers offshore of the Central California coast, in water almost 3,200 meters (two miles) deep. Data from this observatory may help scientists solve a longstanding oceanographic mystery—how animals on the deep seafloor get enough to eat.
Here’s how the Shepard Meander observatory system works: The surface buoy supports solar panels and a wind turbine that generate electricity. This electricity is sent down through a four-kilometer-long cable to the seafloor. Extension cables laid along the seafloor carry the electricity to scientific instruments up to several kilometers away.
The observatory’s instruments on the seafloor collect information on oceanographic conditions such as water temperature, water clarity, and currents. This information is sent back to the surface through fiber-optic strands in the seafloor extension cables and the main mooring cable. Once the data reaches the surface buoy, it is relayed to shore via satellite. This live data is then automatically displayed on the MBARI web site by MBARI’s Shore-Side Data System (SSDS).
MBARI engineers have been working on various parts of this project since 1998, as part as the Monterey Ocean Observatory System (MOOS). One significant engineering challenge was developing an anchor cable that could not only hold the surface buoy in place, but also transmit electricity and data between the surface and the seafloor. In addition to extensive computer modeling, this cable-design process also involved some trial and error field testing. Despite setbacks, the engineering team persevered and eventually developed a new cable design. After testing their new cable for the the past year, the engineers feel confident that it will be able to survive all but the most extreme winter storms.
The new observatory was installed in several stages. First the surface buoy, surface-to-seafloor cable, and anchor were deployed. After initial tests showed that the data and power connections to the seafloor were working properly, ROV Tiburon was sent down to lay the extension cable from the anchor to a cluster of scientific instruments about three kilometers away. This step (laying the cable on the seafloor using the ROV) was another major engineering feat, which required several years of research and development by MBARI engineers working closely with MBARI’s ROV pilots.
In the final step of the deployment, ROV Tiburon carried a cluster of scientific instruments (known as a “benthic instrument node” or BIN) down to the seafloor and hooked the instruments up to the previously laid extension cable. The system was then switched on using a radio link from the Western Flyer, and the team celebrated as new observatory returned its first data.
The creation of this new observatory was a long and challenging process that involved dozens of MBARI staff, and required close coordination between engineers, scientists, ROV pilots, and the crew of the R/V Western Flyer. As data from the observatory pour in, ocean scientists at MBARI and elsewhere will be taking advantage of this unique opportunity to monitor changes in the deep sea in real time.
For additional information or images relating to this article, please contact: Kim Fulton-Bennett