Wind redistribution of snow impacts the Ka- and Ku-band radar signatures of Arctic sea ice

Abstract. Wind-driven redistribution of snow on sea ice alters its topography and microstructure, yet the impact these processes radar signatures is poorly understood. Here, we examine effects over Arctic waveforms backscatter obtained from a surface-based, fully polarimetric Ka- Ku-band at incidence angles between 0∘ (nadir) 50∘. Two wind events in November 2019 during Multidisciplinary drifting Observatory for Study Climate (MOSAiC) expedition are evaluated. During both events, changes coefficients nadir observed, coincident with surface measured by terrestrial laser scanner. At frequencies, caused densification uppermost layers, increasing scattering air–snow interface prevalence as dominant surface. The waveform data also detected presence previous interfaces, buried beneath newly deposited snow. additional interfaces could therefore affect range retrieved satellite altimeters. With angles, relative contribution decreases, snow–sea increases. Relative to pre-wind event conditions, azimuthally averaged increases up 8 dB (Ka-band) 5 (Ku-band). Results show substantial variability within scan area all polarizations, response speed direction. Our results that compaction need be accounted interpret airborne measurements snow-covered ice.