Ultra-Wideband Radar for Measurements over Ice Sheets in Antarc-tica and Greenland

Significant progress has been made in the development of next-generation ice-sheet models to simulate the response of large ice sheets in a warming climate and to determine their contribution to sea level rise over the next century. Good progress has also been made in characterizing the bed topography of a few key outlet glaciers in Greenland and Antarctica. These new models and data have been used to generate sea level rise projections of between 26 and 98 cm by the end of this century. However, there is still a need to better understand both ice-stream dynamics near the grounding lines and ice-shelf-ocean interactions, as well as to incorporate this understanding into improved models to reduce the large uncertainly in sea level rise predictions. We developed an ultra-wideband radar that operates over a frequency range of 150-450 MHz for fine-resolution measurements over the ice sheets in Antarctica and Greenland. This radar was developed specifically to obtain measurements over ice shelves and fast-flowing glaciers. The current antenna-array, which consists of eight elements, is housed in a certified antenna structure for a Basler aircraft. It will be soon expanded to 24 elements to cover a wider frequency range (150-600 MHz). During December 2013 and January 2014, we collected data over a few ice streams and glaciers in Antarctica. This paper will provide an overview of the radar, antenna array and results from the 2013-2014 deployment in Antarctica, as well as our plans for a larger array and wider bandwidth system.