Widespread glacier acceleration has been observed in
Greenland in the past few years associated with the thinning
of the lower reaches of the glaciers as they terminate in
the ocean. These glaciers thin both at the surface, from
warm air temperatures, and along their submerged faces
in contact with warm ocean waters. Little is known about
the rates of submarine melting and how they may affect
glacier dynamics. Here we present measurements of ocean
currents, temperature and salinity near the calving fronts of
the Eqip Sermia, Kangilerngata Sermia, Sermeq Kujatdleq and
Sermeq Avangnardleq glaciers in central West Greenland, as
well as ice-front bathymetry and geographical positions. We
calculate water-mass and heat budgets that reveal summer
submarine melt rates ranging from 0.7±0.2 to3.9±0.8md−1.
These rates of submarine melting are two orders of magnitude
larger than surface melt rates, but comparable to rates of
iceberg discharge. We conclude that ocean waters melt a
considerable, but highly variable, fraction of the calving fronts
of glaciers before they disintegrate into icebergs, and suggest
that submarine melting must have a profound influence on
grounding-line stability and ice-flow dynamics.