Evolution of Northwest Greenland Glaciers

In recent decades, tidewater glaciers in Northwest Greenland contributed
significantly to sea level rise but exhibited a complex spatial pattern of
retreat. Here, we use novel observations of bathymetry and water
temperature from NASA's Ocean Melting Greenland mission to quantify
the role of warm, salty Atlantic Water in controlling the evolution of 37
glaciers. Modeled ocean-induced undercutting of calving margins compared
with ice advection and ice-front retreat observed by satellites from 1985
to 2015 indicate that 35 glaciers retreated when cumulative anomalies in
ocean-induced undercutting rose above the range of seasonal variability of
calving-front positions, while 2 glaciers standing on shallow sills and
colder water did not retreat. Deviations in the observed timing of retreat
are explained by residual uncertainties in bathymetry, inefficient mixing
of waters in shallow fjords, and the presence of small floating sections.
Overall, warmer ocean temperature triggered the retreat, but calving
processes dominate ablation (71%). Wood et al 2018, under review in
Geophysical Research Letters