The glacial processes that induce seismic events (internal deformation, sliding at the base, disintegration at the calving front, drainage of supra-glacial lakes) are all integral to the overall dynamics of glaciers, and seismic observations of glaciers therefore provide a quantitative means for monitoring changes in their behavior over time. Long-term seismic monitoring of the Greenland Ice Sheet will contribute to identifying possible unsuspected mechanisms and metrics relevant to ice sheet collapse, and will provide new constraints on Ice Sheet dynamic processes and their potential roles in sea-level rise during the coming decades. GLISN will provide a new, fiducial reference network in and around Greenland for monitoring these phenomena in real-time, and for the broad seismological study of Earth and earthquakes.
The GLISN development is focused on 1) upgrading equipment and adding real-time telemetry to existing seismic infrastructure in Greenland, 2) installing new, telemetered, broadband seismic stations on Greenland’s perimeter and ice sheet, 3) coalescing telemetry from existing real-time, high-quality, broadband stations in and around Greenland into the GLISN network, and 4) distributing the real-time data to users and international data centers. In collaboration with GLISN, the Global Centroid Moment Tensor Project will provide a near-real-time catalog of glacial earthquakes. The development incorporates state-of-the-art broadband seismometers and data acquisition, Iridium and local Internet, power systems capable of autonomous operation throughout the polar year, and stable, well-coupled installations on bedrock and the Ice Sheet. GPS will also be installed at sites on the Ice Sheet. All data from GLISN will be freely and openly available to anyone in real-time, without restriction.
- Programme Area 3: Energy Resources