Saturday 5 January 2019

Avalanche kills skier in British Colombia.

A 42-year-old man has died in an avalanche in British Colombia. The incident happened at about 3.00 pm local time on Thursday 3 January 2019, near Pebble Creek in the Pemberton Valley. The man is described as coming from Squamish, but has not yet been named. He was with a number of other skiers at the time of the incident, but was the only one caught in the avalanche. His companions were able to reach him quickly, as he was wearing an emergency beacon, but were unable to revive him.

The approximate location of the 3 January 2019 British Colombia avalanche. Google Maps.

Avalanches are caused by the mechanical failure of snowpacks; essentially when the weight of the snow above a certain point exceeds the carrying capacity of the snow at that point to support its weight. This can happen for two reasons, because more snow falls upslope, causing the weight to rise, or because snow begins to melt downslope, causing the carrying capacity to fall. Avalanches may also be triggered by other events, such as Earthquakes or rockfalls. Contrary to what is often seen in films and on television, avalanches are not usually triggered by loud noises. Because snow forms layers, with each layer typically occurring due to a different snowfall, and having different physical properties, multiple avalanches can occur at the same spot, with the failure of a weaker layer losing to the loss of the snow above it, but other layers below left in place - to potentially fail later.

Diagrammatic representation of an avalanche, showing how layering of snow contributes to these events. Expedition Earth.

See also...
Follow Sciency Thoughts on Facebook.