Arctic Low-Res (99kbytes)	Antarctic Low-Res (100kbytes)
Arctic Hi-Res (350kbytes)	Antarctic Hi-Res (348kbytes)

These images of polar regions (Arctic = North Pole, Antarctic = South Pole) and the surrounding sea-ice pack were constructed from six days of data taken by the NASA Scatterometer (NSCAT) which was onboard Japan's Advanced Earth Observing Satellite in September 1996. The scatterometer's primary function was to study winds over the oceans, but scientists have devised a way of studying changes in the instrument's radar backscatter to look at land and ice surfaces as well. The black circle in the center of the image is an area where no data were collected due to the orbit of the satellite. The dark band around the continent is the evolving sea-ice pack. The white, rectangular object in the ice pack on the lower left of the image is a 100-kilometer by 50-kilometer "super iceberg" that broke off the Thwaites ice tongue and is now circulating in the sea-ice pack. Other large icebergs are also visible in the image. Antarctica is covered with a thick ice sheet which appears very bright in the image because of the way the snow crust and refrozen ice reflect the scatterometer's radar signal. Details visible in the glacial ice cover show the locations of ice "hills" and "valleys" that give scientists new information about how the ice is flowing under the surface. Scientists are using images like this to understand the effects of the ice pack on the ocean and climate systems. The polar regions play a central role in regulating global climate, and it is important to accurately record and monitor the extent and surface conditions of the Earth's major ice masses. Such monitoring can only be done using spaceborne sensors, and the scatterometer radar remote sensors were uniquely suited for mapping the polar regions since the radar could image the surface through clouds, regardless of sunlight conditions. This instrument provided frequent, all weather, all year monitoring of these vital regions of the Earth. NSCAT was launched from Japan on August 16, 1996. The mission represented the first major collaboration between the two nations in Earth remote-sensing. JPL developed, built and manages the NSCAT instrument for NASA's Mission to Planet Earth program.