Published April 1, 2000 12:00AM
I should have known better. A thousand feet above the nearest tree was not the place to pitch a tent named “Timberline.” I had waited out many a northern storm inside this tent, crammed in way too many card-game compatriots, even proposed to my wife inside. But my old warhorse was no match for the unbridled wind that blasted my campsite on Canada’s Caribou Mountain. First the door popped. Then the poles snapped. After several hours of lying there, the collapsed roof flapping crazily in my face, I felt sure my sanity would be the next thing to go.
“People underestimate the wind,” says naturalist Jan DeBlieu, author of Wind: How The Flow Of Air Has Shaped Life, Myth And The Land. “Its swings of mood are devilishly tricky to foretell.” True enough, yet there are some facets of wind that we can rely on with certainty. For instance, it’s safe to assume the kind of mountain winds I encountered above treeline in the Yukon Territory will, indeed, rip a decrepit old three-season tent to shreds.
We also know that wind is a complex element of nature, a collection of forces that have one simple origin: the sun. Where the sun shines longest and strongest, the ground is warmed, air rises above it, and cooler air flows in to fill the vacuum. In other words, wind is essentially the flow of air from cool regions to warmer ones. Expand that concept to global proportions, and you’d probably think that warm air at the equator rises, the equator sucks cold air from the poles, and thus, that all air flows north or south. Not quite. Like I said, wind is a complex force of nature.
The Earth’s winds stem from a complicated interaction of the planet’s rotation and the constant heating and cooling–and, therefore, rising and falling–of air at every latitude. The net effect for North America is surface winds that flow reliably from west to east, with influxes of cooler Arctic air mixed in and creating more volatile weather fronts to keep things interesting.
Finally, there are the effects the Earth’s surface has on wind. Example: Air heats more quickly over land than water, as well as over certain types of land, such as deserts. Uneven heating, combined with the disruptive effects of changing topography, create a jumble of airborne eddies that often defy understanding.
READING THE WIND
With so many seemingly whimsical forces involved, what’s a wind-battered hiker to do? Don’t despair. There’s enough method to this breezy madness that you can develop some coping strategies. Consider my wind-watching grandmother, who favored a little phrase backpackers would do well to remember: “West wind, best wind,” she said, and she was usually right. For many parts of the northern hemisphere, winds that blow from the west bode well for stable weather patterns. The flip side is that easterly winds, often caused by the counterclockwise spin of a low-pressure system, usually bring instability and some kind of precipitation. It’s for good reason that weather-wise New Englanders declare, “When the wind is blowing in the East, ‘Tis not fit for man nor beast.”
Likewise, sudden swings in wind intensity or direction almost always bring a change in the weather. So here’s another one to pack in your mental gear: “A backing wind means storms are nigh; a veering wind will clear the sky.” Translation? Think of a compass. Veering refers to a clockwise wind shift, say from north to east, which often brings fair weather. A backing wind shift goes backward, or counterclockwise, from north to west. Bad weather won’t be far behind. In unfamiliar terrain, your compass will serve you well not only for navigation, but also for reading the wind and weather.
HIGH FLYING WINDS
This is something probably every hiker has figured out: Wind speed increases with elevation. But what you may not realize is the impact it has on your body. “Even a small increase in wind speed can dramatically increase wind stress on you,” says DeBlieu. “A doubling of wind speed from 10 to 20 miles per hour quadruples the stress–or force–on your body.”
If the wind is really howling, hunch over or crawl if you must. Not only will your center of gravity be lower and more stable, you’ll also be traveling in less forceful wind at ground level. Plus you’ll be giving the wind less surface area to slam into, which is why low-profile tents are generally more wind-worthy than those with steep sides and a high profile.
If you’re planning on hiking or making camp up high, remember that the average wind speed in the mountains is always greater than down below. And if you’re going above treeline, the lack of windbreaks makes for an even more dramatic difference. So pack in wind-shedding clothing like a rain jacket and pants, or a lightweight nylon pullover and wind pants, even if it’s dead calm at the trailhead down low.
The RIGHT SITE
As I learned so graphically that night on Caribou Mountain, where you pitch your tent is critical in wind-whipped elevations. That’s why I consulted Erik Frebold, a tent buyer/designer with Vancouver-based Mountain Equipment Co-op who likes to bolt tents to truck beds, then fly down abandoned airplane runways at 80 miles per hour. The exercise “creates some educational collapses,” Frebold says, so I figured he’d be full of advice on how to avoid in-the-field collapses, too.
Ideally, you want to align your tent with its long axis parallel to the anticipated wind direction (i.e. into the wind). Then stake it down as tightly as possible, using all available guyline attachments. It’s a good idea to tuck a few extra feet of line in your pack, in case you discover a flapping area that needs some battening down.
If you must camp in an exposed area, use the local vegetation as a clue to wind direction. Shrubs or trees usually have the fewest branches and baldest-looking bark on the windward side, since ice rime and sharp windblown ice crystals accumulate there, damaging both bark and branches. In such situations, conifers like spruce and fir often look strikingly “flagged,” with nothing but clumps of needles hanging off one side and not much else below–except a naked trunk. Elongated patterns in snow or sand are other good clues to prevailing winds. “Those nice, scooped out spaces didn’t get there by accident,” says Frebold.
FAVORABLE WINDS
Wind does have its positive side. It has a debilitating effect on both the coordination and appetite of most biting insects. In fact, the stronger the wind, the better (for us, that is.) Ten miles per hour seems to be the magic threshold at which flying insects are kept at bay. The rule, in short, is to take the high trail or windward shore to lessen your loss of blood. When looking for a campsite, avoid the wet, still woods and find a high, breezy outcrop or open shoreline.
In bear country, the wind is a double-edged sword that can both attract and repel bruins. Bears have an incredible sense of smell, and a good breeze can carry food odors many miles. To prevent unwanted encounters, cook downwind of your campsite and keep your cooking time to a minimum. After cooking and eating, immediately wash all utensils, as well as your face and hands, and bag all food scraps.
On the other hand, most bears are repelled by human scent. Whenever you can, try to keep the wind at your back. This puts your scent ahead of you, warning bears that you’re coming so they can move out of the way.
Last, if a bear is threatening you, be sure the wind is at your back before firing pepper spray. This may sound obvious, but rational thought can escape you when confronted by bear. Going temporarily blind from a self-inflicted dose of pepper spray will probably lower your odds of survival. If possible, take a half second to check the wind and maneuver accordingly before you spray.