Greenland Marine-Terminating Glacier Retreat Data

The thinning, acceleration, and retreat of Greenland glaciers since the mid-1990s has been attributed to the enhanced intrusion of warm Atlantic Waters (AW) into fjords, but this assertion has not been quantitatively tested on a Greenland-wide basis or included in numerical models. Here, we investigate how AW influenced the retreat of 226 marine-terminating glaciers by combining ocean modeling, remote sensing, and in-situ observations. We identify 74 glaciers standing in deep fjords with warm AW that retreated when ocean warming induced a 48% increase in glacier undercutting that controlled 62% of the glacier mass loss in 1992-2017. Conversely, 27 glaciers calving on protective, shallow ridges and 24 glaciers standing in cold, shallow waters did not retreat; and 10 glaciers retreated when their floating sections collapsed. The mechanisms of ice front evolution remain undiagnosed at 87 glaciers with no ocean and bathymetry data, but these glaciers only account for 16% of the retreat. Projections of glacier evolution that exclude ocean-induced glacier undercutting may underestimate future mass losses by at least a factor two.

 

In this dataset, we present data for 226 glaciers over the time period 1985-2017. In particular, we provide estimates of glacier geometry, ocean thermal forcing on the continental shelf and at the glacier terminus, ice velocity, ocean-induced melt, and thinning-induced retreat. Most of the data is compiled in a netCDF file for each of the 226 glaciers investigated durign the study period, with the exception of ice front boundaries for the years 1985-2019 digitized from Landsat 5, 7, and 8 imagery, which we provide in a single shapefile. In addition, we include a PDF which displays the data enclosed for each glacier.