Instituttseminar ved Faezeh Nick fra UNIS

Calving of icebergs is an important mechanism for rapidly transferring mass from the polar ice sheets into the surrounding ocean. Recent observations have shown that changes in calving rate can greatly reduce the extent of floating ice shelves and ice tongues, potentially resulting in increased discharge from the interior. Over the past two decades, ice loss from the Greenland Ice Sheet increased as a result of both increased surface melting and ice discharge through the narrow outlet glaciers. Increased ice discharge is controlled by the acceleration of ice flow and subsequent thinning of fast-flowing marine terminating outlet glaciers. Quantifying the future dynamic contribution of such glaciers to sea-level rise remains a major challenge because outlet glacier dynamics are not well understood.

Here I first introduce different types of calving and calving laws and how we implement a physical calving law in a flow-line model. Then I present a glacier flow line model that includes a fully dynamic treatment of marine termini to simulate behaviour of four major outlet glaciers in Greenland (Helheim, Kangerdlugssuaq, Petermann and Jakobshavn Isbræ), which provides insights into the role of ice-ocean interaction and fjord geometry and improves our ability to predict future ice sheet change.

Forfriskninger i "Steinbiten" etter foredraget.