This series of time-lapse photographs collected between May 7 and June 30, 2014, revealed the rapid formation and drainage of an ice-dammed lake that forms along the western margin of White Glacier, approximately 1 km down-glacier of Anniversary profile (370 m a.s.l.).
Coincident with the lake drainage, it was observed that ice velocities at Anniversary profile, located 1 km up glacier, increased by approximately 250% above the previous flow rate. Three days later, glacier speeds peaked further up glacier at Moraine profile indicating the up-glacier propagation of ice acceleration (referred to as a kinematic wave) reached elevations of 870 m a.s.l.
It was not expected that such a large lake formed near the ice cave, and therefore it was quite a surprise for us when we analyzed the photographs in the summer of 2015. As you can tell from the images, we nearly lost the camera in the lake! After this exciting realization, we have moved the camera to higher elevations and increased the photo-sampling rate to 1 hour, which will enable us to distinguish whether speed-up events are a consequence of lake drainage, or whether ice motion destabilized the sub-glacial nature near the ice cave, allowing the lake to drain.