Multichannel Coherent Radar Depth Sounder/Imager Data Products Over the Greenland Ice Sheet as Part of NASA's 2012 Arctic IceBridge Campaign

NASA's Operation IceBridge is an airborne mission with a suite of instrumentation used to collect data in the earth's polar regions. The program is aimed at bridging the data gap in NASA's ICESat satellite missions. The Center for Remote Sensing of Ice Sheets (CReSIS) has been operating radars as a part of these missions and collected a large volume of data over the Arctic and Antarctic ice sheets and sea ice. The radars are collectively capable of providing complete surface-to-bedrock profiles of glacial ice and measuring thickness of snow cover over sea ice with very fine resolution. One of the radars is a Multichannel Coherent Depth Sounder/Imager (MCoRDS/I) used to measure ice thickness for generating bed topography and grounding-line position. During the 2012 Arctic campaign, the MCoRDS/I system was operated from NASA's P-3 aircraft on 32 flights and recorded 54 TB of data. Results from the campaign demonstrate the radar's sensitivity to echoes from deep internal layers near the bedrock in the middle of the ice sheet. Figure 1 shows a radar echogram from data collected over a continuous 104.6 km flight line near the NGRIP drill site. The figure (zoomed in on echoes returning from 2.3 to 3.3 km below the surface) shows layers up to 2.9 km below the air/ice interface in 3.2 km thick ice. Below this depth, 2.9 km, a broad return can be seen that is probably due to either disturbances in the ice caused by ice flow or ice crystal characteristics. With further improvements planned for our radars, we can probably map layers below 2.9 km in the future. This paper will present results similar to those in Figure 1 for different areas of the ice sheet in the Northern part of Greenland and discuss our interpretation of results. Figure 1. SAR processed MCoRDS/I data taken near NGRIP on March 30, 2012