A rockslide-generated tsunami in a Greenland fjord rang Earth for 9 days

作者：Kristian Svennevig, Stephen Hicks, Thomas Forbriger, Thomas Lecocq, Rudolf Widmer‐Schnidrig, A. Mangeney, Clément Hibert, Niels J. Korsgaard, Antoine Lucas, Claudio Satriano, R. E. Anthony, Aurélien Mordret, Sven Schippkus, Søren Rysgaard, Wieter Boone, Steven J. Gibbons, Kristen Cook, Sylfest Glimsdal, Finn Løvholt, Koen Van Noten, Jelle Daniel Assink, Alexis Marbœuf, Anthony Lomax, Kris Vanneste, T. Taira, Matteo Spagnolo, Raphael S. M. De Plaen, Paula Koelemeijer, Carl W. Ebeling, Andrea Cannata, William D. Harcourt, David G. Cornwell, Corentin Caudron, Piero Poli, Pascal Bernard, Éric Larose, Eleonore Stutzmann, Peter H Voss, Björn Lund, Flavio Cannavò, Manuel J. Castro, Esteban J. Chaves, Trine S. Dahl-Jensen, Nicolas De Pinho Dias, Aline Déprez, Roeland Develter, Douglas S. Dreger, Läslo Gerardus Evers, Enrique D. Fernández-Nieto, Ana M. G. Ferreira, G. J. Funning, Alice‐Agnes Gabriel, Marc Hendrickx, Alan L. Kafka, Marie Keiding, Jeffrey Taylor Kerby, Shfaqat Abbas Khan, Andreas Kjær Dideriksen, Oliver D. Lamb, Tine B. Larsen, Bradley Paul Lipovsky, Ikha Magdalena, Jean‐Philippe Malet, Mikkel Myrup, Luis A. Rivera, Eugenio Ruiz‐Castillo, Selina Wetter, Bastien Wirtz · 发表于：Science · 年份：2024 · DOI：10.1126/science.adm9247 · 被引用次数：71 · 研究领域：Landslides and related hazards、earthquake and tectonic studies、Seismic Waves and Analysis

Climate change is increasingly predisposing polar regions to large landslides. Tsunamigenic landslides have occurred recently in Greenland ( Kalaallit Nunaat ), but none have been reported from the eastern fjords. In September 2023, we detected the start of a 9-day-long, global 10.88-millihertz (92-second) monochromatic very-long-period (VLP) seismic signal, originating from East Greenland. In this study, we demonstrate how this event started with a glacial thinning–induced rock-ice avalanche of 25 × 10 6 cubic meters plunging into Dickson Fjord, triggering a 200-meter-high tsunami. Simulations show that the tsunami stabilized into a 7-meter-high long-duration seiche with a frequency (11.45 millihertz) and slow amplitude decay that were nearly identical to the seismic signal. An oscillating, fjord-transverse single force with a maximum amplitude of 5 × 10 11 newtons reproduced the seismic amplitudes and their radiation pattern relative to the fjord, demonstrating how a seiche directly caused the 9-day-long seismic signal. Our findings highlight how climate change is causing cascading, hazardous feedbacks between the cryosphere, hydrosphere, and lithosphere.