The Children's Blizzard

by David Laskin

  Nearly half of their bodies’ total heat production radiated through their uncovered heads in the form of infrared energy—invisible wavelengths of electromagnetic energy that travel through the air until they are absorbed by an object in their path. Radiational cooling, as the process is called, is what created the frigid air mass of the cold wave in the first place: During the run of calm, clear nights up in Canada earlier in the month, temperatures dropped quickly at the surface of the earth as the long waves of infrared energy radiated into the atmosphere. With no clouds to reflect the long waves back, they just kept rising and radiating heat up and out into space. On a much smaller scale, the same thing was happening to the body heat rising off the boys’ heads.

  Their wet clothing sapped away additional body warmth through evaporation and conduction. In order to evaporate—in other words, to change state from liquid to gas—water must absorb heat. Sweat cools the body by whisking away warmth as it evaporates off the skin. The water in the boys’ wet clothing acted the same way as sweat does, and the wind greatly exacerbated the heat lost to evaporation. What made it worse was that their clothing never dried because the wind kept plastering them with snow, which the warmth of their skin melted. The wet absorbent material of their shirts and trousers and underwear soaked up even more heat.

  Conduction, the process that moves heat directly from one object to another, wicked heat from the surface of the boys’ skin to the cold water that saturated their clothing. Since heat is conducted twenty-five times faster in water than in air, the most mortally efficient conduction occurs when a person falls into cold water. Even water at 60 degrees is cold enough to quickly induce a condition known as immersion hypothermia. The boys carried their own frigid streams of water around their bodies. Later, when they knelt to pray, more heat would be conducted from their legs into the snow.

  Most insidious was convection, the process that carried off the small envelope of heated air next to their skin. Convection, the transfer of heat by the movement of the air itself, accounts for why hot soup cools faster if we blow on it: Our breath carries off the hot, steamy air rising off the surface of the soup and replaces it with cooler air; as the soup transfers its heat into the flow of our breath, it cools. In the blizzard, the incessant wind was the breath that stripped away the warmth of the boys’ bodies and mixed it into the colder air around them. For a time their bodies kept producing more heat, and the wind kept blowing it away and replacing it with cold air. But eventually they started losing heat faster than their bodies could make it. Again, there is an analogy with water: An icy current would have acted in the same way had the boys fallen into a river. In a sense they were being swept along in a river of air—and the swifter the current, the faster the thin shells of their body heat were peeled from them.

  An American explorer and scientist named Paul Siple worked out a formula for how convection kills through a combination of cold and kinetics. He called it the windchill factor. Cold, of course, can kill without wind, but it takes longer. Wind and cold together accelerate the process. To be precise, the amount of body heat lost to wind increases as the square of the wind’s velocity. Air moving at 8 miles an hour saps the body of four times more heat than air moving at 4 miles an hour; at winds of 20 miles an hour, twenty-five times more body heat is lost than at 4 miles an hour. Paul Siple had a lot of experience with wind and cold because he spent years working as the biologist on the Antarctic expeditions of Admiral Richard E. Byrd during the 1930s and ’40s. It was in the Antarctic that he calibrated windchill through a series of experiments with water in plastic cylinders. Siple’s windchill index has since been revised, updated, and recalibrated, most recently by the National Weather Service in 2001, but the fundamentals remain.

  Television weathercasters like to say that windchill is what the weather feels like. Using the 2001 windchill index, when the wind is blowing 30 miles an hour at a temperature of 25 degrees, it feels like 8 degrees. “Feels like” is a fuzzy term for an exact transaction. What windchill means is that it’s irrelevant that the thermometer reads 25 degrees: If the wind is blowing at 30 miles an hour, the exposed parts of your body are losing heat at the rate that they would if the temperature were in fact 8 degrees.

  When the Schweizer boys left school late in the morning, the windchill was about 5 degrees above zero. At 9 P.M., four hours after the sun set, the windchill had dropped to 40 below zero. In conditions like that, exposed human flesh freezes in ten minutes.

  Ten minutes to turn warm skin and blood to ice. The five boys had been outdoors by that point for over nine hours.

  For a while, shivering kept them warm. The twitching started in their faces and necks and moved down their torsos and out to their arms and legs, rhythmic waves that rippled through their muscles at a frequency of six to twelve cycles every second. As long as their flesh jumped and danced around their bones, their muscles were producing enough heat to keep their bodies warm. Inside, their vital organs went on working normally. But shivering cost them dearly. As they shivered, their consumption of oxygen doubled or tripled, a sign of accelerating metabolism. Heinrich and Elias quickly burned through the calories of their last meal—the coarse bread sweetened by syrup or jam they had carried with them to school that morning. When that was gone their bodies looked for more fuel with which to combat the cold. But there wasn’t any—at least nothing they could convert to heat quickly. The boys had expected to be home by now, with a fire and a smiling mother to cook their supper, so they had brought no food but their meager lunches.

  Shivering on an empty stomach is like burning your clothes in the stove once the coal and furniture are ash. The energy it took to walk, just to remain upright in the wind, made their body heat dissipate even faster. Fear threw open still more vents. Even mild mental stress hastens heat loss. Terror and exhaustion are as efficient as wind in scouring heat out of the human body.

  The Schweizer pioneers frowned on complaining. Their children were raised to be cooperative, to think of others before themselves, to work together for the good of the family and the group—above all, to be humble before God. So it came as a shock to the older boys when Heinrich and Elias started falling behind and whining. They were hungry. They couldn’t feel their feet or hands. Their eyes stung from the blowing snow.

  Johann heard his younger brothers wail over the shriek of the wind and could hardly believe his ears. Crying like babies, screaming for the others to wait for them. Johann saw Elias fall as he stomped through the drifts trying to catch up. Or perhaps Heinrich had pushed him. Then Heinrich stumbled. Both of them were angry and red-eyed. The bickering and crying were signs that the younger boys’ bodies were beginning to succumb to the cold.

  Irritated as he was, Johann would never have dreamed of abandoning his brothers. The five of them must stay together no matter what. Johann motioned to Peter Graber and Johann Albrecht to stop. The three older boys put their faces together so they could hear each other and talked about what to do. Peter Graber and Johann Kaufmann, the two sixteen-year-olds, took charge. They knew it was essential to keep moving and continue looking for shelter. If the little ones couldn’t go on they would carry them. Johann and Peter bent over at the waist and had the small boys climb onto their backs. Now there were three sets of tracks instead of five.

  For a time, the exertion did Johann and Peter some good. Or seemed to. The effort of carrying the extra weight sent a ripple of warmth through their bodies. And shivering contributed its own pittance of heat—for despite the exertion, it was so cold in the wind and their clothes were so thin that they still shivered. Shivering and labor combined to work and warm their muscles. But it was warmth they couldn’t afford for very long. The boys were paying for every step and every spasm—paying with precious currency. Without food, without relief from the wind and cold, they were soon bankrupted.

  Whenever they stopped moving even for a moment, to catch their breath or peer into the impenetrable air, the tide of warm blood ebbed from their skin and extr
emities and flowed inward to the centers of their bodies. But the tide was no longer warm enough to boost the temperature inside them. The heat of exertion rose off them and dissipated like steam. Gone. Their core temperatures, the temperature of the blood near their hearts, began to drop. At 95 degrees they exhibited the first signs of mild hypothermia.

  Strangely, their minds were affected before their bodies. The boys became peevish. They wanted to argue, but when they opened their mouths to shout over the wind, they had trouble forming the words. Thoughts came slowly and only with exaggerated effort, like moving under water. For the first time, they blamed each other for wandering off from Mr. Cotton and the two younger Graber boys. The three who were still walking stumbled, and they saw each other stumble, and for some reason this filled the boys with annoyance and disgust. Shivering reached a climax as their bodies clung to an internal temperature of 95 degrees, but the uncontrollable twitching of their flesh disgusted them as well.

  It is during this first mild stage of hypothermia that mountaineering and exploring parties start to bicker and group solidarity breaks down. Ordinarily docile and cooperative individuals turn waspish and vindictive; leaders make bad choices. Everybody thinks someone else is to blame for the misery of being out in the cold. Mountaineers call it “cold stupid.” The dulled mind begins to throb around a single image—really more a sensation than an image: the craving for warmth.

  Johann and Peter were now shivering so violently that it was difficult to hold Heinrich and Elias on their backs. What made it worse was that the younger boys had gone limp on them, like half-empty sacks of peas. Johann kept shouting for his younger brother to grab tightly to his shoulders, but the little boy made not the slightest effort. Again and again he slid to the ground. He just sat in the snow staring dazedly when his brother bent over to pick him up again. Johann could hardly restrain himself from smacking the child.

  What Johann did not realize was that Heinrich and Elias had become dangerously chilled while he and Peter were carrying them. Lying inert against the older boys’ backs, they had fallen into the apathy of deeper hypothermia.

  At outside temperatures of 35 below zero, the body loses a degree of heat every thirty to forty minutes—and far more rapidly than that if the clothing is wet. By evening the windchill temperature began to approach that level in Dakota. As their core temperatures dropped degree by degree, the boys’ minds betrayed them more severely and bizarrely. With their body temperatures at 93, amnesia began to cloud their thoughts and impair their judgment. Thoughts oozed slowly out of their brains, and time itself seemed to drag on leaden feet. This is the temperature at which people make foolish, sometimes fatally foolish, decisions. They take the wrong path. They refuse to turn back from their attempt to reach the mountaintop. They lose gloves or hats or discard precious supplies. It’s like being insanely drunk with cold. From here on, the boys would remember nothing.

  When their internal temperatures hit 91 degrees, they ceased to care what happened to them. Their speech became slurred. Johann Kaufmann and Peter Graber and Johann Albrecht were now as dull and apathetic as the limp younger boys cradled in their arms. Their bodies were so cold that nerve impulses moved sluggishly to muscles, and the muscles failed to respond normally once the impulses reached them. The boys stared down at the frozen blocks of their hands and wondered dimly why they couldn’t make them move or feel anything. They had trouble contracting the muscles in their thighs and calves that they needed in order to walk; but once the muscles contracted, they couldn’t relax them again. The boys stumbled and staggered. It was the wind that determined where they went, not their numbed brains.

  As darkness fell, Maria and Johann Albrecht took some small comfort in the fact that the teacher, Mr. Cotton, hadn’t come back either. They had gone over it again and again through the long day of waiting and wondering. Mr. Cotton, who was boarding with them, must have stayed at the schoolhouse with their son Johann and the other children. That would explain why neither he nor the boy had come home. Albrecht reassured his wife that this was the only possibility. He had been outside himself when the storm hit and he knew how bad it was. Albrecht had never seen anything like this in all their years in Dakota. It would have been madness for the teacher to dismiss school and send the children out into this storm.

  Maria Albrecht tried to believe her husband. She agreed that they must not even think of traveling to the school to get Johann until the wind had died down. Now in the darkness the storm was more dangerous than ever. Together they would pray and wait for the morning. But still, whenever she saw Johann’s younger brother Peter, Maria could not stop herself from sighing and shaking her head. “O where is my child?” she wailed. “My heart is going to break.”

  Shivering is a very demanding way of warming the body. But the body shivers as long as it’s able to because the alternative is much worse. Shivering is the body’s last defense against the abyss of deep, potentially fatal hypothermia. Once shivering stops, the chilled body falls quiet and then shuts down rapidly. On a graph of temperature loss plotted against time, the drop from 98.6 to 90 looks like an intermediate ski slope; below 90 is a cliff.

  Heinrich and Elias stopped shivering first; then Johann Albrecht; finally Johann Kaufmann and Peter Graber. Their core temperatures were now around 88 degrees. Severe hypothermia had set in.

  The functions of their vital organs slowed. The chilled blood thickened. Their hearts turned stiff and frail as the cold penetrated deeper. Like the muscles of their legs and arms, their heart muscles failed to respond efficiently to nerve impulses. Contractions became weaker and weaker; the pumping action was barely forceful enough to push the viscous blood through their veins. A vicious cycle set up as their weakened hearts failed to supply the tissues with the oxygen they were craving: The lack of oxygen made their bodies unable to complete the metabolic cycle, causing lactic and pyruvic acids to accumulate in their tissues; the buildup of these acids made their hearts beat even more feebly and erratically, which in turn spiked levels of the acids.

  The deepening cold radically redistributed their bodily fluids. During the first hours, the blood had retreated from their skin and extremities into the core of their bodies to keep the central organs warm. The temporary rise in the volume of blood flowing through vessels deep inside increased the production of urine. Soon the boys were desperate to urinate, but their hands were so paralyzed by cold that they couldn’t open their flies. Eventually, as their bladders emptied repeatedly and their core temperatures kept falling, their blood volume began to decrease. The blood itself became increasingly viscous as more and more water was retained in their tissues. Their kidneys were no longer able to conserve water. The boys urinated again and again, probably wetting themselves and adding to their misery. Dehydration became acute, and this in turn made their blood volume sink even lower.

  There was a measure of protection in this shutting down of their internal processes, at least for a time. As their metabolism slowed, their brains required less oxygen, which was fortunate since their bodies were incapable of supplying much. Doctors today routinely induce extreme hypothermia during certain open-heart operations by pumping very cold blood into the body with a heart-lung machine. For an hour or so, the doctors keep the body at the threshold of death while they operate on the cold, motionless heart. The stilled pulse and the barely functioning brain reduce the patients’ risk of heart attack or brain damage. Had the boys been rescued at this point and warmed properly, they might have recovered fully from an internal temperature of 88. It’s dangerous to be this cold but not necessarily fatal.

  But the odds of being rescued diminished steadily as the day wore on. The Kaufmanns and the Albrechts still believed that their sons had stayed in school, as they had been told to do again and again. And the Graber parents, who knew the truth, were too frightened to go out searching in the storm.

  At 87 degrees, the boys probably would not have recognized their parents anyway.

  Below 87 degrees, th
ey began to lose their grip on reality. They ceased to know or care that they were cold. They gave up looking for shelter.

  Hallucinations and delusions set in. Starved of oxygen, unhinged by stress and fatigue, the brain fabricates its own reality—often the fulfillment of desperate prayers. Two hikers stranded on Everest at 28,600 feet in temperatures of –35C hallucinated together that their supply officer had joined them in their bivouac—the only person in the team who might have brought them dry sleeping bags, food, and oxygen. Sailors who survived the sinking of the USS Indianapolis in the eastern Pacific in July 1945 hallucinated that an island was within reach. Some of the men stripped off their life jackets and drowned. The Hans Christian Andersen fairy tale “The Little Match Girl” is a classic case of wish fulfillment hallucinations induced by severe hypothermia: a small girl, shivering barefoot in her snow-dampened rags, watches in amazement as a series of fantastic images appears out of thin air every time she strikes a match—a warm stove, a table laden with food, a Christmas tree glittering with candles, the return from the grave of her recently deceased grandmother. The next morning, passersby find the girl dead, with a smile on her face.

  Johann, Heinrich, and Elias Kaufmann, Peter Graber, and Johann Albrecht, brought up together in the tight-knit, deeply religious world of the Ukrainian Mennonites, may have hallucinated that Jesus came down in his flowing robes to take them to heaven. Or that their mothers walked out of the storm bearing plates of hot poppy seed cake or the savory dish they called Käseknöpfle—literally, cheese buttons—made of delicious dough and cheese and onions.