Spatial extent of southeast Greenland firn aquifers detected by airborne radars, 1993-2018

Surface melt produces more mass loss than any other process on the Greenland Ice Sheet. In some regions of Greenland with high summer surface melt and high winter snow accumulation, the warm porous firn of the percolation zone can retain liquid meltwater through the winter. These regions of water-saturated firn, which may persist for longer than one year, are known as firn aquifers, commonly referred to as perennial firn aquifers. We use airborne ice-penetrating radar data from the Center for Remote Sensing of Ice Sheets (CReSIS) to document the extent of four firn aquifers in the Helheim, Ikertivaq, and Køge Bugt glacier basins. We select these sites because they have more than six repeat radar flight lines from 1993 to 2018. Our observations reveal decadal-scale expansion and interannual variability of the firn aquifers in response to high-melt years and decreasing cold content of the firn. This dataset contains detections of the four firn aquifers from the CReSIS Accumulation Radar data, collected from 2010 to 2018, and Radar Depth Sounder data, collected from 1993 to 2018. We use an open-source radar processing and interpretation toolbox to pick the detected firn aquifers in the data. The file all_detections.csv contains the latitude and longitude of the repeat radar flight lines, and the latitude and longitude of all detections of the four firn aquifers. Additionally, the associated collection year of the radar data is included. The other files contain the same data but broken into four individual files, one for each firn-aquifer site that was analyzed.