Ku- and Ka-band Radar Penetration and Scattering - Altimetric Measurements over Evolving Snow and Sea Ice during MOSAiC

Abstract:

Satellite radar altimetry provides pan-Arctic estimates of sea ice thickness; a key uncertainty in retrieved thickness estimates is the effect of an overlying snow cover on the radar signal, relating to the penetration and scattering of Ku-band radar in the snow cover. The potential to retrieve snow depth on sea ice through differencing laser and Ka-band, with Ku-band elevations has been demonstrated, assuming the echo peaks originate at the snow/ice (Ku-band) and air/snow (laser and Ka-band) interfaces. However, it has also previously been shown through field observations and modelling that the main scattering horizon of a Ku-band radar is not necessarily the snow/ice interface. Field data to investigate the echo characteristics are limited in space and time due to the difficulty of collecting measurements in the field. MOSAiC provides a unique opportunity to obtain a dataset using a Ku- and Ka-band radar deployed over sea ice and gathering data as the snow pack evolves through the seasons, utilising the polarimetric capabilities of the KuKa radar instrument. We present results which demonstrate the effects of the snow characteristics on the Ku- and Ka-band echoes and the potential to retrieve snow depth using these radar data.