Why no two snowfalls are ever quite the same
By Paul Wilson
Originally published in ML Winter 2012.
“There is no material of engineering significance that displays the bewildering complexity of snow.” This surprising statement was made by two Canadian “snowologists,” D.H. Male and D.M. Gray, in their classic anthology of snow studies, The Handbook of Snow, first published in 1981.
But when you think about it, it’s not all that surprising. Unlike rain, which is essentially water, snow falls in infinite varieties of crystalline forms, and when it accumulates on the ground, it immediately begins to “set” – or undergo further complicated changes as a result of wind, gravity, temperature shifts, land gradient, and other stresses. It’s probably a myth that no two snowflakes are alike – at least, there’s no way of proving it – but it’s safe to say that no two snowfalls are ever quite the same. Anyone who has ever shoveled a driveway or shot a hill knows how true that is.
Snow has always fascinated us. In the early twentieth century, a man known as Snowflake Bentley pioneered the art of photographing snowflakes. Then, in the 1960s, a pair of intrepid Japanese snowologists developed a system for classifying snowflakes that identifies 80 different types.
Some are tiny crystals that, under a microscope, resemble hexagonal or prism-like plates. Others form six-pointed star-shaped plates; still others are called “stellar dendrites” because they have “tree-like” branches – the “classic” shape we all associate with snowflakes. Other varieties of dendrite resemble ferns, still others are more like hollow crystals or needles, or tiny columns with caps. There are triangular snow crystals and twelve-sided snowflakes, or odd, asymmetrical structures called “bullet rosettes.” Sometimes snow combines to produce large fluffy flakes. Or it can come down as soft snow pellets called “graupel.” In any given snowfall, depending on the climate conditions, certain types predominate, but when they land on the ground, they interlock to form a blanket that produces a unique surface on which to ski, board, toboggan, or snowshoe.
The changeable nature of snow has given rise to the belief that the Inuit, for instance, have dozens of words for it. In 1984, The New York Times lamented the fact that reporters covering the winter Olympics in Sarajevo had only one word to describe “the white stuff,” whereas the Inuit peoples had over a hundred. In fact, it’s just another one of the many myths about this strange substance. Depending on which of the Inuit languages you look at, the peoples who live in Arctic regions have no more words for snow than we do in English.
Perhaps the richest snow vocabulary can be found among skiers and snowboarders, who have given us colourful ways of describing “gnarly” conditions like Ball Bearings, Blue Ice, Boilerplate, Chop, Corduroy, Corn (a grainy, crystalline snow that sometimes appears in the spring) Crud (wet, lumpy churned-up snow that makes turning hard), Death Cookies (locally also known as “Beaver Balls” – frozen or solid clumps of snow that is often the result of incompetent snow-making or grooming) and “Frozen Chicken Heads” (a result of freezing slush) and dozens more. All fitting tributes to a fascinating substance that we are still trying to get a handle on.