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Svartisen subglacial observatory

16.09.2014 | 15:30

Svartisen Subglacial Laboratory is situated under 200 m of ice in northern Norway. The laboratory provides a unique opportunity for direct access to the bed of a temperate glacier for the purposes of measuring sub-glacial parameters and performing experiments on the ice.

View map location of Engabreen.

Background
A subglacial intake was constructed beneath Engabreen, one of the valley glaciers draining western Svartisen, for hydro-electrical purposes. Permanent tunnels were made through the rock underneath the glacier and lead to access points that open directly at the ice-bed interface.

At one access point, it is possible to use hot water drilling to melt out ice tunnels in order to gain access to the glacier bed. It is then possible to sample ice that is unaffected by atmospheric processes, to be able to take much larger samples than is possible using boreholes and to leave experiments in place from one year to the next, easily gaining access to them again when necessary.

BBC visits Dr. Miriam Jackson at the Subglacial Laboratory.

 

A variety of projects have been completed in the laboratory by researchers from several different institutions. Several load cells have been installed beneath the ice and the anti-correlation between basal pressure and discharge has been examined, as well as the relation between load cell pressure and other parameters. An instrumented obstacle was installed at the bed surface and sliding speed, temperatures and stresses on the obstacle were measured. Using these data in a 3-d finite element model, it was possible to determine the viscosity parameter in the flow law, which was smaller than published values for clean ice.

Chemical and isotopic (d18O and dD) analysis of a two metre long basal ice core was performed to investigate the mechanisms by which different ice facies have been formed. These and other studies examining the basal stratigraphy of the ice suggest there is considerable water movement therein. Other projects include examining the fabric of the basal ice, tracing experiments to study the subglacial hydrology and examining the basal motion of glaciers over hard beds and soft beds.

 
Ice in the subglacial laboratory. Photo: Miriam Jackson

Facilities and equipment in the Subglacial Laboratory
The Svartisen Subglacial Laboratory includes the following facilities available for researchers:
* Fully-equipped living quarters with beds for up to 8 researchers in four bedrooms, kitchen with cooking facilities, dining/living area, bathroom including shower etc.
* Three laboratory rooms, freezer and workshop;
* Hot-water system for melting subglacial tunnels;
* Computer, electronics supplies, miscellaneous tools and heavy equipment;
*Telephone system throughout the tunnel system including at the main entrance, in the living area and in each of the laboratory rooms.

Subglacial workshop 25th - 26th March 2009 
The objective of the workshop was to bring together those who have worked in the subglacial laboratory previously with those who have done similar work elsewhere. As well as presenting and discussing new results, there was an opportunity to develop ideas for future projects and collaborations. The ice tunnel was opened for the workshop. Read more.

Map location of Engabreen:
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