Greenland subglacial drainage evolution regulated by weakly connected regions of the bed

TitleGreenland subglacial drainage evolution regulated by weakly connected regions of the bed
Publication TypeJournal Article
Year of Publication2016
AuthorsHoffman, Matthew J., Andrews Lauren C., Price Stephen F., Catania Ginny A., Luethi Martin P., Gulley Jason, Ryser Claudia, Hawley Robert L., and Morriss Blaine F.
JournalNature Communications
Volume7
Pages13903
Date Published12/2016
Abstract / Summary

Penetration of surface meltwater to the bed of the Greenland Ice Sheet each summer causes an initial increase in ice speed due to elevated basal water pressure, followed by slowdown in late summer that continues into fall and winter. While this seasonal pattern is commonly explained by an evolution of the subglacial drainage system from an inefficient distributed to efficient channelized configuration, mounting evidence indicates that subglacial channels are unable to explain important aspects of hydrodynamic coupling in late summer and fall. Here we use numerical models of subglacial drainage and ice flow to show that limited, gradual leakage of water and lowering of water pressure in weakly connected regions of the bed can explain the dominant features in late- and post-melt-season ice dynamics. These results suggest that a third weakly connected drainage component should be included in the conceptual model of subglacial hydrology.

URLhttp://www.nature.com/articles/ncomms13903
DOI10.1038/ncomms13903
Journal: Nature Communications
Year of Publication: 2016
Volume: 7
Pages: 13903
Date Published: 12/2016

Penetration of surface meltwater to the bed of the Greenland Ice Sheet each summer causes an initial increase in ice speed due to elevated basal water pressure, followed by slowdown in late summer that continues into fall and winter. While this seasonal pattern is commonly explained by an evolution of the subglacial drainage system from an inefficient distributed to efficient channelized configuration, mounting evidence indicates that subglacial channels are unable to explain important aspects of hydrodynamic coupling in late summer and fall. Here we use numerical models of subglacial drainage and ice flow to show that limited, gradual leakage of water and lowering of water pressure in weakly connected regions of the bed can explain the dominant features in late- and post-melt-season ice dynamics. These results suggest that a third weakly connected drainage component should be included in the conceptual model of subglacial hydrology.

DOI: 10.1038/ncomms13903
Citation:
Hoffman, MJ, LC Andrews, SF Price, GA Catania, MP Luethi, J Gulley, C Ryser, RL Hawley, and BF Morriss.  2016.  "Greenland subglacial drainage evolution regulated by weakly connected regions of the bed."  Nature Communications 7: 13903, pp. 13903.  https://doi.org/10.1038/ncomms13903.