Winter motion mediates dynamic response of the Greenland Ice Sheet to warmer summers

Andrew Sole, Peter Nienow, Ian Bartholomew, Douglas Mair, Thomas Cowton, Andrew Tedstone, Matt A King

Research output: Contribution to journalArticlepeer-review

122 Citations (Scopus)
7 Downloads (Pure)

Abstract

We present ice velocities from a land-terminating transect extending >115 km into the western Greenland Ice Sheet during three contrasting melt years (2009–2011) to determine whether enhanced melting accelerates dynamic mass loss. We find no significant correlation between surface melt and annual ice flow. There is however a positive correlation between melt and summer ice displacement, but a negative correlation with winter displacement. This response is consistent with hydro-dynamic coupling; enhanced summer ice flow results from longer periods of increasing surface melting and greater duration ice surface to bed connections, while reduced winter motion is explicable by drainage of high basal water pressure regions by larger more extensive subglacial channels. Despite mean interannual surface melt variability of up to 70%, mean annual ice velocities changed by <7.5%. Increased summer melting thereby preconditions the ice-bed interface for reduced winter motion resulting in limited dynamic sensitivity to interannual variations in surface melting.
Original languageEnglish
Pages (from-to)3940-3944
Number of pages5
JournalGeophysical Research Letters
Volume40
Issue number15
Early online date6 Aug 2013
DOIs
Publication statusPublished - 16 Aug 2013

Keywords

  • Greenland ice sheet
  • ice sheet dynamics
  • ice sheet hydrology
  • global positioning systems
  • ice sheet melt

Fingerprint

Dive into the research topics of 'Winter motion mediates dynamic response of the Greenland Ice Sheet to warmer summers'. Together they form a unique fingerprint.

Cite this