Instrument Development

Autonomous Surface Vehicles (ASVs) developed primarily at GSO carry a variety of sensors to detail current, temperature, dissolved oxygen salinity, and can characterize sediments with side-scan sonar. A small and light remote-controlled ASV (kayak-size) operates for up to eight hours at a time and serves research and educational purposes in the Bay. A larger 30-ft catamaran ASV conducts research in the Bay and offshore coastal waters. Also remotely controlled, the catamaran is designed to operate for weeks at a time. Results from these studies enhance our understanding of physical and biological processes in our nearby marine environment.

Scientists deploy a Model 6.2 Inverted Echo Sounder, produced by GSO/URI. Photo credit: Dynamics of Ocean Currents and Fronts Lab.
Scientists deploy a Model 6.2 Inverted Echo Sounder, produced by GSO/URI. Photo credit: Dynamics of Ocean Currents and Fronts Lab.

Whereas ADCPs look downward in the ocean for movement of currents, GSO-designed inverted echo sounders with an additional pressure sensor (PIES) are moored on the ocean bottom and look upwards to ascertain currents and density above. These PIES, deployed by GSO physical oceanographers in the Kuroshio Current, the Antarctic circumpolar current, the Loop Current in the Gulf of Mexico, and the Gulf Stream, among others, have increased our knowledge of the speed, direction, sources and fates of the major currents in the oceans.

The Wire Flyer, developed by GSO scientists, is an instrument deployed along a vertical wire towed from a moving ship and designed to move up and down the wire on command. Capable of being fitted with a variety of sensors, its primary use is to measure horizontal seawater CTD (conductivity or salinity, temperature, and depth) variations rather than just the vertical variations experienced from a standard CTD cast.

The HOLOCAM, a holographic camera system, is deployed in in East Sound, Washington, for a field test.
The HOLOCAM, a holographic camera system, is deployed in in East Sound, Washington, for a field test. Credit Jim Sullivan .

Viewing and recording particles in the ocean help to understand mechanisms responsible for plankton interactions and spatio-temporal dynamics. The development of an in-situ holographic camera (HOLOCAM) with high and low magnification systems leads to the imaging of phytoplankton and other particles within an unusually wide range of sizes (~1 to 1000s µm), and directly in natural systems.

In the field, GSO oceanographers enhance the technological capabilities of a submersible underwater flow cytometer to distinguish between phytoplankton species by using size and unique optical signatures. These inherent cellular properties provide tools for quantifying the development and fate of blooms of certain species, and for separating live from dead cells.

On a more applied research front, GSO scientists designed and built a calibrated water-jet apparatus to test adhesion strength of fouling organisms to allow for comparing experimental coatings or surfaces developed to solve issues related to biofouling on man-made structures (e.g., ship hulls, underwater sensors).