A skier has died after triggering an avalanche in the Denali National Park in Alaska on Thursday 2 May 2023. Park rangers and a helicopter were dispatched to the scene after witnesses described observing the skier trigger the avalanche while crossing an unnamed north-facing slope to the south of Jenny Creek at about 1.00 pm local time. They arrived to find the skier, later identified as Eric Walter, an employee of the park, who worked as a ski guide, had died in the avalanche.
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.
The Alaska Division of Parks and Outdoor Recreation has issued a warning to people travelling in avalanche-prone mountain areas in the state, as the warming spring weather makes snow-covered slopes more prone to avalanches at this time of year.
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