Hotspot beneath East Greenland and its impact on the Greenland ice sheet stability

In this project we intend to investigate the heat from the Earth’s interior beneath Greenland and its impact on the Inland Ice. We will use novel drone based magnetic measurements in North-east Greenland as proof-of-concept for modelling the heat flow and as foundation for improving melting models of the Greenland ice sheet.

A critical unknown in climate research is the future behaviour of the Greenland ice Sheet (GrIS). Irreversible changes may be occurring there, which will profoundly affect its contribution to global sea level rise and threaten vulnerable coasts.

Reliable predictions can only be made using fully-coupled ice sheet models (Church et al, 2013; Nick et al., 2013). Progress towards reducing the uncertainty of ice sheet modelling has been identified as crucial for projection of future sea level and thus society (Nowicki et al., 2013).

However, still little is known about the geothermal heat flux at the glacier bedrock, and how it affects dynamics of the major outlet glaciers in Greenland. Recent studies suggest the present-day hotspot under Iceland is thought to have been under eastern Greenland at somewhat 40 Ma BP (Khan et al., 2016) and speculate that the upwelling of hot material from the Iceland plume towards Greenland and northward may be ongoing, further heating the earth’s upper mantle.

If this is true, it may have a large influence on ice sheet and glacier flow dynamics, as a greater geothermal heat flux at the base of an ice mass will impact upon its internal thermal regime and the presence of basal melt water (Pollard et al, 2005).

The onset of increasing flow of the North East Greenland Ice Stream (the largest flow feature of the ice sheet) may be linked to a geothermal hotspot (Fahnestock, 2001). Therefore, this proposal aims to address key questions related to the understanding of changes in glacier dynamics and “in”-stability of glaciers in east Greenland through high quality, collaborative research using fieldwork, satellite altimetry and modelling studies.

To investigate influence of local heat flux anomalies on glacier dynamics, we propose to conduct airborne (with drone) magnetic measurement. Small anomalies in the strength of the geomagnetic field may be conducted with drone measurements and potential reveal location of a geothermal hotspot. We request for 500.000 kr. for fieldwork and a new commercially available and fully tested drone with long endurance (combustion-engine) that will serve in several projects.

Contact

Arne Døssing Andreasen
Senior Researcher
DTU Space
+4545 25 97 73