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The Chaos Canyon landslide, which collapsed on the afternoon of 28 June 2022 in Rocky Mountain National Park, presents an opportunity to evaluate instabilities within alpine regions faced with a warming and dynamic climate. Video documentation of the landslide was captured by several eyewitnesses and motivated a rapid field campaign. Initial estimates put the failure area at 66 630 m2, with an average elevation of 3555 m above sea level. We undertook an investigation of previous movement of this landslide, measured the volume of material involved, evaluated the potential presence of interstitial ice and snow within the failed deposit, and examined potential climatological impacts on the collapse of the slope. Satellite radar and optical measurements were used to calculate deformation of the landslide in the 5 years leading up to collapse. From 2017 to 2019, the landslide moved ∼5 m yr−1, accelerating to 17 m yr−1 in 2019. Movement took place through both internal deformation and basal sliding. Climate analysis reveals that the collapse took place during peak snowmelt, and 2022 followed 10 years of higher than average positive degree day sums. We also made use of slope stability modeling to test what factors controlled the stability of the area. Models indicate that even a small increase in the water table reduces the factor of safety to <1, leading to failure. We posit that a combination of permafrost thaw from increasing average temperatures, progressive weakening of the basal shear zone from several years of movement, and an increase in pore-fluid pressure from snowmelt led to the 28 June collapse. Material volumes were estimated using structure from motion (SfM) models incorporating photographs from two field expeditions on 8 July 2022 – 10 d after the slide. Detailed mapping and SfM models indicate that ∼1 258 000 ± 150 000 m3 of material was deposited at the slide toe and ∼1 340 000 ± 133 000 m3 of material was evacuated from the source area. The Chaos Canyon landslide may be representative of future dynamic alpine topography, wherein slope failures become more common in a warming climate. 

Abstract. Rock glaciers are a prominent component of many alpine landscapes andconstitute a significant water resource in some arid mountainenvironments. Here, we employ satellite-based interferometric syntheticaperture radar (InSAR) between 2016 and 2019 to identify and monitor activeand transitional rock glaciers in the Uinta Mountains (Utah, USA), an area of∼3000 km2. We used mean velocity maps to generate aninventory for the Uinta Mountains containing 205 active and transitional rockglaciers. These rock glaciers are 11.9 ha in area on average andlocated at a mean elevation of 3308 m, where mean annual airtemperature is −0.25 ∘C. The mean downslope velocity for theinventory is 1.94 cm yr−1, but individual rock glaciers have velocities ranging from0.35 to 6.04 cm yr−1. To search for relationships with climaticdrivers, we investigated the time-dependent motion of three rock glaciers. Wefound that rock glacier motion has a significant seasonal component, withrates that are more than 5 times faster during the late summer compared to therest of the year. Rock glacier velocities also appear to be correlated withthe snow water equivalent of the previous winter's snowpack. Our resultsdemonstrate the ability to use satellite InSAR to monitor rock glaciers overlarge areas and provide insight into the environmental factors that controltheir kinematics.