Seismic waves passing through the ground near Longyearbyen in the Adventdalen valley, Svalbard, Norway have been slowing down steadily over the past three years, most likely due to permafrost warming in the Arctic valley.
The trend, reported in a new study published in Seismological Research Letters, demonstrates how seismic monitoring can be used to track permafrost stability under global climate change. The study is part of a focus section in an upcoming issue of the journal on Arctic and Antarctic seismology.
Julie Albaric of the University of Bourgogne Franche-Comté, while employed at NORSAR (Norway), and colleagues used data collected from a variety of seismic networks and active seismic experiments to learn more about the seismic environment of the Adventdalen valley of Svalbard, and to understand more about the dynamics of permafrost in the region.
The researchers were able to detect seasonal variations in seismic wave velocity, which they attribute to changes in the ice content of shallow (2 to 4 meters deep) permafrost. Seismic waves move faster through solid materials like rock and ice, and slower through more liquid or softer material.
Read more at Seismological Society of America
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