Detailed elevation map of Ice Stream C, Antarctica, using satellite imagery and airborne radar

Abstract

Surface elevations collected by airborne radar arc interpolated between flight lines using Landsat I'M image data to produce a detailed digital elevation model of a part of Ice Stream C, West Antarctica. The photodinometric method developed is general and allows the derivation of surface elevation along any line parallel to the solar illumination from a single known elevation on that line. Accuracies of the derived elevations are improved with additional elevation control that permits an empirical determination of parameters in the photoclinometric equation accounting for albedo and atmospheric scattering. Elevation errors increase approximately linearly with the integration distance. An explicit relationship is derived that shows the image brightness is insensitive to the cross-Sun component of small surface slopes typical of ice sheets. The greatest impediment to the accuracy of this technique is the radiance resolution of the sensor which limits the signal-to-noise ratio of the image data and can mask variations in albedo that are falsely converted to variations in surface slope.