Donald B. Peters

ASIS—A New Air–Sea Interaction Spar Buoy: Design and Performance at Sea

Abstract This paper describes a new, compact buoy, the Air–Sea Interaction Spar (ASIS), capable of reliably and accurately measuring directional wave spectra, atmospheric surface fluxes, and radiation in the the open ocean. The ASIS buoy is a stable platform and has low flow disturbance characteristics in both atmospheric and oceanic surface boundary layers. The buoy has been deployed for sea trials in the waters off Miami, Florida; in the northeastern region of the Gulf of Mexico; and in the northwestern Mediterranean. The acquired measurements of directional wave spectra, momentum and heat fluxes, and profile data—as well as general meteorological and oceanographic parameters—obtained from the buoy are well suited for enhancing research on air–water interfacial processes, wave dynamics, remote sensing, and gas transfer. In this paper the design is described and the performance of the buoy using field data is characterized.

The Nereus hybrid underwater robotic vehicle for global ocean science operations to 11,000m depth

This paper reports an overview of the new Nereus hybrid underwater vehicle and summarizes the vehicles performance during its first sea trials in November 2007. Nereus is a novel operational underwater vehicle designed to perform scientific survey and sampling to the full depth of the ocean of 11,000 meters - almost twice the depth of any present-day operational vehicle. Nereus operates in two different modes. For broad area survey, the vehicle can operate untethered as an autonomous underwater vehicle (AUV) capable of exploring and mapping the sea floor with sonars and cameras. For close up imaging and sampling, Nereus can be converted at sea to operate as a tethered remotely operated vehicle (ROV). This paper reports the overall vehicle design and design elements including ceramic pressure housings and flotation spheres; manipulator and sampling system; light fiber optic tether; lighting and imaging; power and propulsion; navigation; vehicle dynamics and control; and acoustic communications.

Ice-tethered profilers sample the upper Arctic Ocean

Studies conducted over the past decade indicate that the Arctic may be both a sensitive indicator of climate change and an active agent in climate variability. Although progress has been made in understanding the Arctics coupled atmosphere-ice-ocean system, documentation of its evolution is hindered by a sparse data archive. This observational gap represents a critical shortcoming of the ‘global’ ocean observing systems ability to quantify the complex interrelated atmospheric, oceanic, and terrestrial changes now under way throughout the Arctic and that have demonstrated repercussions for society [Symon et al., 2005]. Motivated by the Argo float program, an international effort to maintain an ensemble of approximately 3000 autonomous profiling instruments throughout the temperate oceans (see http://w3.jcommops.org), a new instrument, the ‘Ice-Tethered Profiler’ (ITP) was conceived to repeatedly sample the properties of the ice-covered Arctic Ocean at high vertical resolution over time periods of up to three years.

Ceramic External Pressure Housings for Deep Sea Vehicles

Only glasses, ceramic and carbon fiber reinforced plastic can provide the necessary weight to strength ratio to make the external pressure housings for undersea vehicles positively buoyant at the abyssal design depth. This group of materials poses unique challenges to the designer and fabricator of pressure housings. This paper summarizes the findings of the R & D program aimed at developing the technology for the design, fabrication, and testing of ceramic housings culminating in the application of ceramic housings to the WHOI ROV/AUV diving system with 36,000 ft (11,000 m) capability

Mooring developments for autonomous ocean-sampling networks

Two general-purpose mooring designs have been developed to support autonomous underwater vehicle (AUV) operations in autonomous ocean sampling networks (AOSNs). These moorings provide two-way communications between investigators and AUVs docked on the moorings or conducting survey operations some distance from the moorings. A deep-water design that incorporates an AUV dock and recharging station was built for use in the Labrador Sea during the winter of 1997/1998. This severe winter environment required a robust design that could operate unattended for six months while isolating the dock from surface wave motion. A much lighter, easier-to-deploy design was developed for use in coastal waters to extend the nearshore AOSN operating area by extending the communications network. This coastal design has been deployed without the dock component and has typically been configured for use in a small network of moorings maintained with a small research vessel. The deep-water mooring has been deployed successfully on two occasions, for short periods of time. The coastal moorings have been deployed a number of times and have proven to be quite effective. This paper describes the two moorings in detail and provides information on their performance so that interested investigators can utilize the technology where it meets their needs.

Design and operation of automated ice-tethered profilers for real-time seawater observations in the polar oceans

Funding was provided by the National Science Foundation under Contract Nos. OCE-0324233 and ARC-0519899.

ULTRAMOOR: a 5-year current meter mooring

The prototype ULTRAMOOR design is a subsurface mooring that supports 10 (or more) discrete acoustic current meters. Travel time and acoustic Doppler sensors are being evaluated. Each current sensor is equipped with a small, low power acoustic transmitter that transfers compressed data from the instrument to a receiver located below the euphotic zone (nominally at 500-m depth). The acoustic receiver forwards these data to an array of up to 10 expendable data capsules. In a typical scenario a capsule would release every 6 months over a 5-year deployment interval. Each capsule contains 4 Mbytes of solid-state memory and an Orbcomm transceiver, which transfers the data via satellite as the capsule drifts away from the mooring. The initial deep ocean test of the ULTRAMOOR prototype will be conducted from July to November 2000 offshore Bermuda. This paper describes the overall system design and discusses its scientific applications.

A Deep Sea Docking Station for ODYSSEY Class Autonomous Underwater Vehicles

Abstract : Under subcontract to the Massachusetts Institute of Technologys (MIT) Sea Grant Autonomous Ocean Sampling Network (AOSN) program, engineers and researchers at the Woods Hole Oceanographic Institution (WHOI) designed, fabricated and operated a deep sea Docking Station for ODYSSEY class autonomous underwater vehicles (AUVs). The docking station provides shelter as well as power transfer and data exchange services for an AUV that is between autonomous midwater missions. The Station is integrated into the main tension member of a deep sea mooring system. A large subsea flotation sphere supports the mass of the Station above the seafloor. A surface expression connected by an umbilical to the Station was capable of bi-directional satellite or radio frequency communications. Primary subsystems of the Docking Station described in this report include a dock controller with multi-sensor support, long duration battery packs, a docking pole with a moving carriage, an inductive link for power and data transfer, and information about how the Station was deployed, operated and recovered.

Deployment operation procedures for the WHOI Ice-Tethered Profiler

Funding was provided by the National Science Foundation under Grant No. OCE-0324233 and by the Office of Polar Programs under award numbers ARC-0519899 and ARC-0631951.

The Bermuda Testbed Mooring and HALE-ALOHA Mooring Programs: Innovative Deep-Sea Global Observatories

Interdisciplinary time series observations are important for understanding and predicting ocean variability on time scales from seconds to decades. Plans are being made to implement open ocean observatories at key sites in the world ocean (e.g., OceanSITES and ORION). The Bermuda Testbed Mooring (BTM), located southeast of Bermuda (BATS site), and the HALE-ALOHA (H-A) mooring, north of Hawaii (HOT site) are prototypes for autonomous sampling interdisciplinary open ocean observatories. Both moorings are located in the deep sea (over 4500 m water depth) and provide fundamental measurements of meteorological, physical, biogeochemical, biological, and optical variables. Many of the present national and international ocean observatory plans have benefited from BTM and H-A research and development. Both programs provide stimuli for many forward-looking ideas concerning ocean technologies and the synergistic use of observations and models. New measurement systems and scientific results from the BTM and H-A projects are leading to improved sampling relevant to global biogeochemical cycling, ecosystem dynamics, and climate change as well as to improved predictive modeling in these areas along with air-sea interaction and hurricanes