160 glacial lake outburst floods (GLOFs) across the Tropical Andes since the Little Ice Age

Abstract/Summary

Assessing the extent to which glacial lake outburst floods (GLOFs) are increasing in frequency in modern times and whether their incidence is driven by anthropogenic climate change requires historical context. However, progress on this issue is hampered by incomplete GLOF inventories, especially in remote mountain regions. Here, we exploit high-resolution, multi-temporal satellite and aerial imagery, and documentary data to identify GLOF events across the glacierized Cordilleras of Peru and Bolivia, using a set of diagnostic geomorphic features. A total of 160 GLOFs from 151 individual sites are characterised and analysed, tripling the number of previously reported events. We provide statistics on location, magnitude, timing and characteristics of these events with implications for regional GLOF hazard identification and assessment. Furthermore, we describe several cases in detail and document a wide range of process chains associated with Andean GLOFs.