Ground-penetrating radar data (50MHz) and internal reflection horizons along the central flowline of Ekström ice shelf, Dronning Maud Land, East Antarctica

• Main Authors: Oraschewski, Falk M, Moss, Guy, Koch, Inka, Ershadi, M Reza, Eisen, Olaf, Drews, Reinhard
• Format: Dataset
• Language: English
• Published: PANGAEA 2024
• Subjects: Antarctica; ANT-Land_2022_ReMeltRadar; ANT-Land_2023_ReMeltRadar; Bedrock elevation; DATE/TIME; Depth of internal reflection horizon; below ice surface; Distance; Dronning Maud Land; Ekström; Elevation of internal reflection horizon; flowline; GPR_GVN21-22; GPR_GVN22-23; ground-penetrating radar; Sensors & Software Inc.; pulseEKKO (R) [50 MHz]; Ice base elevation; Ice shelf; Ice thickness; Internal Reflection Horizon; IRH; LATITUDE; LONGITUDE; NEUMAYER III; Polar stereographic projection; X; Y; radar; Surface elevation; Two-way traveltime to ice base; Two-way traveltime to ice surface; Two-way traveltime to internal reflection horizon; East Antarctica; Ekström Ice Shelf; Neumayer; Annals of Glaciology; Antarc*; Antarctica Journal; Ice Shelf; Ice Shelves; Journal of Glaciology; The Cryosphere
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.965143; https://doi.org/10.1594/PANGAEA.965143

The internal stratigraphic structure of ice shelves forms by the interplay of ice dynamics, snow accumulation and basal melt. To infer accumulation and basal melt rates, we acquired a ground-penetrating radar profile (50 MHz; pulseEKKO (R) from Sensors & Software Inc.) along the central flowline of Ekström ice shelf, Droning Maud Land, East Antarctica. The data were collected in the two consecutive field seasons 2021/22 and 2022/23 with logistic support from Neumayer III station (Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, 2016). The profile starts about 5 km upstream of the grounding line and ends at a distance of 10 km to the ice shelf front, giving a total length of 129.3 km. Radar processing with ImpDAR (Lilien et al., 2020) encompassed trace averaging to equidistant spacing (10 m) and bandpass filtering (cut-off frequencies of 20 and 75 MHz). In addition, the REMA surface elevation (Howat et al., 2019) and the ice-ocean interface from BedMachine (Morlighem et al., 2017) were obtained along the profile line. The segments from both field seasons were connected without adjustments, because the vertical offset between IRHs is much smaller than the radar system's wavelength in ice (~3.4 m). The data shows the ice-ocean interface and continuous internal reflection horizons (IRHs) down to approximately 200 m depth. 4 IRHs were traced along the (nearly) entire length of the profile using a semi-automatic maximum tracking scheme (Koch et al., 2023).