This image of sea-ice drift in the Artic basin was derived from NSCAT observations made on December 24, 1996. The white arrows indicate velocities based on tracking that used wavelet analysis; red arrows indicate velocities calculated from data obtained by buoys in the Artic Ocean. Agreement between the data sources establishes NSCAT as a suitable sensor for ice motion. A series of daily ice-drift maps derived from NSCAT shows that current reversal is a resulte of changes in winds. [From Liu, A. K., Y. Zhao, and W. T. Liu, 1998: Sea ice motion derived from satellite agrees with buoy observations. Eos Trans. Amer. Geophys. Union, 79, 353 & 359].