Landslides in a changing climate - Geohazards and benthic habitats in Northwest Greenland

On 17th of June in 2017, a rock avalanche in Karrat Fjord, Northwest Greenland, generated displacement waves with a runup of 10 m. Four lives were lost and the settlement Nuugaatsiaq (30 km away) was evacuated and permanently abandoned. Rock slope failures on the Greenland coast are not unusual. Vaigat (150 km south, Fig. 1 below) has experienced at least two large tsunamis in the last 70 years. In addition to the life-threat, landslides drastically change the seafloor morphology conditioning the ecosystem evolution, with subsequent implications for the local economy. However, the long-term history, frequency, and control factors of the landslides in Northwest Greenland are not fully understood which hampers the ability to identify high-risk locations.

The study
A direct link between the current trend towards warm climate and decreasing slope stability has recently been suggested based on an increasing incidence of landslides in polar marginse. In addition to the common triggers of landslides, increased precipitation, permafrost degradation and rapid isostatic rebound become determining preconditioning factors for slope instability in polar margins. However, the climate link to the landslide occurrence remains to be evaluated in examples from the geological past.

The detailed study of the mass transport deposits in Karrat Fjord and Vaigat has the potential to reveal the frequency and magnitude of landslides (or rock avalanches) and tsunamis in West Greenland, their relation to climate change and the variability of the Greenland ice sheet, and their impact on benthic habitats. Thus, we propose to utilize the nearshore landslide record in West Greenland, and published climate studies, to bridge knowledge gaps on climate-related triggers for slope instability, and the implications of the current trend of climate change.

Read more her https://eng.geus.dk/nature-and-climate/sea/project-landslides-in-a-changing-climate