If you ever need a lesson in physics, and on the effects of the sheer number of variables that hide right in front of you in the everyday, you don’t have to look any further than a snowdrift.
Sunday, when the wind came up high and sharp in the early afternoon, you could get the unsettling experience of cars winking into and out of sight in front of you, one moment taillights, the next, nothing but a white and abrupt wall, the blowing snow lit solid by the bright sunlight.
There are a thousand changes — the odd topographic lines, strangely built along the tops of static drifts, where you can’t decide whether one snowflake caught and the rest built up around it, or whether the wind has carved the drift away cleanly until, again, one single recalcitrant flake was too entrenched to move and generated a growing line built on its fragile resistance.
There are the drifts themselves, hard on some edges, collected soft snow on others, and deep in the woods behind Windsor Lake, most of the snow completely untouched, there is a wobbly spirograph pattern where, when you track it right back, a small ball of light snow fell from a tree branch, and the wind has carried it around in bounces, leaving a trail like a small and confused animal.
Look at something like that, and you almost have to let it burn its way straight into your memory: it will never happen again — at least, it will never happen again in precisely that way, the little divot of snow pitched back and forth by the variable direction of winds caught in a clearing skirted by heavy spruce.
Even so, every roil of snow is explainable afterwards, every cornice and cut-edge and lined drift, every bit of it a practical equation of force, mass, direction, friction and the unique shape of individual flakes.
Some of it is simple: watch the wind-blown snow come out over the high edge of the plowed roadway, and you see an almost-perfectly round roll of air-caught snow, like winter had decided it was time to demonstrate a simpleton’s form of the Kutta-Joukowski theorum of aerodynamics for the otherwise uninitiated.
With the sky lit bright hard blue, closing in on white, you can see the plumes of light snow thrown straight upwards at the ends of frozen ponds — even though the wind that’s carrying the snow is running fast and parallel to the ground.
All of it explainable, all of it functional dynamics of wind speed and direction, of the weight and shape of snow.
The question is isolating it — look at a drift, and you can devise an explanation for its particular shape, even though the explanation might include a constant as transitory as the angle of repose for a
certain type and temperature of snowflake.
You could take one drift and find the mechanism that built it, everything from mid-term windshifts
on down through temperature changes and the fleeting effect of afternoon winter sun rounding the tips of ice crystals — heck, with enough money, you could build a room and make your own drift.
The problem is the micro and the macro.
The problem is that there is so much information, so many particulars, that making drifts and whiteouts is much more straightforwardly a question of experience — basing what will happen this time on what happened last time, rather than breaking down each single effect of each single potential change.
My yard is so small that it takes four sweeps of a pushmower to cut the grass, and I’m done in three minutes — and even that small postage stamp of yard has a hundred thousand variables, and that was without even taking account of the macro change of the neighbour’s fence blowing down.
Finding absolutes right now about something as big as climate change?
Tomorrow’s weather and today’s snowflake are already mystery enough.
Russell Wangersky is The Telegram’s
editorial page editor. He can be reached by email at firstname.lastname@example.org.