Extended Data Fig. 1: Leverett Glacier and proglacial stream.
From: Greenland melt drives continuous export of methane from the ice-sheet bed
a, Leverett Glacier (LG), with catchment boundaries38 outlined in grey; ‘SFJ’ denotes the Kangerlussuaq airport. b, Zoomed image of the LG, with the sampling site and portal marked by dots. c, Sensor deployment site during the early melt season, with the LG visible in the background; the image faces upstream. d, Sensor deployment site in late June; the image faces downstream. Also visible is the HydroC sensor inside a steel cage, during inspection and before redeployment. e, LG portal in late May, while still covered with both glacial and river ice. The photograph was taken one hour before the appearance of the glacial upwelling (see Supplementary Information 2b). The arrow marks the location of the chainsawed hole, shown in the inset (photograph taken on 10 May 2015). f, LG portal in mid-July 2015. Map images from USGS/NASA Landsat.
