Ultra-wideband radar data upstream of the northern catchment of the Nioghalvfjerdsbrae (79°North Glacier), Northeast Greenland ...

• Main Authors: Franke, Steven, Helm, Veit, Steinhage, Daniel, Binder, Tobias, Jansen, Daniela
• Format: Dataset
• Language: English
• Published: PANGAEA 2022
• Subjects: AWI UWB; Greenland; Greenland ice sheet; Ice dynamics; radio-echo sounding; RES; Event label; Date/Time of event; File content; Documentation file; Binary Object; Binary Object File Size; Aircraft; P6_211_RESURV79_2018; POLAR 6; glacier; Ice Sheet
• Online Access: https://dx.doi.org/10.1594/pangaea.949391; https://doi.pangaea.de/10.1594/PANGAEA.949391

Here we present ultra-wideband radio-echo sounding data in northeast Greenland upstream of the northern catchment of the Nioghalvfjerdsbrae (79°North Glacier; 79NG). The radar data were acquired with AWI's multi-channel ultra-wideband (UWB) radar system in 2018. Most radar lines are located close to the ice divide; where ice flow velocity is almost zero and increases eastwards to as much as 15 meters per year. The survey was designed to closely investigate a set of folds. Twelve RES profiles were flown, at 7.5 km spacing, and oriented perpendicular to the 100° true North trend of the fold axes. The radar data has been used to decipher the regional ice-flow history of the northeastern Greenland Ice Sheet based on its internal stratigraphy. We applied a three-dimensional reconstruction of time-equivalent horizons to map folds deep below the surface that we then attribute to the deformation caused by now-extinct ice streams. We propose that locally this ancient ice flow regime was much more focused and reached ... : We present two radar data products: CSARP_qlook (unfocused) and CSARP_standard (SAR focused). For both, the files contain the radar data in the .mat format as well as pdf files of each segment with flight tracks and a radargram for each frame. Furthermore, we include an excel spreadsheet (rds_param_2018_Greenland_Polar6_FINEGIS.xls, see Further details link) which contains all radar data processing parameters.--CSARP_qlook: This product uses unfocused synthetic aperture radar processing for each channel and assumes that all reflections arrive at the receiver from nadir. The data are coherently stacked in slow time, and no correction for propagation delay changes is applied. Here, no motion compensation is applied. Finally, the signals from all eight channels are averaged incoherently. The range resolution is the same as for all other products. The trace spacing is ∼ 27–30 m.--CSARP_standard: This data product uses focused synthetic aperture radar processing (fk migration) on each channel individually. The ...