Waking up on Christmas day to a blanket of fresh white snow. Can we rely on the Swiss Alps to provide this snowy ideal?
We picked four ski resorts in Switzerland as a sample: two below 1,600 metres above sea level – Adelboden and Engelberg; and two above 1,600m – Arosa and Zermatt. We looked at how much snow they have had on Christmas Day since 1960, and whether there were times were there was no snow at all.
There is always snow on Christmas Day above 1,600m. Over the past 50 years, there was no clear decrease in the number of white Christmases at these Swiss ski resorts. However, the amount of snow is decreasing. In the graphic below a red dot shows a year where there was no snow on December 25.
It’s a trend that’s been observed by much deeper research too. The WSL Institute for Snow and Avalanche Research and the University of Neuchâtel published findings in September from a study using 11 MeteoSwiss weather monitoring devices in different alpine regions of the country. They analysed the data from 1970 up until 2015.
That study not only found that the annual maximum snow depth went down by an average of 25%, but also that the snow season is shorter. They found that the covering of snow now comes on average 12 days later in late autumn and melts away around 25 days earlier in spring, than it did in 1970. This means that the snow cover duration is declining twice as fast in spring as in autumn.
Changes to how long the snow lasts were found at all altitudes, although it is more immediately apparent to people where it can be seen, at lower altitude levels.
Whether the festive season will be snowy enough has long been a concern. A weather report from around 1911 provided by the MeteoSwiss declares: “Real winter cold and snow have become almost unknown things in the month of Christmas in recent years. There is no Christmas poem that speaks of cold, snow or ice that fits anymore.”
When was the last time you had a white Christmas?
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