An integrated system for measuring sea ice motions

One of the objectives of the AIDJEX Spring 1972 Pilot Study was to develop an improved ability to measure the motions of sea ice in the central Arctic Ocean. An integrated system is described in which the basic measurements of position are acquired by the Navy Navigation Satellite System and a specially designed hydroacoustic tracking system. Celestial observations of ice floe azimuth give the system additional redundancy. These measurements are then related to ice velocities and accelerations by a series of time difference equations. Kalman filtering techniques are used in the data processing scheme. The power of this system was indicated by simulation runs and later confirmed by analysis of the field data. It appears that such a system can resolve the full spectrum of ice motions.