A High-Resolution Airborne Radar System for Near Surface Mapping of Internal Layers to Estimate Accumulation Rate

We developed a 600-90-MHz airborne radar system for high-resolution mapping of the near surface internal layers for estimating accumulation rate of polar ice sheets. Accumulation rate is currently determined by analyzing ice cores and snow pits. Inadequate sampling of the spatial variations in the accumulation of the ice sheet has resulted in accumulation rate uncertainties as large as 24%. Our airborne radar system can provide improved spatial and temporal coverage by mapping a continuous profile of the isochronous layers in the ice sheet. We successfully mapped the internal layers of the Greenland ice sheet with better than 1 m resolution up to a depth of 200 meters. We also developed a radar target simulator to help characterize the system indoors, since we are unable to test the system in the continental USA due to interference from and to wireless communication devices that operate in the UHF band.