DISCOVERING WINTER / THE WORK OF ICE
Through thick and thin: keeping your life on ice
By CHRISTINE JEFFERS
Shunpiking Magazine, Volume One, No. 10, December, 1996
Quick scroll on this page to...
o White ice and black ice
o Falling through ice; "the gasp reflex"
o What to do if you fall through
o Big vehicles
o Ice: A home remedy that really works
Will you be heading out on the ice this winter? When you're out on the ice for any reason, preparedness is your key to avoiding calamity -- and can also be your key to survival. Make it your business to learn two vital things: how to check ice conditions, and what to do in an emergency. In stark reality, death awaits ice travellers who do not mentally and physically prepare for the possibility of treading thin ice.
Some take to the lakes for the invigorating thrill of ice boating, or wait for the big freeze at their cottage so they can hike or drive there directly across the ice. Some few even race their cars or all-terrain vehicles out on the lakes. And we all recognize outdoor skating as one of winter's most popular sports. While these pleasures can enliven your leisure time and put roses on your loved ones' cheeks. The conditions of an ice sheet can vary from morning to evening, day to day, and from one location to another on the same body of water.
Most of us would recognize unsafe ice conditions where water flows more quickly -- in a narrows or at the inlet or outlet of a lake, for instance -- this is where we often find "frazil" ice -- ice in its weakest form. But variations in density, thickness, and strength can occur anywhere, anytime. It's vital to be aware of this because appearances can be deceiving. Even when you return time and again to the same, familiar lake or river, don't mistakenly assume that since the ice was thick and solid last weekend, it'll be just as strong this weekend. Fluctuations in wind, temperature, precipitation and water can alter ice dramatically.
White ice and black ice
It doesn't seem to be commonly known that lakes, ponds and rivers can develop two distinct kinds of ice: White ice and black ice. This black ice is not to be confused with the treacherous black ice we meet on winter highways; in fact, for safety on any frozen body of water, the more black ice, the better.
The initial freezing of a lake's surface results in a cover of white ice. Once the lake has a solid surface, it conducts heat (from lower, warmer strata of water) upward through the ice into the cold air above. This loss of heat causes the ice sheet to thicken downward. The result is black ice, so-called because it appears black when you look down into the water at it. (Held up to the light, it would actually look blue.) Black ice is the strongest form of ice, because of its density; it forms beneath the surface, and contains very few air bubbles. By contrast, surface white ice has many air bubbles and tends to be granular; this gives it only about half the strength of black ice.
Beware: although they may look like they're safe, some ice covers are not reliable; they may be composed almost entirely of white ice. When heavy snowfalls occur early in the season, black ice may not become well-established below the white ice sheet. Snow acts as an insulator against heat loss from the lake. The snows' weight on the ice surface depresses it, drawing water up through cracks and forming slush, which then freezes into an additional thickness of white ice. (These conditions will also occur when there is a wind-whipped freeze-over during blizzards and snow storms.) Any surface-formed ice, in and of itself, should be considered unsafe for weight-bearing.
It's always wise to measure the thickness of ice before you go out on it. You'll need to measure the thickness of both white and black ice. One good tool for making a hole is an ice auger, found in some hardware stores. Remember: white ice is approximately half as strong as black ice. The total equivalent in black ice is the only figure on which to base your assessment.
You'll get this figure by adding half of the thickness of the white ice to the full thickness of the black ice. For optimum safety, a thickness of 15 cm (six inches) is best for walking and skating; 36 cm (14 inches) for a slow-moving snowmobile; 66 cm (twenty-six inches) for a larger vehicle like a car or a camper.
Falling through ice; "the gasp reflex"
If there is anyway to convince you to go out on the ice more prepared, reading the following sequence may be all you need.
In a fall through ice, survival odds are not great. Hold this thought! Yet, survival is possible. (Hold that thought!) Have you ever taken the time to imagine just what you would do if you fell through the ice? The thought is too harrowing -- finding yourself in a life or death drama demanding almost unrealistic clear-headedness.
Any one who has ever jumped or fallen into very cold water may recall experiencing a drastic, involuntary intake of breath. This is called "the gasp reflex". With it comes breathlessness and an increase in the rate of breathing, the latter accompanied by a powerful urge to inhale. Simultaneously, your ability to hold your breath just dropped from a minimum 60-second capacity to a desperate 7-15 seconds. Consider these elements coming into play at the moment the ice gives way; understand that you do not want this to happen to you or anyone you care about.
If you fall through ice, knowing what happens during the gasp reflex might help you challenge panic during the first crucial moments. While your body plunges downwards, it is imperative to fight the urge to inhale and wait for your downward momentum to be replaced by your natural buoyancy. Of course, the winter gear you're wearing will counteract the upward motion. And all the while, you must strive to stay oriented, praying that you will locate the opening your body just made in the ice.
Return, if possible, to the site of entry... aware that the ice here was at least strong enough to support you a minute ago. You'll be thrashing around, but your body is losing heat rapidly and it's essential to conserve movement. Get hands and arms out onto the unbroken ice. If it cracks, propel forward to a solid surface, keeping arms out. Try to bring your body level with the ice; if you can gain purchase on it with a foot or a knee, you may have a fighting chance. Once on the ice, roll. Don't stand upright until you are positive the ice will hold you.
When attempting a rescue, if you cannot reach the victim from a stable area, lie flat across the ice and extend the longest item you can find -- a scarf, ladder, rope, even a jacket -- for him to grasp. Act quickly. His ability to hold on, both mental and physical, will be increasingly impaired by the onset of hypothermia.
- Chris Jeffers
What to do if you fall through
o Stay calm to conserve energy; try to think clearly
o Don't try to take off your winter clothing. It may provide some buoyancy and help keep you warm.
o If you're walking on the ice and fall through, try to return to where you fell in. The ice near there is more likely to be able to support you.
o Ice near open water is very slippery and hard to grasp. To get out of the water, kick as hard as possible to push yourself up and on to the ice.
o Get hands and arms out on to the unbroken ice. If it cracks, propel forward to a solid surface, keeping arms out. Try to bring your body level with the ice; if you can gain purchase on it with a foot or a knee, you may have a fighting chance. Once on the ice, roll. Don't stand upright.
o Dig in claws or grabbers at an arm's length in front of you and pull yourself slowly forward. Repeat until you reach firm ice.
There are things we can all do to make our forays onto natural ice safer; accordingly, they'll be good memories to recall next July as we press icy glasses of lemonade to our brows. Before hitting the ice, exercise these safeguards:
o Check the local forecast on the day of your excursion.
o Measure the ice.
o When visiting a new area, heed information from local folk who are familiar with its ice cover and climate.
o Always practice the "buddy" system.
o Tell people where you are going and when you expect to be back.
o Avoid ice travel during darkness. Setting out in daylight? Time your return accordingly.
o When walking on ice, carry a long pole as a walking stick. It can be used to test uncertain areas and to straddle a hole if you fall through.
o Carry ice picks, good for gaining a grip on ice in emergency situations. These can usually be found at hardware stores: "claw" style picks, which can be slung around your neck, are recommended.
o Carry a long rope.
o Carry an emergency kit with flares, waterproof matches, flashlight, and first aid supplies.
o If you're snowmobiling, carry spare parts and essential tools; it's also a good idea to wear reflective tape on your helmet.(You are wearing a helmet, aren't you?)
o Never assume that the ice on a snowmobile track is safe to walk or drive on. The latest snow machines can skim very quickly across ice which may in fact be too unstable to support the weight of someone walking or a slower-moving machine.
There is truly no safe condition for driving larger vehicles on ice. If you insist, be aware of these facts:
o Ice should be at least a uniform 66 cm (26 inches) thick.
o Drive with the window open to ensure escape from the vehicle if it becomes submerged.
o If parking on ice, bear in mind that ice will fatigue under a car's weight; park in a different spot each time and don't park vehicles together.
o Slow down as you approach a shoreline. The car's motion causes the ice sheet to sag, sending a pressure wave to the bottom of the lake. It rebounds off the bottom, magnifying as it spreads towards shore. This can actually crack the ice. Even a smaller vehicle like a snowmobile can cause this. Sometimes a wave returning from shore will meet one heading to shore -- this can cause cracking offshore; for this reason, it is safest to approach shore from an angle at a very slow speed.
You may have lived your whole life until now sporting with friends and family -- or even alone -- on frozen lakes, rivers and ponds without mishap.
But if you were uncertain how thick safe ice should be or didn't test it, and if you weren't aware of these precautions and emergency procedures, you've been very lucky.
Think about it -- before you once again put your life on ice.-CJ
Ice: A home remedy that really works
In the days before so many over the counter drugs became available, people used to treat all sorts of minor ailments with whatever they had around the house. Most minor physical problems don't require a trip to the doctor -- or even a trip to the neighbourhood pharmacy -- but can be treated or prevented with a little home care.
Ice can be helpful in treating a variety of afflictions, such as bruises, black eyes, nosebleeds, bee stings, and poison ivy:
o Applying an ice pack to an injury immediately after it occurs can sometimes prevent unsightly bruises from developing. Doctors suggest applying ice packs at 15 minute intervals, allowing time in between for the skin to warm up again. (Cooling will constrict blood vessels, allowing less blood to spill into the surrounding tissue and cause black splotches.)
o Putting an ice pack on your forehead or the back of your neck in the early stages of a headache not only soothes the pain; it can freeze it in its tracks.
o Years ago, people put leeches on black eyes, but nowadays most people would probably prefer to use ice packs (although bags of frozen vegetables also suffice). The cold keeps the swelling down and also constricts blood vessels, leading to less of the internal bleeding that causes the black and blue colour. Doctors recommend crushing ice, putting it in a plastic bag, and applying it for ten minutes every two hours for the first one to two days after an injury.
o Because cold constricts blood vessels, ice packs are an excellent way to reduce bleeding from a bloody nose.
o An ice pack -- or even just an ice cube -- placed on a bee sting can ease the pain, reduce the swelling, and keep bee venom from spreading. Ice can numb the itch if you have contracted poison ivy.
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