Science and Nature :
IVAN COURONNE, AFP
3 DEC 2019
Scientists said Monday they had used a drone to observe the rapid fracturing and draining of a lake on the Greenland ice sheet, a phenomenon that may become more frequent as a result of climate change.
The ice sheet is typically about a kilometre thick (1090 yards), and during summer, it is normal for some of the surface to melt and form thousands of lakes.
Many of the lakes drain in just a few hours, creating vast openings at the base of the ice, up to a kilometre deep. Meltwater from surface streams continues to flow down them for the rest of the melt season, creating some of the world’s largest waterfalls.
Temporary meltwater lake, before and after drainage. (Thomas R. Chudley)
This process has been extremely difficult to observe firsthand, but a group of glaciologists from the Scott Polar Institute at the University of Cambridge were fortunate when they arrived at the Store Glacier in northwest Greenland in July 2018.