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

Abstract. The frontal flux balance of a medium-sized tidewater glacier in westernGreenland in the summer is assessed by quantifying the individual components(ice flux, retreat, calving, and submarine melting) through a combination ofdata and models. Ice flux and retreat are obtained from satellite data.Submarine melting is derived using a high-resolution ocean model informed bynear-ice observations, and calving is estimated using a record of calvingevents along the ice front. All terms exhibit large spatial variability alongthe ∼5 km wide ice front. It is found that submarine melting accountsfor much of the frontal ablation in small regions where two subglacialdischarge 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 bycalving. This result, however, is at odds with the limited presence oficebergs at this calving front – suggesting that melt rates in regionsoutside of the subglacial plumes may be underestimated. Finally, we arguethat localized melt incisions into the glacier front can be significantdrivers of calving. Our results suggest a complex interplay of melting andcalving marked by high spatial variability along the glacier front.

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Award ID(s):
Publication Date:
Journal Name:
The Cryosphere
Page Range or eLocation-ID:
911 to 925
Sponsoring Org:
National Science Foundation
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