Glacier surges and rapid terminus advance
A surging glacier or surge-type glacier refers to a glacier than exhibits a cyclic transition between a long quiescent phase (decades to years) and a short active phase (years to decades) of rapid ice movement. During this active phase, velocities can be over 100 times greater than during the quiescent phase (Meier and Post, 1969). The term 'surge' may also refer more generally to a period of rapid glacier advance that is not cyclic.
Remote sensing techniques are commonly used to observe surge characteristics such as the duration, magnitude of the velocity increase, and the return period of the surge (e.g. Mayer et al., 2011; Quincey et al., 2011). Several surges are visible in the animation below, where tributary glaciers to the Panmah Glacier (located in Central Karakoram National Park) advance and lead to deformed lateral and medial moraines.
Artificially-induced rapid glacier advance
A study of glaciers around Kumtor Gold Mine in Kyrgyzstan used fine-resolution satellite imagery to reveal a human-induced rapid glacier advance caused by the dumping of mine spoil supraglacially. This spoil was over 100 m thick in places and promoted enhanced internal ice deformation, leading to over 3 km of terminus advance for the Davidov Glacier. The animation below shows glacier terminus advance in a north-easterly direction. The glaciers advancing are covered in supraglacial spoil and are located in the lower left and in the centre of the animation.
See Rapid advance of two mountain glaciers in response to mine-related debris loading for more information on this glacier advance. A succinct summary is also available here.
Rapid glacier advance in the Everest Region
The animation below shows the flow of the Kangshung glacier. Flow was detected across the length of glacier by Quincey et al. (2009), with velocities of up to 36 m per year on the debris-covered area, and up to 42 m per year on the clean ice. Interestingly, a close look at the Chomo Lonzo Glacier reveals a period of rapid terminus advance (over 600 m) for approximately a decade, starting in 1987/1988. Recent glacier terminus advance has not been reported in this region before and the cause of this particular event is unknown. Feature tracking on remotely sensed imagery will allow the velocity of the advance to be determined and we are currently looking for similar events in the region.
You can read more about the techniques used to measure glacier movement in the Geomorphological Techniques (Online Edition) (ISNN 2047-0371) book chapter below:
- Mayer, C. Fowler, A.C. Lambrecht, A. and Scharrer, K. 2011. A surge of North Gasherbrum Glacier, Karakoram, China. Journal of Glaciology. 57(205), pp.904-916
- Meier, M.F. and Post, A. 1969. What are glacier surges? Canadian Journal of Earth Sciences. 6. pp.807-817.
- Quincey, D.J.Braun, M. Glasser, N.F. Bishop, M.P. Hewitt, K. and Luckman, A. 2011. Karakoram glacier surge dynamics. Geophysical Research Letters. 38(18), L18504.
Quincey, D.J. Luckman, A. and Benn, D. 2009. Quantification of Everest region glacier velocities between 1992 and 2002, using satellite radar interferometry and feature tracking. Journal of Glaciology. 55(192), pp.596-606.