Drawing on his experience of living in Anchorage, Alaska, biologist Bill Streever takes the reader on a celebratory tour of the science, history, geography and ecology of cold temperatures.
The world warms, awash in greenhouse gases, but forty below remains forty below. Thirty degrees with sleet blowing sideways is still thirty degrees with sleet blowing sideways. Cold is a part of day-to-day life, but we often isolate ourselves from it, hiding in overheated houses and retreating to overheated climates, all without understanding what we so eagerly avoid.
We fail to see cold for what it is: the absence of heat, the slowing of molecular motion, a sensation, a perception, a driving force. Cold freezes the nostrils and assaults the lungs. Its presence shapes landscapes. It sculpts forests and herds animals along migration routes or forces them to dig in for the winter or evolve fur and heat-conserving networks of veins. It changes soils. It preserves food. It carries with it a history of polar exploration, but also a history of farming and fishing and the invention of the bicycle and the creation of Mary Shelley's Frankenstein. It preserves the faithful in vats of liquid nitrogen from which they hope one day to be resurrected.
Imagine July water temperatures of thirty-five degrees. Imagine Frederic Tudor of Boston shipping ice from Walden Pond to India on sailing ships in 1833. Imagine Apsley Cherry-Garrard on his search for penguin eggs at seventy below zero in 1911. Imagine a dahurian larch forest that looks like a stand of Christmas trees on Russia's Taymyr Peninsula at sixty below or a ground squirrel hibernating until its blood starts to freeze and then shivering itself back to life.
But none of this is imaginary. Our world warms, but cold remains. In the ordinary passing of a calendar year, the world of cold emerges. For someone with Raynaud's disease, a September stroll temporarily changes cold hands into useless claws. Caterpillars freeze solid in October and crawl away in April. Average temperatures in certain towns drop to twenty below zero in January.
It is time to enjoy an occasional shiver as we worry about a newly emerging climate likely to melt our ice caps, devour our glaciers, and force us into air-conditioned rooms. It is time to embrace and understand the natural and human history of cold. Even in a warming world, a world choked by carbon dioxide and methane, cold persists, biting my lungs and at the same time leaving me invigorated, alive and well on an Arctic spring afternoon with the sun hovering low over an ice-covered horizon and the thermometer at forty below.
It is July first and fifty-one degrees above zero. I stand poised on a gravel beach at the western edge of Prudhoe Bay, three hundred miles north of the Arctic Circle, and a mile of silt-laden water separates me from what is left of the ice. The Inupiat -- the Eskimos -- call it aunniq, rotten ice, sea ice broken into unconsolidated chunks of varying heights and widths, like a poorly made frozen jigsaw puzzle. A few days ago, the entire bay stood frozen. During winter, it is locked under six feet of ice. Trucks drive on it to resupply an offshore oil production facility. If one were insane, or if one were simply too cheap to fly, or if boredom instilled a spirit of adventure, one could walk north to the North Pole and then south to Norway or Finland or Russia. Temperatures would range below minus fifty degrees, not counting windchill.
But even in summer, the weather resides well south of balmy. A chill gust runs through me as I stand shirtless on the water's edge, wearing nothing but swimming shorts in the wind and rain. "The only way to do this," I tell my companion, "is with a single plunge. No hesitation." I go in headfirst. The water temperature is thirty-five degrees. I come up gasping. I stand on a sandy bottom, immersed to my neck. The water stings, as if I am rolling naked through a field of nettles. I wait for the gasp reflex to subside. My skin tightens around my body. My brain -- part of it that I cannot control -- has sent word to the capillaries in my extremities. "Clamp down," my brain has commanded, "and conserve heat." I feel as if I am being shrink-wrapped, like a slab of salmon just before it is tossed into the Deep Freeze.
My companion, standing on the beach, tells me that I have been in the water for one minute. My toes are now numb.
Time passes slowly in water of this temperature. I think of the ground, permanently frozen in this region to a depth of eighteen hundred feet. I think about hypothermia, about death and near death from cold. I think of overwintering animals. I think of frozen machinery with oil as thick as tar and steel turned brittle by cold. I think of the magic of absolute zero, when molecular motion stops.
After two minutes, I can talk in a more or less normal tone. But there is little to discuss. There is, just now, almost no common ground between me and my companion, standing on the beach. I feel more akin to the German soldiers whose troop carrier foundered, dumping them into Norwegian coastal waters in 1940. Seventy-nine men did what they could to stay afloat in thirty-five-degree water. All were pulled alive from the water, but the ones who stripped off their clothes to swim perished on the rescue boat. Suffering more from hypothermia than those who had the sense to stay clothed, they succumbed to what has been called "afterdrop" and "rewarming shock." Out of the water, they reportedly felt well and were quite able to discuss their experience. But as the cold blood from their extremities found its way to their hearts, one after another they stopped talking, relaxed in their bunks, and died.
"Three minutes," my companion tells me.
I am a victim of physics. My body temperature is moving toward a state of equilibrium with this water, yielding to the second law of thermodynamics. I shiver.
Several hundred miles southwest of here, six days before Christmas in 1741, the Dutch navigator Vitus Bering, employed by Russia, lay down in the sand and died of scurvy and exposure, while his men, also immobilized by scurvy, cold, and fear, became food for arctic foxes. Some accounts hold that Bering spent his last moments listening to the screams and moans of his dying men. The Bering Sea, separating Russia and Alaska, was named for him, and the island where he died, nestled on the international date line, is known today as Bering Island.
Northeast of here, in 1883, Adolphus Greely led twenty-five Ve men to the Arctic, stopping at Ellesmere Island. For most of them, the trip was a slow death that combined starvation, frostbite, and hypothermia. Greely himself, with five others, survived. He eventually took charge of what would become the National Weather Service, where he failed to predict a blizzard in which several hundred people died from frostbite and hypothermia. Many of the dead were schoolchildren.
Half a century after Greely's expedition, in the 1930s, the missionary ascetic Father Henry lived at Pelly Bay, in Canada's Northwest Territories, well above the Arctic Circle. By choice, he resided in an ice cellar. Indoor temperatures were well below zero. The natives would not live in an ice cellar, which was designed to keep game frozen through the short Arctic summer. It was the antithesis of a shelter, analogous to living in a shower stall to avoid the rain. Father Henry believed that it focused his mind on higher matters. Almost certainly, some of the natives believed that Father Henry was mad.
"Four minutes," my companion calls. The stinging in the skin of my thighs has turned to a burning pain. Frostbite is not a real possibility at this temperature, and true hypothermia is at least ten minutes in the future. What I feel is no more than the discomfort of cold.
Frogs are not found this far north, but at their northernmost limit, five hundred miles from here, they overwinter in a frozen state, amphibian Popsicles in the mud. Frogsicles. But caterpillars are found near here. I sometimes see them crawling across the tundra, feeding on low-growing plants. They freeze solid in winter, then thaw out in spring to resume foraging between clumps of snow. They are especially fond of the diminutive willows that grow in the Arctic.
Ground squirrels overwinter underground. They are related to gray and red squirrels and to chipmunks, but in appearance they are more similar to prairie dogs. In their winter tunnels, their body temperature drops to the freezing point, but they periodically break free from the torpor of hibernation, shivering for the better part of a day to warm themselves. And then they drift off again into the cold grasp of hibernation. Through winter, they cycle back and forth -- chill and shiver, chill and shiver, chill and shiver -- surviving.
Arctic soil behaves strangely around the hibernating ground squirrels. Underground, liquid water is sucked toward frozen water, forming lenses of almost pure ice. The soil expands and contracts with changing temperatures, forming geometric shapes, spitting out stones on the surface, cracking building foundations. Wooden piles cut off at ground level are heaved upward by ground ice, sadly mimicking a forest in this frozen treeless plain.
This water I stand in feels frigid, bitingly cold, but in the greater scheme of things it is not so cold. A block of dry ice -- frozen carbon dioxide -- has a surface temperature just warmer than minus 110 degrees. James Bedford has been stored in liquid nitrogen at minus 346 degrees since 1967, awaiting a cure for cancer. The surface of Pluto stands brisk at minus 369 degrees. Absolute zero is some five hundred degrees colder than the water that surrounds me.
"Five minutes," my companion tells me. I leave the water, shivering, my muscles tense. It will be two hours before I feel warm again.
* * *
There is more than one way to measure temperature. Daniel Fahrenheit, a German working in Amsterdam as a glassblower in the early 1700s, developed the mercury thermometer and the temperature scale still familiar to Americans. He built on work dating back to just after the time of Christ and modi?Ed by the likes of Galileo, who used wine instead of mercury, and Robert Hooke, appointed curator of the Royal Society in 1661, who developed a standard scale that was used for almost a century. In 1724, Fahrenheit described the calibration of his thermometer, with zero set at the coldest temperature he could achieve in his shop with a mixture of ice, salt, and water, and 96 set by sticking the instrument in his mouth to, in his words, "acquire the heat of a healthy man." He found that water boiled at 212 degrees. With only a minor adjustment to his scale, he declared that water froze at 32 degrees, leaving 180 degrees in between, a half circle, reasonable at a time when nature was believed by some to possess aesthetic symmetry.
Anders Celsius, working in Sweden, came up with the Celsius scale in 1742. Conveniently, it put freezing water at zero and boiling water at one hundred degrees. Less conveniently, it set in place a competition between two scales. An Australian talking to an American has to convert from Celsius to Fahrenheit, or the American will think of Australia as too cold for kangaroos. An American talking to an Australian has to convert from Fahrenheit to Celsius, or the Australian will think of America as too hot for anything but drinking beer. The Australian is forced to multiply by two and add thirty-two, or the American is forced to subtract thirty-two and divide by two. Or, as more often happens, they drop the matter of temperature altogether.
Lord Kelvin realized in 1848 that both Fahrenheit and Celsius had set their zero points way too high. He understood that heat could be entirely absent. At least conceptually, absolute zero was a possibility. He came up with his own scale, based on degrees Celsius, but with zero set at the lowest possible temperature, the point at which there is no heat. Zero Kelvin is 459 degrees below zero Fahrenheit. Just above this temperature, helium becomes a liquid. Anywhere close to absolute zero, and all things familiar to the normal world disappear. Molecular motion slows and then stops.
A new state of matter, called a "super atom" -- something that is neither gas nor liquid nor solid -- comes into being. But Kelvin's understanding of the strange world that exists within a few degrees of absolute zero was theoretical. By the time he died, in 1907, his colleagues were struggling to force temperatures colder than 418 degrees below zero, 41 degrees above absolute zero, and helium had not yet been liquefied.
One of the physicists who first achieved a temperature low enough for the formation of a super atom, which did not occur until 1995, had this to say: "This state could never have existed naturally anywhere in the universe, unless it is in a lab in some other solar system."
Our planet's polar explorers used, for the most part, Fahrenheit's scale, but rather than talking of degrees below zero, they often talked of "degrees of frost." One degree of frost was one degree below freezing Fahrenheit. An explorer might write in his journal of fifty degrees of frost -- eighteen degrees below zero Fahrenheit -- and in the next paragraph tell of the amputation of a frozen toe, or describe himself gnawing on a boot to stave off the starvation that so often accompanies cold, or mention in passing how he had to beat fifteen pounds of ice from the bottom of his sleeping bag before bedding down for the night. Or, after an especially cold and uncomfortable spell, he might write of the relative warmth and relief of fifty-five degrees below zero Fahrenheit.
Apsley Cherry-Garrard, who supported Robert Falcon Scott on his disastrous 1910 Antarctic expedition, did just that. "Now," he wrote, "if we tell people that to get only 87 degrees of frost can be an enormous relief they simply won't believe us." But an enormous relief it would be for one accustomed to camping at 75 degrees below zero, or 107 degrees of frost.
In his memoirs, Cherry-Garrard concurred with Dante, who placed the circles of ice beneath the circles of fire in his vision of Hell.