Anomalous mass gain of a tidewater outlet glacier with rapidly thinning ice sheet margin in Greenland

In response to the general warming ocean-termination outlet glaciers of the Greenland ice sheet are generally thinning and retreating rapidly. However, the glacier system of Qajuuttap Sermia (also known as Eqalorutsit Kangilliit Sermiat), at the southwestern basin of the greenland ice sheet, shows a strongly contrasting and highly heterogenous dynamical behaviour. Detailed analysis of elevation changes (AeroDEM, GIMP, ArcticDEM) and front positions between the years 1985 and 2021 show slight but significant advance and thickening over at least the last 35 years, whereas its neighboring ocean- and land-terminating glaciers and more interestingly its three direct northwestern tributaries all show rapid thinning. The data indicates that effects of fjord geometry alone cannot explain this anomaly and we therefore further investigate potential reasons using operational continuous time series of solid ice flux (PROMICE) and surface mass balance from regional climate models (RACMO, MAR).