Volume changes in the glaciers and ice caps of west Greenland since the Little Ice Age (1890 - 2014)

Local glaciers and ice caps in Greenland are important contributors to global sea level rise yet are relatively understudied. This study has mapped the extent of 2907 glaciers and ice caps in west Greenland and calculated glacier-specific equilibrium line altitudes during the Little Ice Age (LIA). Surface lowering and volume loss between the LIA, which is taken as 1890, and 2014 reveals that there has been at least 184 ± 29 km3 of volume loss from west Greenland glaciers and ice caps at a rate of 1.5 ± 0.2 km3/year, since the LIA. The contribution to sea level rise from these glaciers has been 0.47 ± 0.07 mm since the LIA. The volume loss observed was lower than expected, when compared to NE Greenland for example, and the average rate of loss for the period was only equivalent to 5% of the rate of loss for all glaciers and ice caps in Greenland not connected to the main ice sheet.
Statistically significant relationships with volume loss were found for both latitude and coastal proximity across glaciers and ice caps in west Greenland, between the LIA and 2014. Both of the observed relationships produced weak negative correlations; as the distance from the coast increased, volume loss decreased (r = -0.041), as latitude increased, volume loss decreased (r = - 0.071). The volume loss seen from west Greenland glaciers on a centennial scale has a sea level rise contribution comparable to the three largest outlet glaciers of the Greenland Ice Sheet. This indicates that glaciers and ice caps in west Greenland are significant in terms of the total sea level rise contribution from Greenland land-ice, in line with trends predicting that local glaciers and ice caps will become a major control on sea level rise over the 21st Century.