Kvartære geosystemer

Dynamics of the North East Greenland Ice Stream

PhD candidate: Silje Smith-Johnsen

Supervision: Prof. Kerim H. Nisancioglu (UiB), Dr. Basile de Fleurian (UiB)

Project period: January 2016 -June 2019

This PhD project is part of the Ice2Ice project, which is funded by European Research Council

My PhD project focuses on understanding the dynamics of fast flowing ice streams, with North East Greenland Ice Stream (NEGIS) as an example. This ice stream is a unique feature and the only one in Greenland initiated far inland at the ice divide. It is hypothesized that the ice stream is triggered by a geothermal heat flux anomaly producing high temperatures and basal melt water in a place normally below freezing and slow. The basal regime of the Greenland ice sheet is unaccessible and therefore largely unknown. In order to predict future sea level rise from the Greenland Ice sheet, it is crucial to capture and reproduce the ice stream in ice sheet models.During my PhD project I will look into the basal processes and model the interactions between geothermal heat, temperature, subglacial hydrology, friction and sliding. The first part consist of idealized modeling of a synthetic ice stream and I will perform different experiments with geothermal heat flux anomalies. In the second and third part I will use what we learned from the idealized modeling and apply this to a more complex and realistic geometries of NEGIS. I use the Ice Sheet System Model (ISSM) developed by NASA, and will visit the model developers during my last year of the PhD at the Jet Propulsion Lab.