Shaking up Assumptions: Earthquakes Have Rarely Triggered Andean Glacier Lake Outburst Floods

• Published in: Geophysical Research Letters
• Main Authors: Joanne L. Wood, Stephan Harrison, Ryan Wilson, Adam Emmer, Jeffrey S. Kargel, Simon J. Cook, Neil F. Glasser, John M. Reynolds, Dan H. Shugar, Christian Yarleque
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2024
• Subjects: climate change; GLOF; natural hazards; Geophysics. Cosmic physics; QC801-809; permafrost
• Online Access: https://doi.org/10.1029/2023GL105578; https://doaj.org/article/5c291689651b42169daf04d9ba245f55

Abstract As the world’s glaciers recede in response to a warming atmosphere, a change in the magnitude and frequency of related hazards is expected. Among the most destructive hazards are glacier lake outburst floods (GLOFs), and their future evolution is concerning for local populations and sustainable development policy. Central to this is a better understanding of triggers. There is a long‐standing assumption that earthquakes are a major GLOF trigger, and seismic activity is consistently included as a key hazard assessment criterion. Here, we provide the first empirical evidence that this assumption is largely incorrect. Focusing on the Tropical Andes, we show that, of 59 earthquakes (1900–2021) the effects of which intersect with known glacier lakes, only one has triggered GLOFs. We argue that, to help develop climate resilient protocols, the focus for future assessments should be on understanding other key GLOF drivers, such as thawing permafrost and underlying structural geology.