Ice sheet attenuation from radar sounding in the frequency domain

Attenuation rates inferred from radar sounding offer one of the few ways to observationally constrain the large-scale temperature structure of ice sheets. However, existing methods struggle in regions with near-uniform ice thickness or disrupted radiostratigraphy—common across much of Antarctica and Greenland—where direct temperature estimates are most needed. We adapt the spectral ratio method, originally developed for seismic data, to estimate englacial radar attenuation rates, focusing on regions where traditional methods fail. By analyzing the relative amplitude change of surface and bed reflections across the radar bandwidth, we produce fullcolumn attenuation estimates independent of internal layer continuity or significant variability in bed topography. We apply this method to radar surveys in interior Antarctica and Greenland. Our results agree with attenuation rates derived from borehole temperature profiles and alternative radar-based methods, where comparisons are possible. The spectral ratio method is broadly applicable to any radar dataset that preserves the original amplitude spectra. By expanding the spatial coverage of reliable attenuation estimates, our approach enables continental scale mapping of ice sheet temperature.