Drone images display the Greenland ice sheet turning more keyed as it fractures.
The second-largest ice sheet of the world and the single most significant contributor to global sea-level rise is probably turning keyed because of fractures growing in response to faster ice flow and more meltwater forming on its surface. By using customized drones (strong enough to stand against the ultimate Arctic conditions), researchers led by the University of Cambridge built the first drone-based observations of how cracks cause catastrophic lake drainages, in which vast quantities of surface water are shifted to the sensitive environment under the ice.
The study was disclosed in the Proceedings of the National Academy of Sciences, displays how the water is transferred and how the ice sheet reacts. The researchers had found that inflowing meltwater extended the lake and drainage started when the edge of the lake divided a fracture, that was formed before one year.
Every summer, thousands of lakes make on the Greenland Ice Sheet as the weather gets warm. Many of these lakes can cleanse in just a few hours, by forming caverns that are known as moulins, by which water descends to the bottom of the ice sheet. These cavities typically remain open for the leftover of the melt season, as meltwater from streams and rivers on the surface descends under the ice. Given that the ice sheet is a kilometer or thicker, the flow of water into the moulins may be the largest waterfall in the world.
While producing the research from a camp on Store Glacier in northwest Greenland, the team vouched how this fracture turns active and how it disclosed 500 meters further into the lake, causing the lake to drain rapidly. With multiple drone flights, the team was able to document the flowing of the water into the fracture and the water’s following pathway beneath the ice. In a detailed recast of the event, which is seldom observed directly, the team, which also included researchers from Aberystwyth and Lancaster Universities, displayed how the meltwater causes the composition of new fractures, as well as the propagation of dormant fractures.