Sea-ice motion derived from satellite agrees with buoy observations



Satellite measurements are providing daily views of sea-ice motion in the polar regions. This unprecedented capability will lead to routine monitoring of ice flow for climate change studies and ship-routing applications. In 1996, the NASA Scatterometer (NSCAT) rode into orbit on the Japanese satellite ADEOS and gathered 8.5 months of valuable wind data. Designed to observe wind speeds and directions over the ocean surface, NSCAT data also achieved exciting and totally unanticipated success in measuring sea-ice motion—an application for which it was never intended. The wavelettransform method is used to track ice features in the NSCAT imagery and the results are validated against Arctic drifting buoy data. The wavelet-transform procedure is robust, and NSCAT's unprecedented ability to determine daily sea-ice motion independent of clouds and at a 25-km resolution will have profound impacts on global climate change research.