Projects per year
Abstract
Warm, subtropical-originating Atlantic water (AW) has been identified as a primary driver of mass loss across the marine sectors of the Greenland Ice Sheet (GrIS), yet the specific processes by which this water mass interacts with and erodes the calving front of tidewater glaciers is frequently modelled and much speculated upon but remains largely unobserved. We present a suite of fjord salinity, temperature, turbidity versus depth casts along with glacial runoff estimation from Rink and Store glaciers, two major marine outlets draining the western sector of the GrIS during 2009 and 2010. We characterise the main water bodies present and interpret their interaction with their respective calving fronts. We identify two distinct processes of ice–ocean interaction which have distinct spatial and temporal footprints: (1) homogenous free convective melting which occurs across the calving front where AW is in direct contact with the ice mass, and (2) localised upwelling-driven melt by turbulent subglacial runoff mixing with fjord water which occurs at distinct injection points across the calving front. Throughout the study, AW at 2.8 ± 0.2 °C was consistently observed in contact with both glaciers below 450 m depth, yielding homogenous, free convective submarine melting up to ~200 m depth. Above this bottom layer, multiple interactions are identified, primarily controlled by the rate of subglacial fresh-water discharge which results in localised and discrete upwelling plumes. In the record melt year of 2010, the Store Glacier calving face was dominated by these runoff-driven plumes which led to a highly crenulated frontal geometry characterised by large embayments at the subglacial portals separated by headlands which are dominated by calving. Rink Glacier, which is significantly deeper than Store has a larger proportion of its submerged calving face exposed to AW, which results in a uniform, relatively flat overall frontal geometry.
Original language | English |
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Pages (from-to) | 1457-1468 |
Journal | Cryosphere |
Volume | 8 |
Issue number | 4 |
DOIs | |
Publication status | Published - 08 Aug 2014 |
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Dive into the research topics of 'Ice–ocean interaction and calving front morphology at two west Greenland tidewater outlet glaciers'. Together they form a unique fingerprint.Projects
- 3 Finished
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Investigating Meltwater Flow Beneath the Greenland Ice Sheet using a Multi-tracer Approach
Hubbard, A. (PI)
Natural Environment Research Council
01 May 2011 → 30 Apr 2015
Project: Externally funded research
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A Holistic Model of Outlet Calving, Dynamic Acceloration and Drawdown for the Greenland Ice Sheet
Hubbard, A. (PI), King, M. (CoI) & Vieli, A. (CoI)
Natural Environment Research Council
01 Jun 2009 → 31 May 2011
Project: Externally funded research
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Dynamic Response of the Greenland Ice Sheet to Climate Forcing using a geophysical, Remote sensing and Numerical Modelling Framework
Hubbard, A. (PI) & Quincey, D. J. (CoI)
Natural Environment Research Council
01 Mar 2009 → 31 Jan 2013
Project: Externally funded research