Mapping Ice Slabs over Antarctic Ice Shelves using Quad-Polarization L-band Radar Backscatter

<jats:p>Nearly 3 months of enhanced-resolution, quad-polarization, L-band (1.26 GHz) radar backscatter (σo) image time series are used to map the ice slab extent over the percolation facies of Antarctic ice shelves for the first time from space. Distinctive spatial trends in σo, incidence angle, and polarization signatures mapped via principal component analysis (PCA) are used to develop a proof-of-concept polarimetric algorithm that is empirically calibrated using airborne ice-penetrating radar surveys. A previously unidentified ice slab extent of ∼52,000 km2 is mapped over 23 ice shelves in the Antarctic Peninsula as well as West and East Antarctica in locations that experience ≥35 days of surface melting during the austral melting season.</jats:p>