Abstract:
Based upon the 1987-88 Arctic Environmental Drifting Buoy (AEDB), the Ice-Ocean Environmental Buoy (IOEB) was developed to
acquire and telemeter in near real-time inter-relatable time-series data on atmospheric, oceanographic and ice physics in ice-covered oceans
during all seasons. Two IOEBs were successfully deployed in two Arctic Sea Basin Stations in April, 1992. Since then, although some
sensors malfunctioned, for 18 continuous months, they have been sending massive amounts of information. In this report we describe the
technology which was developed for the 1991 IOEB. Mechanically, the IOEB consists of an extremely durable surface flotation package
and an underwater mooring line of instruments and sensors. The apex contains data loggers for air, ice and engineering measurements,
microcontroller modules for accumulating the data from all the instruments, and ARGOS platform transmit terminals (PTTs) for
broadcasting the data. Extending above the surface float, a mast supports a wind monitor and air temperature probe, which along with a
barometer provides meteorological data. Thermistor strings, vibrating wire stress sensors, and a thickness gauge are installed in the ice
surrounding the buoy, and are interrogated by the modules inside the apex. In the ocean, 110m of conducting strength cable passes the
data from conductivity/temperature recorders, an Acoustic Doppler Current Profier and data compression module, a dissolved oxygen
sensor, a transmissometer and fluorometers to the PTT microcontrollers. Furthermore, a suspended particle collector and sediment trap
transmit status information along the two-wire multidrop network cable. Because the IOEB differs from the AEDB by telemetering the
majority of the scientific data, a complicated compression scheme is incorporated to broadcast the data from the 103 variables within the
allowable 256-bit ARGOS data stream. Via Service ARGOS, this data currently becomes available to scientists in several countries within
eight hours of transmission.
In April 1992, two IOEBs were deployed at separate ice camps in the Arctic Ocean with battery power adequate to sustain the systems for
over two years. One was deployed 115 miles from the North Pole in the center of the Transpolar Drift sea-ice current, and the other off of
the coast of Alaska along the edge of the Beaufort Gyre. Airplanes capable of landing on ice were used for the transportation of the systems
to their final destination. Simultaneously, a third, reduced version of the IOEB was deployed in the Weddell Sea by the Scott Polar
Research Institute.
