Landslides in Greenland from ArcticDEM time series analysis

Recent tsunamigenic landslides in the Arctic have highlighted the need for a better understanding of slope failures in remote Arctic regions. This study presents a systematic mapping of large landslides (area > 100,000 m²) that occurred in the past decade in Greenland using ArcticDEM data. We created surface elevation change maps from the DEM time series and classified landslides using an area-volume relationship. We detected two landslides in East Greenland, two moraine sediment landslides in Northwest Greenland, three landslides along talus slopes in Nuussuaq peninsula, and three landslides in Karrat Fjord, with volume loss ranging from 0.19 ± 0.02 million m³ and 50.5 ± 0.2 million m³. The ArcticDEM data enabled the first estimation of deposition of the 2016 Karrat landslide (6.34 ± 0.05 million m³), 32% larger than its depletion volume (4.8 ± 0.2 million m³) due to fragmentation. Our mapped landslides in Greenland from 2010 and 2020 provide valuable data for landslide risk management and landslide research.