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