The Hush of Snow
By FARHA GUERRERO
Most of us who recreate on snow, can’t get enough of the white stuff.
I still remember my fascination years ago when I traveled to Whistler as a tourist, watching the rain turn into snow like magic on my car’s windshield, somewhere north of Squamish on highway 99.
It seemed like something out of storybook to see rain drops morph into ice crystals and then into huge snowflakes, whitening everything in sight and even dampening the sound of the passing cars.
What I didn’t know then, was that this magic, is a marvel of physics, thermodynamics and chemistry, the interplay between temperature, wind and water vapour. Snow, after all, is not frozen rain; that would be sleet. Snow is formed in snow clouds and begins as water vapour freezes into ice crystals which form into hexagonal prisms. It then grows and develops, each developing its own ornate patterns.
And yes it’s true, there is no one snowflake exactly alike. It’s something to think about the next time you catch one in your mittens or stick out your tongue to taste one. It is estimated that more than one quadrillion snowflakes fall every year in a places like Canada, that’s about the same amount of stars in the universe.
I never considered this before, but is snow really white?
Just like salt and sugar, snow is actually transparent but it appears white because light is scattered; and this is due to a diffuse reflection of the whole spectrum of light within its tiny crystals. Our eyes perceive the whiteness because the wavelengths of light are bending. And as snow evolves on the ground, changes in its morphology, shape and spectrum take place.
Skiers know this well, and there is no shortage of lingo to describe the many types of snow that exist on the mountain: powder, crud, corn, champagne, windblown, slush, heavy, wet, death cookies, punchy to name a few — words that describe its ever changing metamorphic state and freeze cycles.
What would be dreamy snow for one, might be a bother for another. Just ask a cross country skate skier what snow they would prefer, and do the same with one of those skiers with very fat skis. And it might be worthwhile gently reminding a tourist with snowshoes every now and then that when the snow is hard packed they might be better off using crampons. Save the snowshoes for deep fluffy snow.
I’ve always wondered if the hush of snow is true.
Does fresh snow really quiet our surroundings? The answer is yes, fresh snow is quieter because of the large amount of pores on its surface, which in this way, acts like acoustic ceiling tiles or carpet. The snow loses its hush quality when the pores close after the snow hardens. So it’s worthwhile going for a silent walk with freshly fallen snow, before the snow plowers show up on the Whistler Valley trail.
But no other snowflake fact can be more interesting at least to me, than the average speed that it takes for a one to travel to us.
Snowflakes journey at roughly five kilometres an hour, but if they accumulate water on their way down, they may travel up to 15km. Since most fall at this slower speed, it can take about an hour for snowflakes to travel from a cloud to the ground. Just like waves in the ocean that travel long distances to reach the shores of anxious surfers thanks to that initial faraway wind, we too can be thankful for the time and energy that the snow journeys downwards to us, and the science that makes the perfect white stuff.
After all, what would we do in Whistler without it.
The Physics of Snow, presented by Dr. Benny Bach, Youtube.