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as the probe is kept suspended above the surface inside the buoy when not profling, the equipment is practically maintenance-free in between routine annual service. An additional bonus is the possibility to calibrate the oxygen probe automatically from the atmospheric oxygen concentration. The probe, weighing approximately 6 to 8 kilograms in air depending on the amount of auxiliary equipment, hangs from a 4-millimeter nylon rope with up to 150 meters range on the winch. The lightness of the dynamic parts (probe and rope) makes the winching itself��� which is the most energy-demanding operation���relatively low-consuming, so it can be sustained by mounted solar panels or miniature wind turbines on the buoy. The data as well as remote control commands are transmitted from the buoy to the user via the Internet. The embedded server is accessible via the HTTP protocol, FTP, SMS or Wi-Fi. If network coverage is unavailable, satellite communication can be provided. The modern network-based communication makes the buoy and data transfer accessible in real time through standard PC, tablet and mobile-phone equipment. One to several users can access the buoy independently from any location over the Internet. All commands, such as start, stop, frequency, range and depth intervals of profling, as well as diagnostic routines, are performed through online menus, and the return and downloading of incoming data is equally simple. The server in the buoy will store and keep incoming data in between downloading and can store data for up to two years. Malfunctioning will be instantly reported, in which case, the buoy will automatically go into hibernation. Results From Field Tests The buoy was tested by prototypes in two separate coastal locations in Norway for more than two years of continued bihourly profle operations in all kinds of weather. One site was a commercial salmon farm near Bergen, Norway, where the equipment was mounted inside a foating holding pen rearing Atlantic salmon, and the other site was a permanent hydrographic monitoring station in the H��gsfjorden fjord near Stavanger, Norway, which has been operating continuously since June 2010. The data from the salmon cage, which began being gathered in September 2011, are processed by a dedicated software application called the Welfaremeter, developed by the Institute of Marine Research in Bergen, Norway. This application, which continuously stores and analyzes the incoming data using a database, gives a real-time evaluation of the environmental conditions in the cage as either very good, good or potentially harmful for the fsh. The results are graphically displayed and updated on a Web page so that a farmer has instant control of his fsh cages via PC, tablet or mobile phone. The data from the H��gsfjorden buoy, being collected by EWOS Innovation, a Norwegian commercial aquaculture feed company, is used primarily to monitor the surface layers of low-salinity water stemming from freshwater runoff. The data are being used to investigate the dynamics between salmon sea-lice infestation and salinity gradients of the water column. Future Potential This APB5 buoy is the frst generation in an envisioned series of internationally cooperating measuring platforms based on the present product. SAIV AS has received inquiries for possible positioning of the equipment on foating ice in the Arctic as part of ongoing climate research programs. The buoy can be extended to support acoustic Doppler current meters and atmospheric weather stations. The company also foresees a huge and growing interest from the aquaculture industry, where intensive offshore rearing in larger sea cages combined with increased user demands for healthy conditions for both the fsh and the ambient environment will require high-resolution monitoring of reliable real-time data. Furthermore, the buoy can be used for any activities requiring continued water quality monitoring, such as flling, mining or drilling. n Monica S. Kolding is a marine biologist and manager at SAIV AS in Bergen, Norway. She has a master���s degree in marine biology from the University of Bergen, with a focus on pollution effects from aquaculture sea cages. B��rd Sagstad works as an electronic engineer and product developer at SAIV AS in Bergen, Norway. He has a bachelor���s degree in electronics from Bergen University College and a master���s in information technology from Griffth University in Australia. 12 st / FEBRUARY 2013 www.sea-technology.com