Most of the damage caused by the atmospheric rivers that caused flooding and heavy rains in British Columbia last summer was done in low-lying areas near the coast. They also left their marks on mountain peaks in Western Canada.
Mount Mackenzie, B.C. is one of the peaks. It is buried beneath dozens of millimetres of snow. A rain crust is a thick layer made of icy snow by an atmospheric river that drenched Revelstoke.
James Floyer is the Avalanche Canada forecasting team supervisor. He recently visited the mountain to do field work. He was able to ski up the slopes and make some reports. He cut off a small piece of the crust, and took it with him. He said that the smooth, slippery snow could provide the perfect platform for large avalanches to begin sliding if it is in the right conditions.
He said that the crust will form on the mountain’s south-facing slope, where sunlight helps to bond different layers of snow. Probably not. However, the north side is where the wind has loaded the mountain’s slab with new snow. There is a greater chance of a skier triggering avalanche. The reason is that the new slab has not had the time to meld with icy underlayer so the snow can easily move.
Avalanche Canada provides detailed forecasts of avalanche conditions for skiers, snowshoers and snowmobilers who spend time in mountainous backcountry areas. They also provide information to other people who might be at risk of falling. The non-profit organization employs more than 60 people in B.C., Alberta and Newfoundland.
As climate change affects global weather patterns, Mr. Floyer stated that rain and rain crusts are becoming more common winter alpine environments.
He also stated that warmer temperatures could cause more avalanches in springtime because moisture from melting snow can act as a fluid between snow layers, potentially triggering very destructive slides.
Experts in avalanche prevention and forecasting from the region believe climate change will cause more severe storms to hit Canada and affect snowpacks in Canada’s mountain ranges.
John Buffery, a senior B.C. avalanche officer, stated that we keep finding anomalies in heavy precipitation, wind, and snow events over the past couple of years. Ministry of Transportation and Infrastructure. These records are constantly broken.
Despite the increasing risk of avalanches, the number of Canadians who are killed by them is still very low. Avalanche Canada reports that slides have caused an average of 10 deaths per year over the past 10 decades. Since the 1990s, death rates have been declining steadily. According to the organization, there has been only one death by avalanche this winter season.
Avalanche Canada credits the rare incidence of fatalities to the growing number of people who take avalanche safety courses. More than 15,000 people This year, I took classes in the organization’s training program.
The way avalanche forecasters communicate with backcountry users is changing as a result of climate change.
In December, Mr.Floyer stated that Avalanche Canada warned against all travel to the Western Canada backcountry. It was only the second time he had ever heard of it, and after B.C. The third consecutive hit by the atmospheric river. (The organization also advised against backcountry travel at the start of the COVID-19 pandemic. However, this was to ensure that sporting injuries didn’t drain strained health care resources.
The agency will usually guide people to relatively safe terrain during adverse storms, rather than advise against doing any activity.
The confluence between the extreme weather event and the pressure on the roads system, along with something about COVID (and our concern that B.C.’s search-and rescue capacity might be diminished), made it difficult for us to assess the situation. Mr. Floyer stated that the situation was so dire that we felt that it was best to stay out of the backcountry.
This was an example of how variables in avalanche prediction are moving beyond traditional inputs like snowfall or wind.
Another The summer season is one of these variables.
Mr. Buffery said climate-change-related events including mudslides and forest fires have the potential to create new avalanche zones. Trees are a major source for stability for snow. Large avalanches are prevented from spreading by trees. Slopes can become more dangerous in winter if they are destroyed or removed.
Buffery said that weather events like the recent summer’s heat dome, which brought record high temperatures to Western Canada, could have an impact on avalanches. Some glaciers are found in avalanche zones close to highways because of the heat.
Mr. Buffery explained that it’s not just the winter issues that have affected avalanches. But, the overall impact of climate change has had a significant impact on the whole area. This is something we have been observing for the last few years.
As B.C. As B.C. adapts to changing weather conditions and mountain environments, snow slides will have a financial impact, according to Bruce Jamieson, a former University of Calgary professor who studied avalanches. He now works as a backcountry safety consultant.
Mr. Jamieson indicated that some of these costs will be covered. related to technology that prevents snow slides from closing down roads.
He stated that public tolerance for closings is declining and that governments are spending more money on remote avalanche control systems. These systems use explosives in order to create intentional slides to prevent dangerous snow accumulation.
Mr. Jamieson explained that climate changes have a less direct impact on avalanches than their influence on other natural disasters such as fires and floods.
It is easy to see a trend in wildfires. Larger fires and longer fire seasons. However, avalanches can be affected by weather patterns. These could include the type of snow falling and whether wind blows snow on certain slopes. Also, how snow bonds with icy rain crusts.
Mr. Floyer stated that avalanche forecasting relies on small changes in these factors, which shift with weather system.
Even if Canada’s mountain slopes change over time, he said that Avalanche Canada will continue to exist. Be able to adapt to changing conditions and keep backcountry users updated.
He acknowledged, however, that climate change could become a problem. Are we required to change the way we build our models. He stated that it was essential to be aware of the changes in order to move forward.
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