Glacier fluctuations and slope instabilities at Mount Meager Volcano: a historical approach.

Mount Meager is a volcanic complex located in SW British Columbia, Canada. It covers an area of about 225 km² and it supports 32 alpine glaciers (as reported in the GLIMS Glacier Database); it is known for the high landslide frequency and magnitude. In this study we document the present glacier morphology and activity at Mount Meager volcano, as well as landslide events. We digitized over 500 airphotos of the Mount Meager massif consisting of 8 time slices from 1947-2006 using SfM software to provide high-resolution orthophotos (0.42-1.13 m/pixel). The cartographic suitability of these datasets was tested by comparison with a Lidar DTM acquired in 2015-2016. By means of Lidar and orthophotos interpretation we mapped glacier outlines, moraines, landslide deposits, scars, and fractures. Glacier fluctuations were documented and related to geomorphic parameters: glacier length and basin area, headwall …