Roundup: Glacier Collapse, Avalanche, and Loss

Collapse of Two Glaciers in Tibet After Surge-like Instability

From Nature: “Surges and glacier avalanches are expressions of glacier instability, and among the most dramatic phenomena in the mountain cryosphere. Until now, the catastrophic collapse of a glacier, combining the large volume of surges and mobility of ice avalanches, has been reported only for the 2002 130 × 106 m3 detachment of Kolka Glacier (Caucasus Mountains), which has been considered a globally singular event. Here, we report on the similar detachment of the entire lower parts of two adjacent glaciers in western Tibet in July and September 2016, leading to an unprecedented pair of giant low-angle ice avalanches with volumes of 68 ± 2 × 106 m3 and 83 ± 2 × 106 m3… Our findings show that large catastrophic instabilities of low-angle glaciers can happen under rare circumstances without historical precedent.”

Learn more about these rare occurrences here.

An ice-rock avalanche in the Kazbek region sheared off almost the entire Kolka Glacier and devastated the Genaldon valley in 2002 (Source: GRID Arendal/Flickr).


Five Army Personnel Missing After Avalanche Hits Siachen

From The Express Tribune: “At least five army personnel have gone missing after an avalanche hit an army base in world’s higgest battle ground Siachen. The Pakistan army has started a rescue operation in the area with the help of locals. Heavy machinery has also been sent to speed up the rescue operation. However, the army has still not confirmed any casualties… Avalanches and landslides are common at the Siachen Glacier during the winter and temperatures there can drop as low as minus 60 degrees Celsius. An estimated 8,000 troops have died on the glacier since 1984, almost all of them from avalanches, landslides, frostbite, altitude sickness or heart failure rather than combat.”

Read more about the avalanche at the Siachen Glacier here.

An estimated 8,000 troops have died on the Siachen glacier since 1984 (Source: junaidrao/Flickr).


3-D Stereo Images Reconstruct Changes in Antarctic Peninsula Glaciers

From Remote Sensing of Environment: “This paper presents detailed elevation and volume analysis of 16 individual glaciers, grouped at four locations, spread across the Antarctic Peninsula (AP). The study makes use of newly available WorldView-2 satellite stereo imagery to exploit the previously untapped value of archival stereo aerial photography. High resolution photogrammetric digital elevation models (DEMs) are derived to determine three-dimensional glacier change over an unprecedented time span of six decades with an unparalleled mean areal coverage of 82 percent per glacier… The analysis provides insight into one of the most challenging and data-scarce areas on the planet by expanding the spatial extent north of the AP to include previously un-studied glaciers located in the South Shetland Islands. 81 percent of glaciers studied showed considerable loss of volume over the period of record.”

Learn more about the study here.

View of the northern Antarctic Peninsula during IceBridge’s flight back from the Foundation Ice Stream, on Oct. 28 (Source: NASA/Flickr).