Bad Year for Avalanches. But Just How Bad? The Numbers Tell

When ski patroller Andrew Entin was killed in an avalanche Tuesday on his normal control route at Squaw Valley, it brought the season total in North America to 38 deaths. If you consider the tragedy of even one person lost, it’s a sad and shocking number. But how does it stack up to other years? Worse? It sure seems like it.

In fact, the 21 deaths in September was the worst December in the last 10 years. The rain layer that plagued the West in the early season really took its toll–only two other months in the last 10 years have been worse: January 2008, with 25, and January 1999, with 22. And as you can see from the chart at right, which shows the cumulative season total by month, the early season continued to be bad, bad, bad. It wasn’t until the snowpack settled down later in January (and backcountry riders got the message) that things calmed down.

As always, click to enlarge the charts.

When you compare this season to the past two seasons and the 10-year average (again, looking at cumulative totals by month), you can see that it’s ahead of two years ago, one of the least-bad seasons on record, and slightly ahead of the historical average. Of course, this season’s March total is only calculated through March 5.

And what of seasonal totals? As you can see, the numbers bounce around quite a bit, from 26 two years ago to 58 last season. A moving average would tell us more, but I don’t yet have access to that data. Intuition and personal experience show the numbers move with the amount of snow we get, but it would be helpful to have or create a national or regional snowfall index against which we could compare these numbers.

The real question is how avalanche fatalities compare to the user-days in the snow. Unfortunately, backcountry and sidecountry traffic is almost impossible to gather. If any of you snow and number geeks have any insight, drop a line.

Data provided by avalanche.org. Charts are ©The Adventure Life. You are welcome to use them as long as you provide credit and a link back to www.theadventurelife.org.