| Summary: | In July 2016 we collected simultaneous field measurements of supraglacial river discharge and localized ice motion on the southwest Greenland Ice Sheet ablation zone. The measurements were obtained upstream of a major moulin, enabling study of how supraglacial meltwater runoff influences subglacial hydrology and ice motion. Field operations were carried out from 5-14 July 2016, with 168 consecutive hourly measurements of supraglacial river discharge collected 6-13 July using a SonTek RiverSurveyor M9 Acoustic Doppler Current Profiler (ADCP). A Tyrolean cableway was suspended over the river to safely and repeatedly tow the ADCP back and forth across the channel. A total of 847 ADCP transects were acquired, of which 677 later passed rigorous quality-assurance screening and were used to compute 174 hourly in situ discharge measurements. The full-resolution transects of ADCP velocity data are provided here. At the same time, simultaneous measurements of ice surface motion were collected every 5 seconds using a Trimble R7 Global Positioning System (GPS) receiver and Trimble Zephyr Geodetic antenna anchored in the ice (67.048°North (N), -49.018 ° West (W), elevation 1211.43 meters (m)). On-ice kinematic GPS positions were later estimated using carrier-phase differential processing relative to a bedrock mounted base station (67.150°N, -50.058°W, elevation 581.19) and final International GNSS Service satellite orbits. The full resolution GPS data are provided here. Used together, the paired datasets enable study of the interaction of supraglacial meltwater moulin input with local ice sheet motion. When using these data please cite the 2021 research article (Smith et al., "Supraglacial river forcing of subglacial water storage and diurnal ice sheet motion", Geophysical Research Letters, 2021). When citing the ADCP hydrographic data collection method please cite the original article describing this measurement methodology (Smith et al., Direct measurements of meltwater runoff of the Greenland ice sheet surface, Proceedings of the National Academy of Sciences (PNAS), 2017 https://www.pnas.org/content/pnas/114/50/E10622.full.pdf) [Note: An additional 72 h of ADPC discharge data from the same site appear in the Supplemental Information of that paper] An R script, saveFiles.R is included here to access the files. Please get in touch with support@arcticdata.io for additional help in downloading files in this dataset.
|
|---|