Large spatial variations in the flux balance along the front of a Greenland tidewater glacier

The frontal flux balance of a medium-sized tidewater glacier in western Greenland in the summer is assessed by quantifying the individual components (ice flux, retreat, calving, and submarine melting) through a combination of data and models. Ice flux and retreat are obtained from satellite data. Su...

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Bibliographic Details
Published in:The Cryosphere
Main Authors: Wagner, Till J.W., Straneo, Fiamma, Richards, Clark G., Slater, Donald A., Stevens, Laura A., Das, Sarah B., Singh, Hanumant
Format: Article in Journal/Newspaper
Language:English
Published: 2019
Subjects:
Online Access:https://risweb.st-andrews.ac.uk/portal/en/researchoutput/large-spatial-variations-in-the-flux-balance-along-the-front-of-a-greenland-tidewater-glacier(2c442e34-a355-4291-a6b9-37abbf2cb3bf).html
https://doi.org/10.5194/tc-13-911-2019
https://research-repository.st-andrews.ac.uk/bitstream/10023/19647/1/Slater_2019_Cryo_Large_VoR_CCBY.pdf
Description
Summary:The frontal flux balance of a medium-sized tidewater glacier in western Greenland in the summer is assessed by quantifying the individual components (ice flux, retreat, calving, and submarine melting) through a combination of data and models. Ice flux and retreat are obtained from satellite data. Submarine melting is derived using a high-resolution ocean model informed by near-ice observations, and calving is estimated using a record of calving events along the ice front. All terms exhibit large spatial variability along the ∼ 5 km wide ice front. It is found that submarine melting accounts for much of the frontal ablation in small regions where two subglacial discharge plumes emerge at the ice front. Away from the subglacial plumes, the estimated melting accounts for a small fraction of frontal ablation. Glacier-wide, these estimates suggest that mass loss is largely controlled by calving. This result, however, is at odds with the limited presence of icebergs at this calving front-suggesting that melt rates in regions outside of the subglacial plumes may be underestimated. Finally, we argue that localized melt incisions into the glacier front can be significant drivers of calving. Our results suggest a complex interplay of melting and calving marked by high spatial variability along the glacier front.