Isochronous information in a Greenland ice sheet radio-echo sounding dataset

The evaluation of ice sheet models is one of the pressing problems in the study of ice sheets dynamics. Here we examine the question of how much isochronous information is contained within the publicly available CReSIS Greenland airborne radio-echo soundings dataset. We identify regions containing isochronous reflectors using ARESP algorithms [Sime et al., 2011]. We find that isochronous reflectors are present within 36% of the CReSIS RES englacial data by location, and 41% by total number of data. Between 1000 and 3000 m in depth, isochronous reflectors are present along more than 50% of the dataset flight path. Lower volumes of cold glacial period ice also correspond with more isochronous reflectors. We find good agreement between ARESP and continuity index [Karlsson et al., 2012] results, providing confidence in these findings. Ice structure datasets, based on data identified here, will be of use in evaluating ice sheet simulations and the assessment of past rates of snow accumulation.