Modelled 3D calving at Kronebreen, Svalbard, driven by tidal fluctuations and frontal melt

Abstract. Understanding calving processes and their controls is of importance for reducing uncertainty in sea level rise estimates. The impact of tidal fluctuations and frontal melt on calving patterns has been researched through both modelling and observational studies, but remain uncertain and may vary from glacier to glacier. In this study, we isolate various different impacts of tidal fluctuations on a glacier terminus to understand their influence on calving dynamics at Kronebreen, Svalbard, for the duration of one month. In addition, we impose frontal melt onto the calving front in order to allow for an undercut to develop over the course of the simulations. We find that calving events show a tidal signal when there is a small or no undercut but, after a critical point, undercut driven calving becomes dominant and drowns out the tidal signal. However, the relationship is complex and large calving events show a tidal signal even with a large modelled undercut. The modelled undercut sizes are then compared to observational profiles, showing that undercuts of up to c. 25 m are plausible. These findings highlight the complex interactions occurring at the calving front of Kronebreen and suggest further observational data and modelling work is needed to fully understand the hierarchy of controls on calving.