Drift Season

There’s a certain irony in the fact that winter, when I’m inclined to spend more time inside, may be the season when I’m most likely to be hyperaware of the weather. Presumably this is because snow affects our access more than does summer weather—although road closures in 2013 due to fires and flash flooding point toward the foolishness of making such blanket generalizations. It is nevertheless true that the synergy of snow and winter wind pose special challenges. Some years—and this is shaping up to be one of them—we end up shoveling or plowing the same snow multiple times as the wind re-arranges it again and again over weeks and even months.

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Parallel mini-drifts on Cap Rock Ridge in April, 2013.

As with many other aspects of life up on this high ridge in central Colorado, drifting snow gives me things to see and ponder. For example: snow quantity is not the sole variable that creates a drift worth noticing. This isn’t to say that having lots of snow on the ground is irrelevant—quantities of snow make for drifts that are not only deep but also broad. With six inches on the ground, we’ll often have enough room to skirt around a drift on the driveway with one of the cars if we need to. With twelve inches, we’re digging and plowing before we go anywhere. But smaller amounts of snow leave open the possibility that nuances of form that would be hidden in white-on-white with deep accumulations will be revealed as patterns of contrast and color in the wind’s aftermath. Working with just a few inches of snow, a strong north wind worked our area over with a daylong windstorm last spring. Where it crossed Cap Rock Ridge, the snow settled out into narrow drifts behind anchors as small as rocks, shrubs, and individual grass clumps. From here, white streaks laid over the tan grass made it look as if the slope had been methodically stroked by a gigantic comb.

And while it’s easy to finger snow and wind as the ringleaders in drifting events, they have collaborators. Contour is the most influential, of course—the ridges and edges and plants that channel and shape the flow of air across the land, dictating where it’s apt to accelerate and scrub the ground clean, and either slow down or vault over a high point, in both instances dropping its load. But contour has a spatial factor, and wind direction relative to landscape features means everything in the context of drifting snow. More often than not, the strongest winds blow out of the northwest or north this time of year. Under those circumstances, we know where drifts are likely to form, and we plan accordingly. Banks of snow that we deliberately plowed to what is normally the downwind side of the driveway, however, might create a perfect road-blocking heap when the wind swings around to blow out of the south.

Last week, three days of an atypical southwest wind created an impressive demonstration of another variable: temperature. Beyond the barn, ground blizzards slithered over a straightaway of driveway gravel. The days were clear and mild, and the sun created enough warmth to melt the snow as it passed over the dark ground, leaving an inch-thick, hundred-yard rink of transparent pebbled ice.

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Drift cross-section showing dust strata.

Last week’s wind event culminated with a shift to a more westerly flow and an overnight blow that thumped at the walls of the house, shrieking in the eaves and rattling the dryer vent. The wind carried a plume of grit off the road into the horse pasture, tinting the scant snow cover pink. Near the barn, the gale scoured the snow off a section of the riding arena, exposing the sand. When I plowed the drift that accumulated downwind of there, the cross section of the bank revealed alternating layers of white and tan, a chronicle of gusts.

That there are such weather-related novelties to encounter in this, our thirteenth winter in this place, is a reminder of how much remains to be seen, whether I’m looking out the window, venturing out into an inevitable tempest, or wandering around in the calm that just as inevitably follows.

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One Response to Drift Season

  1. edbrummel says:

    “…[It] is a reminder of how much remains to be seen, whether I’m looking out the window, venturing out into an inevitable tempest, or wandering around in the calm that just an inevitably follows.” Indeed. And not solely where only weather and snow are concerned. I find it funny that since this sort of looking and engaging is so at the core of your writing, that you feel you need any reminders. :~)

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