GDC Project: GISMOGlobal Ice Sheet Mapping Orbiter : A NASA Instrument Incubator Project.

GISMO was a spaceborne radar system designed to measure the surface and basal topography of terrestrial ice sheets and to determine the physical properties of the glacier bed. The primary objective was to develop the technology to obtain spaceborne estimates of the mass of polar ice sheets with an ultimate goal of providing essential information to modelers estimating the mass balance of the ice sheets and their response to changing climate. Our technology concept employed VHF and P-band interferometric radars using a novel clutter rejection technique for measuring the surface and bottom topographies of polar ice sheets. Our approach enabled us to reduce signal contamination from surface clutter, measure the topography of the glacier bed, and paint a picture of variations in bed characteristics. The technology also had applications for planetary exploration including studies of the Martian ice caps and the icy moons of the outer solar system. We showed that it was possible to image a small portion of the base of the polar ice sheets using SAR. Through the concept developed here, we imaged the base and mapped the 3-dimenional basal topography beneath an ice sheet at up to 5 km depth.

GISMO was a NASA Instrument Incubator Project.