The ICYCLER is a moored oceanographic profiler designed to measure surface layer water properties under mobile ice cover. The instrumentation is deployed in the Canadian Arctic Archipelago to measure the surface properties passing from the Arctic Ocean to the Atlantic Ocean. The profiler is designed to provide daily 50-meter salinity-temperature-chlorophyll profiles for a full year. An ICYCLER prototype was successfully used in the Canadian Arctic Archipelago during a year-long deployment. A second re-designed ICYCLER was deployed in the summer of 2007 and provided a second yearlong record.
The ICYCLER consists of a two-float assembly. The main (lower) float serves as a mid-water platform below the ice hazard zone from which profiling is initiated (Fig. 1). Below this depth, traditional moorings can be used. The main float reduces energy consumption by enabling a much smaller float to lift the sensors the rest of the way towards the surface.
The ICYCLER’s sensor float uses a streamlined OpenSeas "SUB" enclosure to house a Seabird 19+ CTD with pump and a Wetlabs fluorometer to collect data, while a Datasonics echo sounder monitors the distance to the underside of the ice during each profile. Sensor data are relayed to electronics located on the mid-water platform via electro-mechanical cable. The electronics provide data storage, and control the height to which sensors profile.
The upper float is outfitted with the profiler and its line is an electro-mechanical cable that carries power and data signals. The lower float has a kevlar mooring line and is bottom-fixed. Each of the lines is wrapped on a separate drum. The drum for the electro-mechanical cable is motorized and also carries the power supply. The drums are interconnected and work in opposite directions: while the upper drum is paying out the lower drum is hauling in. As the topmost float travels upwards, the lower float goes down its mooring line.
Energy requirements are low since the upper float uses its buoyancy to rise reducing its potential energy and the lower float gains potential energy. The maximum height that the upper float reaches is controlled by sonar and once it is attained the process reverses and the floats return to their original positions.
If the distance travelled by the topmost float is much greater than the distance travelled by the lower float and the buoyancy of the upper float is much less than that of the lower float, then conservation of energy requires that the distances travelled by the buoys be determined by the ratio of their buoyancies. With only friction/drag to overcome, the energy requirements are minimal and profiling can endure for a long time.
Fowler, G. A. 2002. "A moored energy-conserving oceanographic profiler
Fowler, G. A., G. R. Siddall, and S. J. Prinsenberg. 2004. "An energy-conserving oceanographic profiler for use under mobile ice cover: ICYCLER"
Prinsenberg, S. J., R. Pettipas, G. A. Fowler, and G. R. Siddall. 2007. "The ups and downs in developing an under-ice moored profiler called the ICYCLER"
Prinsenberg, S. J., J. Hamilton, I. Peterson, and R. Pettipas. 2008. "Observing and interpreting the seasonal variablity of the oceanographic fluxes passing through Lancaster Sound of the Canadian Arctic Archipelago"
