ALOHA Cabled Observatory: Installation and Operation

University Of Hawaii, Honolulu

Investigators

Abstract

The PI requests funding to complete the installation of the ALOHA Cabled Observatory (ACO) and begin operations. This is a continuation of the ACO project which was proposed to provide infrastructure in support of real-time science at Station ALOHA, the site of more than 20 years of deep water oceanographic investigations 100 km north of Oahu, Hawaii. The ACO uses a retired commercial telecommunications cable donated by AT&T to provide an ?extension cord? from shore to Station ALOHA. The observatory node contains eight ports that investigators can plug into on the ocean floor, using an ROV, to obtain continuous electrical power and an Internet connection between their instruments, their desk on shore, and anywhere else on the Internet. The first phase of installation was completed in February 2007, which included cutting, moving, and terminating the end of the cable at Station ALOHA. An experiment package was connected directly to the cable and has proved the design concepts by transmitting 20 months of nearly continuous pressure and acoustic data to shore in real time. An attempt to install the Phase-2 node of the ACO in October 2008 was thwarted by the failure of commercial underwater optical connectors within the observatory. Basic science instrumentation installed will uniquely address abyssal science questions will also be installed, including acoustic Doppler current profilers, conductivity, temperature and depth sensors, an acoustic modem, a 200-m-tall bottom-moored thermistor array, hydrophones, an absolute pressure sensor, bio-optical sensors, and a video camera. Broader Impacts: This proposal will have a broader impact on other ocean observatories by monitoring the maturity of WMC design and manufacturing in a cooperative program with the supplier. It is anticipated that this work will improve the WMC enabling technology that can then be used more confidently by other observatories. The past work has highlighted one of the most important lessons of ocean engineering -- TEST, TEST, TEST. By continuing this activity, the ocean community will have another test bed (with MARS) to use in improving the emerging enabling technologies. The proposed activity pushes the technological observational envelope for deep ocean science. Together with gliders and other AUVs, cabled observatories will move ocean science beyond the limitations of research vessels and conventional moored buoys. The development of ALOHA will be a community resource. It will leverage off existing outreach efforts associated with HOT and C-MORE. It offers new ways of engaging larger numbers of the student community and the general public in ongoing deep water research at on-costs vastly below those of running a research ship to achieve the same scientific objectives.