Inventory and changes of rock glacier creep speeds in Ile Alatau and Kungöy Ala-Too, northern Tien Shan, since the 1950s

Abstract. Spatio-temporal patterns related to the viscous creep in perennially frozen sediments of rock glaciers cold mountains have rarely been studied outside densely populated European Alps. This study investigates spatial and temporal variability glacier movement Ile Alatau Kungöy Ala-Too mountain ranges, northern Tien Shan, a region with particularly large fast glaciers. Over more than 3000 km2, an inventory slope movements was constructed using number radar interferograms high-resolution optical imagery. The includes 900 landforms, which around 550 were interpreted as Out active inventoried, 45 are characterized by rate motion exceeding 100 cm/a. From these we selected six (Gorodetzky, Morenny, Archaly, Ordzhonikidze, Karakoram, Kugalan Tash) them detail offset tracking between repeat aerial images historical modern satellite data. Two showed steady increase decadal surface velocities from 1950s onwards, speeds being roughly 2 4 times higher recent years compared 1960s. Three similar accelerations over last 1 decades but also phases increased development indicates possible significant current sediment ice fluxes through implies that their material transport might gain geomorphodynamic importance relative glaciers, assuming latter decreases together regional shrinkage. demonstrates how air image archives exploited construct one longest decennial series currently available. Our results line findings Europe about increasing atmospheric warming underline local such overall response.