A ten-year record of supraglacial lake evolution and rapid drainage in West Greenland using an automated processing algorithm for multispectral imagery ...

• Main Authors: Morriss, Blaine F., Hawley, Robert L., Chipman, J.W., Andrews, L.C., Catania, Ginny A., Hoffman, M.J., Lüthi, M.P., Neumann, Thomas A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2013
• Subjects: glacier; Greenland
• Online Access: https://dx.doi.org/10.3929/ethz-b-000078369; http://hdl.handle.net/20.500.11850/78369

The rapid drainage of supraglacial lakes introduces large pulses of meltwater to the subglacial environment and creates moulins, surface-to-bed conduits for future melt. Introduction of water to the subglacial system has been shown to affect ice flow, and modeling suggests that variability in water supply and delivery to the subsurface play an important role in the development of the subglacial hydrologic system and its ability to enhance or mitigate ice flow. We developed a fully automated method for tracking meltwater and rapid drainages in large (> 0.125 km2) perennial lakes and applied it to a 10 yr time series of ETM+ and MODIS imagery of an outlet glacier flow band in West Greenland. Results indicate interannual variability in maximum coverage and spatial evolution of total lake area. We identify 238 rapid drainage events, occurring most often at low (< 900 m) and middle (900–1200 m) elevations during periods of net filling or peak lake coverage. We observe a general progression of both lake ... : The Cryosphere, 7 ...