SNOWBALL EFFECT

I’m glad your article “The Science of Snow” (December) drew attention to avalanches. As the mother of a ski technician who works in Squamish, British Columbia, I’m very interested in the subject. My son knows everything about skis and boots, but he has also taken avalanche safety courses. Though they can’t be predicted completely, it’s important to know as much as we can about avalanches to keep mountains safe.

KAROLYN FRANCIS, NEW MARKET, ONTARIO