Glacier detachment chain process in the Amney Machen Mountain

Glacial detachment is a new type of glacial hazard that has emerged recently．Since 2000, more than a dozen glacier detachments happened in the Tibetan Plateau．The Xiaomagou glacier of Amney Machen Mountain collapsed multiple times, in 2004, 2007, 2016 and 2019．Multi-sequence remote sensing images were used to analyze Xiaomagou glacier morphology and flow characteristics over the past 35 years．This combined with meteorological data and prior literatures revealed triggers for glacier collapse, glacier hazard potential in the future were identified．Previous glacier surges or slides, ice-rock avalanches at back slope, high temperature and/or precipitation, and glacier bed nature are all closely related to the occurrence of glacier collapse．Four large-scale ice-rock avalanches were observed in the glacier back slope zones from 2000-2011, which provided a material and dynamic basis for glacier collapses．The possibility of another glacier collapse in the next few years is extremely high．After the 2019 glacier detachment, Xiaomagou glacier has squirmed forward again．Newly developed unstable slope at the back edge of the glacier has been found. Increased ice crevasses were identified．Changes in slope ice velocity are likely related to relevant collapses．Understanding of triggers of Amney Machen glacier collapses, determination of potential hazard slope, together suggest that glacier morphology and movement characteristics should be monitored, remote sensing should be combined with meteorological data, to predict future disasters in a timely manner．