Assessing Mine-Induced Changes in the Gruvfonna Ice Cap Using Remote Methods

The Svalbard-based mining company, Store Norske (SNSK), currently produces about 1.2 million tonnes of coal annually. The most productive mine, Svea Nord, lies beneath the icecap Gruvfonna, which causes unique challenges. Typically, once a tunnel section has been successfully excavated the roof of the section is deliberately collapsed to reduce the load on the remaining coal seam. Since the mine's opening in late 2001, subsidence associated with large crevasses has been observed on the ice surface, which is believed to be caused by these collapses. However, many glaciers in Svalbard have been retreating and steepening in response to climate warming since the Little Ice Age, which can also be associated with increased crevassing. We use photogrammetry and airborne lidar data to quantify the vertical changes and appearance of crevassing on the ice cap and relate them to the mining activity. Data sources include: (i) SNSK mine survey data; (ii) Norwegian Polar Institute 1995 historical aerial photography; and (iii) lidar and aerial photograph data collected during a 2003 U.K. Natural Environment Research Council Airborne Remote Survey Facility campaign. An historical digital elevation model (DEM) is generated from the 1995 photos using ground control points extracted from the 2003 lidar DEM. By comparing changes in areas with and without mining activity we assess the impact of anthropogenic factors on the ice cap.