L-Band Radar Sounder for Measuing Ice Basal Conditions and Ice-Shelf Melt Rate

A new L-band radar system is proposed to measure ice thickness, basal conditions and ice-shelves bottom melt rates. The concept for ice measurements with an L-band radar is based on the recent success in sounding shallow low-loss ice (<; 1 km) and measuring ice-self melt rates with a 600-900 MHz low-power radar, referred to as accumulation radar [1]. A surface-based radar operating over 1.2-1.4 GHz with a peak transmit power of 2 kW is proposed to sound and image more than 4 km thick ice. The higher frequency at 1.3 GHz will provide the sensitivity required to detect basal water film as thin as 0.5 mm as compared to radars operating now at frequencies less than 600 MHz. These radars need a minimum film thickness of 4 mm or more for reliable detection. The proposed L-band radar will also measure the bottom melt rate of ice shelves. The current plan is to deploy the proposed radar for field test in Antarctica during the 2018-2019 field season.