Arctic Dreams, page 23
5 Glacial periods are relatively rare in the earth’s history. Scientists have discovered only four in the last 600 million years, the last of which is still going on. The Holocene, as far as we know, is only an interglacial stage, a reprieve, between the retreat of the Wisconsin ice (or Würm ice in Europe) and the next glacial advance.
6 Eskimo descriptions of this phenomenon were not taken seriously until 1982, when archaeologists working at Utqiagvik, a prehistoric village site near Barrow, Alaska, discovered a family of five people that had been crushed to death in such an incident.
7 The Mousterian tradition, named for tools discovered near Le Moustier in the Dordogne in France, marks the high point of Neanderthal culture in the Middle Paleolithic, 40,000 to 100,000 years ago. See chart, Appendix III.
8 The Aurignacian was one of several traditions that emerged in the upper Paleolithic in western Europe between ten and forty thousand years ago, when Cro-Magnon people displaced the Neanderthal culture.
9 The umiak, a Thule invention, is an open, walrus- or bearded seal-skin boat, about 30 feet long, sometimes fitted with a square sail and a single, stepped mast. On long journeys it was commonly rowed by women, while the men followed in shorter, lower, decked-over, single-seat, and more seaworthy kayaks, free to hunt. For this reason the boat is also called “a women’s boat.”
10 The materials they worked with, of course, came almost entirely from the animals they hunted. Eskimos generally regarded these materials as gifts given in accordance with ethical obligations they felt toward the animals. The two parallel cultures, human and animal, were linked in biological ways and, for the Eskimo, in spiritual ways that are all but lost to our understanding today. It was the gift rather than the death that was preeminent in the Eskimo view of hunting.
11 It is easy to impugn the worth of such nebulous virtues, and to find among the interlopers venal and self-aggrandizing people. But it disparages Eskimos to see them as helpless in this situation. Most Eskimos are not opposed to changing their way of life, but they want the timing and the direction of change to be of their own choosing. “There is no insistence,” a man once told me, “on living as hard a life as possible.” In passing, it should be noted that many people have offered genuine assistance to Eskimos. One frequently hears praise in the Canadian Arctic, for example, for Catholic missionaries, because of their long-term commitment to a single village, their practice of learning to speak the language and to hunt, and their emphasis on good schooling.
12 For a list of publications that grew out of work with the Nunamiut, see note 4.
Six
Ice and Light
THE RADIO REPORT THE evening before had been terse and ominous: gale warnings for the northern Labrador Sea. Our apprehension was over more than heavy seas, however. There were icebergs ahead—and we would be steaming into those waters in darkness, straight into a picket line of ice the size of cathedrals, borne slowly south on the Canadian Current. Implacable icebergs from the tidewater glaciers of West Greenland, the towering, gray marble walls at Savissivik and Torsukattak and Upernavik. But in those heavy seas, we knew, the ship’s radar would not be able to distinguish even those fifty times larger than the ship from the wild crests of windblown waves.
The heavily laden vessel, the MV Soodoc1 carrying equipment and a year’s supplies to an arctic mine, plowed resolutely into the dark water, taking spray over her bows. The wind vibrated cables until they moaned; it wailed through the ship’s deck cranes. Waves began to wash over us amidships. The crew secured portholes and hatches on the ship’s upper deck and prepared for the violent pitching and rolling to come.
We passed into Davis Strait in peace. The storm passed us to port and fell away behind, one of those strange reprieves that leave you in momentary disbelief.
In the morning I stood in the bow, watching the ship’s prow split smoothly the six-foot swell of green-black water. Looming in the fog, those ice massifs that had left some of us sleepless were moving inexorably south, wreathed in gray silence, inchoate in the cold air. If we had but touched last night, the ship would have been torn by the noise of alarms and Klaxon. We would have bolted up the companionways in our storm gear for the tiny lifeboats, hobbled by half-donned clothing, brought down to the raw edge of life. Lowering away into ice and darkness in 20-foot seas, terror like a wild dog in your chest.
We passed in peace. I stared at the dark swell and thought how gently is the sparrow held that lights on a ship at sea. And then went aft, for the first meal of the day.
Montreal was far behind us. We were on the stretch, bound for the Northwest Passage; cutting the same water, seeing the same colors and animals and clear currents that Frobisher and Davis and Baffin had seen. Which is why I had asked to come. And to see the ice that had silenced them all. If I had a desire simply to be with anything in the North, it was to be with icebergs. I do not know if I had had this wish for years or if it only intensified as the prospect of the voyage loomed. But when I saw them, it was as though I had been waiting quietly for a very long time, as if for an audience with the Dalai Lama.
On the afternoon of the day we knew the storm had passed, I stood on the starboard side of the bridge at a window, with the heavy protective glass lowered. I rested my forearms on the sill, feeling the warmth of the bridge heaters around my legs and a slipstream of cool air past my face. The first icebergs we had seen, just north of the Strait of Belle Isle, listing and guttered by the ocean, seemed immensely sad, exhausted by some unknown calamity. We sailed past them. Farther north they began to seem like stragglers fallen behind an army, drifting, self-absorbed, in the water, bleak and immense. It was as if they had been borne down from a world of myth, some Götterdämmerung of noise and catastrophe. Fallen pieces of the moon.
Farther to the north they stood on their journeys with greater strength. They were monolithic; their walls, towering and abrupt, suggested Potala Palace at Lhasa in Tibet, a mountainous architecture of ascetic contemplation. We would pass between them, separated from them by no more than half a mile. I would walk from one side of the ship to the other, wondering how something so imposing in its suggestion of life could be approached so closely, and yet still seem so remote. It was like standing in a dirigible off Annapurna and Everest in the Himalayas.
The suggestion of life around them was not an illusion. Harp seals and flocks of seabirds were drawn to fish schooling in the nutrient-rich waters at their base—an upwelling driven by freshwater runoff from the iceberg, pouring into the lighter water of the salty ocean. With my binoculars I could follow the scarves of turquoise meltwater unfurling 400 feet to the sea.
I occasionally drew back from the starboard window to make a sketch, or to bring the binoculars up to my eyes. I marveled as much at the behavior of light around the icebergs as I did at their austere, implacable progress through the water. They took their color from the sun, and from the clouds and the water. But they also took their dimensions from the light: the stronger and more direct it was, the greater the contrast upon the surface of the ice, of the ice itself with the sea. And the more finely etched were the dull surfaces of their walls. The bluer the sky, the brighter their outline against it.
I wrote words down for the tints—the grays of doves and pearls, of smoke. Isolated in my binoculars, the high rampart of a mesa-like berg seemed sheared off like a wall of damp talc. Another rounded off smoothly, like a human forehead against the sky, and was pocked and lined, the pattern of a sperm whale’s lacerated tun. Floating, orographic landscapes—sections broken out of a mountain range: snow-covered ridges, cirque valleys, sharp peaks. The steep walls often fell sheer to the sea, like granite pitches, their surfaces faceted like raw jade, or coarser, like abraded obsidian.
Where the walls entered the water, the surf pounded them, creating caverns, grottoes, and ice bridges, strengthening an impression of sea cliffs. At the waterline the ice gleamed aquamarine against its own gray-white walls above. Where meltwater had filled cracks or made ponds, the pools and veins were milk-blue, or shaded to brighter marine blues, depending on the thickness of the ice. If the iceberg had recently fractured, its new face glistened greenish blue—the greens in the older, weathered faces were grayer. In twilight the ice took on the colors of the sun: rose, reddish yellows, watered purples, soft pinks. The ice both reflected the light and trapped it within its crystalline corners and edges, where it intensified.
The burden of rocks, gravel, silt, and sand that icebergs carry within them streaks their sides; as they melt, they rise higher in the water and the debris in their shoal water creates a series of waterline marks. As they fracture and tilt, the patterns of waterline marks cross at odd angles and slant skyward.
It seemed almost superfluous, but the third mate took the measure of one with his sextant: 64.7 meters high by 465.4 meters long (212.27 by 1526.88 feet). Another is 70.4 meters high by 371.0 meters long (230.97 by 1217.19 feet); but the numbers cannot encompass them. The ice reaches far below the surface of the water and stretches away in a third dimension. It is impossible to know how much of it lies beneath the water—four-fifths of its height and seven-eighths of its mass is the mariner’s general rule. And the shape of each one changes as our ship passes. New valleys, slopes of wind-packed snow, ramparts and spires, and columnar bluffs come into view. Another set of measurements of the same iceberg turns out differently.
One day, low decks of cumulus clouds bearing off to the southeast open up a horizon to the west and north. In brilliant sunshine the icebergs now gleam as crisp a blinding white in the black water as storm-lit sails. After a while icebergs near the horizon break with the surface of the ocean to float low in the pale blue sky. Four or five of them, distant mirages, not seeming to take the moment seriously at all. I return, smiling, to those immediately before me, and renew my faulty sketching. I remember the church at Ranchos de Taos, New Mexico, Saint Francis of Assisi; photographers have gone there for decades, impassioned with a desire to render it in shades of black and white only. What would an Edward Weston or a Wynn Bullock or a Paul Strand have thought of these? I stare for hours from the starboard window at these creatures I have never seen before. They drift past in the spanking, beautiful weather. How utterly still, unorthodox, and wondrous they seem.
In the interior of Greenland the Wisconsin Ice Age continues, as it were, unabated. The Greenland ice cap, forming continuously from layers of compacted snow and trapped air and expanding at varying rates, is 1500 miles long, 450 miles wide, and up to 11,000 feet thick. It bears down with such force that the center of the island is warped some 1180 feet below sea level. The glacial tongues and margins of the ice cap reach the sea at several prominent points, where enormous sections of ice break off and float away in the currents. One of the most imposing of them is the 400-foot-high palisade of Humboldt Glacier, which stretches north and south for 50 miles at the edge of Kane Basin.
Most of the icebergs of the Northern Hemisphere are calved from the western glaciers of the Greenland ice cap, into Disko and Melville bays. They drift north in the West Greenland Current for a while and then come south that year or the next with the Canadian Current to the Labrador Sea. As imposing as they are, icebergs are dwarfed by ice islands, a kind of ice calved along the north coast of Greenland and the northwest coast of Ellesmere Island from ice shelves that extend offshore into embayments of the ocean. (The structure and behavior of shelf ice have been likened to those of both glacial ice and sea ice, though strictly speaking it is neither.) These ice islands, up to 300 square miles in extent but only 150 to 165 feet thick, become incorporated in the polar ice pack, where they make ideal, long-term drift bases for scientific research. They are structurally sound, and their flat tops, uniformly corrugated like a tin roof, offer a working platform close to the surface of the water. (Fletcher’s Ice Island [T-3], a 50-square-mile platform spawned from the Ward Hunt Ice Shelf at Disraeli Fiord, Ellesmere Island, was used by scientific parties for twenty-five years before work there was terminated in the mid-1970s.) Ice islands normally drift for decades in the ice gyre north of Alaska before being caught, finally, in the East Greenland Current, in whose waters they eventually disintegrate and melt.
Almost as extensive as ice islands but much thicker are tabular icebergs, which break off whole from the foot of a tidewater glacier. With a volume of 40 or 50 cubic miles, they are the largest objects afloat in the Northern Hemisphere. Other sorts of freshwater arctic ice include the ice that forms on arctic rivers and on tundra lakes and ponds (which may freeze to the bottom in winter), and the lenses and wedges of ground ice within permafrost. The latter influence the formation of a distinctive geometry of frost cracks in the tundra called “patterned ground,” and raise the hemispherical mounds, or frost boils, called pingos. (A well-known cluster of some 150 pingos, from 3000 to 5000 years old, rises near Toker Point, just east of the mouth of the Mackenzie River.)2
The sea ice that forms on the surface of the ocean behaves in less predictable ways than freshwater ice, depending on how it is formed and altered and on how old it is. Its physics—the distribution of forces within it, the range of its elasticity and plasticity, the structural quality of its crystal lattices—is highly complex. “Scarcely a substance on earth,” writes one scientist, “is so tractable, so unexpectedly complicated, so deceptively passive.”
Freshwater ice usually begins to crystallize at 39.2°F, the temperature at which fresh water is densest. Sea ice does not achieve its maximum density, or start freezing, until it is cooled to 28.6°F. In its initial stages, the crystalline structure of sea ice incorporates brine and is not solid. It will therefore bend under a load before it fractures, while newly formed freshwater ice, brittle and also more transparent, will fracture suddenly, like a windowpane. (Because of its elasticity, even sea ice four inches thick is unsafe to walk on, while freshwater ice only half as thick will support a human being.)
In the absence of any wind or strong current, sea ice first appears on the surface as an oily film of crystals. This frazil ice thickens to a kind of gray slush called grease ice, which then thickens vertically to form an elastic layer of ice crystals an inch or so thick called nilas. Young nilas bends like watered silk over a light ocean swell and is nearly transparent (i.e., dark like the water). When it is about four inches thick, nilas begins to turn gray and is called young ice, or gray ice. When gray ice finally becomes opaque it is called first-year ice. And in these later stages it thickens more slowly.
By spring, first-year ice might be four to six feet thick. If it doesn’t melt completely during the summer, it becomes second-year ice in the fall, tinted blue and much harder. (Brine in the upper layers has drained out during the summer and fresh ice crystals have filled the interstices.) Second-year ice continues to thicken, until it stabilizes after a few years at about 10 to 12 feet. If it remains unmelted through a second summer, it is simply called multiyear ice, or polar pack ice, to distinguish it from first- and second-year pack ice.3 A more formidable version of multiyear ice, paleocrystic ice, forms in the open polar sea and may be 50 feet thick.
Pack ice may be consolidated in great expanses of rubble called field ice, or broken up by lanes of open water (leads) to a lesser or greater degree, creating various types of close and open pack ice—for example “close pack” (seven-tenths to nine-tenths coverage of the sea).4
Winds and currents almost always affect the formation of sea ice. If a swell comes up in a sludge of grease ice, for example, the crystals congeal in large, round plates that develop upturned edges from bumping against each other—a stage called pancake ice. If nilas is broken up by the wind, the separate sheets often ride up over each other in a characteristic interlocking pattern called finger-rafting. Heavier ice may ride up cleanly over itself or create low ridges of rubble or piles of crumbled fragments as it grinds against itself. Weathered by wind-driven snow, this debris forms rounded hills called hummocks. Ice of sufficient thickness, fractured by wind, tide, and currents and then driven in on itself by these same forces, may create a huge riprap of rubble, 20 to 40 feet high and extending as far below the ice, called a pressure ridge.
Wind and current affect sea ice formation to such an extent that very little smooth ice occurs anywhere in the Arctic except in bays and along shallow coastlines. In spring the ice surface develops puddles and melt holes (often at old aglus) and a complex pattern of surface drainage. Second-year ice is likely to produce needle ice at the bottom of these melt pools, sharp spikes diligently avoided by men, dogs, and bears. In the upper layer of first-year ice that has been drained of brine candle ice sometimes forms, which tinkles like a glass chandelier as it collapses before a gust of wind or at the touch of a hand.
Because sea ice responds to wind and current and because winds and currents have predominant patterns, researchers look for the same kind of sea ice to form in the same places every year. In Coronation Gulf, where winds and currents are light, the ice may be unusually smooth for many miles in every direction. In Nares Strait (Kennedy Channel, Hall Basin, and Robeson Channel) between Ellesmere Island and Greenland, multiyear ice driven down from the north piles up in ridges 80 feet high, a violently fractured landscape that extends north and west to the extremely rugged ice of the Lincoln Sea.
The variety of ice types and the many patterns of its fracture and dislocation amaze a first-time visitor. What could become as ordinary underfoot as soil or rock remains as exotic as the surface of another planet. When nilas sags beneath you, your legs have no idea what to do. If you are forced to cross a series of pressure ridges with a heavy sledge, or must fight constantly to keep a small boat from being crushed in moving pack ice, you have difficulty imagining any landscape more exhausting or humbling.
Flying over the ice is an easy way to appreciate its tectonic activity on a larger scale, to better understand it as the never-quite-settled surface of the Arctic Ocean. From above, the finger-rafting of huge, transparent sheets of nilas seems like a delicate and regular joinery of panes of glass. The rafting of sheets of young nilas creates a pattern of scattered, altostratus-like shapes. Dark ice cakes below prove to be ones covered with epontic algae and flipped over by animals, or places where walrus have hauled out, rested, and defecated. Long streaks of gray-white ice cutting across a broad, snow-covered expanse show where leads have recently frozen over. A low pressure ridge may lead to a dark hole and a patch of reddish snow, a polar bear kill. Streamers of grease ice in patches of open water line up with the wind. In winter the leads steam with frost smoke where the (relatively) warm water meets the frigid air.
6 Eskimo descriptions of this phenomenon were not taken seriously until 1982, when archaeologists working at Utqiagvik, a prehistoric village site near Barrow, Alaska, discovered a family of five people that had been crushed to death in such an incident.
7 The Mousterian tradition, named for tools discovered near Le Moustier in the Dordogne in France, marks the high point of Neanderthal culture in the Middle Paleolithic, 40,000 to 100,000 years ago. See chart, Appendix III.
8 The Aurignacian was one of several traditions that emerged in the upper Paleolithic in western Europe between ten and forty thousand years ago, when Cro-Magnon people displaced the Neanderthal culture.
9 The umiak, a Thule invention, is an open, walrus- or bearded seal-skin boat, about 30 feet long, sometimes fitted with a square sail and a single, stepped mast. On long journeys it was commonly rowed by women, while the men followed in shorter, lower, decked-over, single-seat, and more seaworthy kayaks, free to hunt. For this reason the boat is also called “a women’s boat.”
10 The materials they worked with, of course, came almost entirely from the animals they hunted. Eskimos generally regarded these materials as gifts given in accordance with ethical obligations they felt toward the animals. The two parallel cultures, human and animal, were linked in biological ways and, for the Eskimo, in spiritual ways that are all but lost to our understanding today. It was the gift rather than the death that was preeminent in the Eskimo view of hunting.
11 It is easy to impugn the worth of such nebulous virtues, and to find among the interlopers venal and self-aggrandizing people. But it disparages Eskimos to see them as helpless in this situation. Most Eskimos are not opposed to changing their way of life, but they want the timing and the direction of change to be of their own choosing. “There is no insistence,” a man once told me, “on living as hard a life as possible.” In passing, it should be noted that many people have offered genuine assistance to Eskimos. One frequently hears praise in the Canadian Arctic, for example, for Catholic missionaries, because of their long-term commitment to a single village, their practice of learning to speak the language and to hunt, and their emphasis on good schooling.
12 For a list of publications that grew out of work with the Nunamiut, see note 4.
Six
Ice and Light
THE RADIO REPORT THE evening before had been terse and ominous: gale warnings for the northern Labrador Sea. Our apprehension was over more than heavy seas, however. There were icebergs ahead—and we would be steaming into those waters in darkness, straight into a picket line of ice the size of cathedrals, borne slowly south on the Canadian Current. Implacable icebergs from the tidewater glaciers of West Greenland, the towering, gray marble walls at Savissivik and Torsukattak and Upernavik. But in those heavy seas, we knew, the ship’s radar would not be able to distinguish even those fifty times larger than the ship from the wild crests of windblown waves.
The heavily laden vessel, the MV Soodoc1 carrying equipment and a year’s supplies to an arctic mine, plowed resolutely into the dark water, taking spray over her bows. The wind vibrated cables until they moaned; it wailed through the ship’s deck cranes. Waves began to wash over us amidships. The crew secured portholes and hatches on the ship’s upper deck and prepared for the violent pitching and rolling to come.
We passed into Davis Strait in peace. The storm passed us to port and fell away behind, one of those strange reprieves that leave you in momentary disbelief.
In the morning I stood in the bow, watching the ship’s prow split smoothly the six-foot swell of green-black water. Looming in the fog, those ice massifs that had left some of us sleepless were moving inexorably south, wreathed in gray silence, inchoate in the cold air. If we had but touched last night, the ship would have been torn by the noise of alarms and Klaxon. We would have bolted up the companionways in our storm gear for the tiny lifeboats, hobbled by half-donned clothing, brought down to the raw edge of life. Lowering away into ice and darkness in 20-foot seas, terror like a wild dog in your chest.
We passed in peace. I stared at the dark swell and thought how gently is the sparrow held that lights on a ship at sea. And then went aft, for the first meal of the day.
Montreal was far behind us. We were on the stretch, bound for the Northwest Passage; cutting the same water, seeing the same colors and animals and clear currents that Frobisher and Davis and Baffin had seen. Which is why I had asked to come. And to see the ice that had silenced them all. If I had a desire simply to be with anything in the North, it was to be with icebergs. I do not know if I had had this wish for years or if it only intensified as the prospect of the voyage loomed. But when I saw them, it was as though I had been waiting quietly for a very long time, as if for an audience with the Dalai Lama.
On the afternoon of the day we knew the storm had passed, I stood on the starboard side of the bridge at a window, with the heavy protective glass lowered. I rested my forearms on the sill, feeling the warmth of the bridge heaters around my legs and a slipstream of cool air past my face. The first icebergs we had seen, just north of the Strait of Belle Isle, listing and guttered by the ocean, seemed immensely sad, exhausted by some unknown calamity. We sailed past them. Farther north they began to seem like stragglers fallen behind an army, drifting, self-absorbed, in the water, bleak and immense. It was as if they had been borne down from a world of myth, some Götterdämmerung of noise and catastrophe. Fallen pieces of the moon.
Farther to the north they stood on their journeys with greater strength. They were monolithic; their walls, towering and abrupt, suggested Potala Palace at Lhasa in Tibet, a mountainous architecture of ascetic contemplation. We would pass between them, separated from them by no more than half a mile. I would walk from one side of the ship to the other, wondering how something so imposing in its suggestion of life could be approached so closely, and yet still seem so remote. It was like standing in a dirigible off Annapurna and Everest in the Himalayas.
The suggestion of life around them was not an illusion. Harp seals and flocks of seabirds were drawn to fish schooling in the nutrient-rich waters at their base—an upwelling driven by freshwater runoff from the iceberg, pouring into the lighter water of the salty ocean. With my binoculars I could follow the scarves of turquoise meltwater unfurling 400 feet to the sea.
I occasionally drew back from the starboard window to make a sketch, or to bring the binoculars up to my eyes. I marveled as much at the behavior of light around the icebergs as I did at their austere, implacable progress through the water. They took their color from the sun, and from the clouds and the water. But they also took their dimensions from the light: the stronger and more direct it was, the greater the contrast upon the surface of the ice, of the ice itself with the sea. And the more finely etched were the dull surfaces of their walls. The bluer the sky, the brighter their outline against it.
I wrote words down for the tints—the grays of doves and pearls, of smoke. Isolated in my binoculars, the high rampart of a mesa-like berg seemed sheared off like a wall of damp talc. Another rounded off smoothly, like a human forehead against the sky, and was pocked and lined, the pattern of a sperm whale’s lacerated tun. Floating, orographic landscapes—sections broken out of a mountain range: snow-covered ridges, cirque valleys, sharp peaks. The steep walls often fell sheer to the sea, like granite pitches, their surfaces faceted like raw jade, or coarser, like abraded obsidian.
Where the walls entered the water, the surf pounded them, creating caverns, grottoes, and ice bridges, strengthening an impression of sea cliffs. At the waterline the ice gleamed aquamarine against its own gray-white walls above. Where meltwater had filled cracks or made ponds, the pools and veins were milk-blue, or shaded to brighter marine blues, depending on the thickness of the ice. If the iceberg had recently fractured, its new face glistened greenish blue—the greens in the older, weathered faces were grayer. In twilight the ice took on the colors of the sun: rose, reddish yellows, watered purples, soft pinks. The ice both reflected the light and trapped it within its crystalline corners and edges, where it intensified.
The burden of rocks, gravel, silt, and sand that icebergs carry within them streaks their sides; as they melt, they rise higher in the water and the debris in their shoal water creates a series of waterline marks. As they fracture and tilt, the patterns of waterline marks cross at odd angles and slant skyward.
It seemed almost superfluous, but the third mate took the measure of one with his sextant: 64.7 meters high by 465.4 meters long (212.27 by 1526.88 feet). Another is 70.4 meters high by 371.0 meters long (230.97 by 1217.19 feet); but the numbers cannot encompass them. The ice reaches far below the surface of the water and stretches away in a third dimension. It is impossible to know how much of it lies beneath the water—four-fifths of its height and seven-eighths of its mass is the mariner’s general rule. And the shape of each one changes as our ship passes. New valleys, slopes of wind-packed snow, ramparts and spires, and columnar bluffs come into view. Another set of measurements of the same iceberg turns out differently.
One day, low decks of cumulus clouds bearing off to the southeast open up a horizon to the west and north. In brilliant sunshine the icebergs now gleam as crisp a blinding white in the black water as storm-lit sails. After a while icebergs near the horizon break with the surface of the ocean to float low in the pale blue sky. Four or five of them, distant mirages, not seeming to take the moment seriously at all. I return, smiling, to those immediately before me, and renew my faulty sketching. I remember the church at Ranchos de Taos, New Mexico, Saint Francis of Assisi; photographers have gone there for decades, impassioned with a desire to render it in shades of black and white only. What would an Edward Weston or a Wynn Bullock or a Paul Strand have thought of these? I stare for hours from the starboard window at these creatures I have never seen before. They drift past in the spanking, beautiful weather. How utterly still, unorthodox, and wondrous they seem.
In the interior of Greenland the Wisconsin Ice Age continues, as it were, unabated. The Greenland ice cap, forming continuously from layers of compacted snow and trapped air and expanding at varying rates, is 1500 miles long, 450 miles wide, and up to 11,000 feet thick. It bears down with such force that the center of the island is warped some 1180 feet below sea level. The glacial tongues and margins of the ice cap reach the sea at several prominent points, where enormous sections of ice break off and float away in the currents. One of the most imposing of them is the 400-foot-high palisade of Humboldt Glacier, which stretches north and south for 50 miles at the edge of Kane Basin.
Most of the icebergs of the Northern Hemisphere are calved from the western glaciers of the Greenland ice cap, into Disko and Melville bays. They drift north in the West Greenland Current for a while and then come south that year or the next with the Canadian Current to the Labrador Sea. As imposing as they are, icebergs are dwarfed by ice islands, a kind of ice calved along the north coast of Greenland and the northwest coast of Ellesmere Island from ice shelves that extend offshore into embayments of the ocean. (The structure and behavior of shelf ice have been likened to those of both glacial ice and sea ice, though strictly speaking it is neither.) These ice islands, up to 300 square miles in extent but only 150 to 165 feet thick, become incorporated in the polar ice pack, where they make ideal, long-term drift bases for scientific research. They are structurally sound, and their flat tops, uniformly corrugated like a tin roof, offer a working platform close to the surface of the water. (Fletcher’s Ice Island [T-3], a 50-square-mile platform spawned from the Ward Hunt Ice Shelf at Disraeli Fiord, Ellesmere Island, was used by scientific parties for twenty-five years before work there was terminated in the mid-1970s.) Ice islands normally drift for decades in the ice gyre north of Alaska before being caught, finally, in the East Greenland Current, in whose waters they eventually disintegrate and melt.
Almost as extensive as ice islands but much thicker are tabular icebergs, which break off whole from the foot of a tidewater glacier. With a volume of 40 or 50 cubic miles, they are the largest objects afloat in the Northern Hemisphere. Other sorts of freshwater arctic ice include the ice that forms on arctic rivers and on tundra lakes and ponds (which may freeze to the bottom in winter), and the lenses and wedges of ground ice within permafrost. The latter influence the formation of a distinctive geometry of frost cracks in the tundra called “patterned ground,” and raise the hemispherical mounds, or frost boils, called pingos. (A well-known cluster of some 150 pingos, from 3000 to 5000 years old, rises near Toker Point, just east of the mouth of the Mackenzie River.)2
The sea ice that forms on the surface of the ocean behaves in less predictable ways than freshwater ice, depending on how it is formed and altered and on how old it is. Its physics—the distribution of forces within it, the range of its elasticity and plasticity, the structural quality of its crystal lattices—is highly complex. “Scarcely a substance on earth,” writes one scientist, “is so tractable, so unexpectedly complicated, so deceptively passive.”
Freshwater ice usually begins to crystallize at 39.2°F, the temperature at which fresh water is densest. Sea ice does not achieve its maximum density, or start freezing, until it is cooled to 28.6°F. In its initial stages, the crystalline structure of sea ice incorporates brine and is not solid. It will therefore bend under a load before it fractures, while newly formed freshwater ice, brittle and also more transparent, will fracture suddenly, like a windowpane. (Because of its elasticity, even sea ice four inches thick is unsafe to walk on, while freshwater ice only half as thick will support a human being.)
In the absence of any wind or strong current, sea ice first appears on the surface as an oily film of crystals. This frazil ice thickens to a kind of gray slush called grease ice, which then thickens vertically to form an elastic layer of ice crystals an inch or so thick called nilas. Young nilas bends like watered silk over a light ocean swell and is nearly transparent (i.e., dark like the water). When it is about four inches thick, nilas begins to turn gray and is called young ice, or gray ice. When gray ice finally becomes opaque it is called first-year ice. And in these later stages it thickens more slowly.
By spring, first-year ice might be four to six feet thick. If it doesn’t melt completely during the summer, it becomes second-year ice in the fall, tinted blue and much harder. (Brine in the upper layers has drained out during the summer and fresh ice crystals have filled the interstices.) Second-year ice continues to thicken, until it stabilizes after a few years at about 10 to 12 feet. If it remains unmelted through a second summer, it is simply called multiyear ice, or polar pack ice, to distinguish it from first- and second-year pack ice.3 A more formidable version of multiyear ice, paleocrystic ice, forms in the open polar sea and may be 50 feet thick.
Pack ice may be consolidated in great expanses of rubble called field ice, or broken up by lanes of open water (leads) to a lesser or greater degree, creating various types of close and open pack ice—for example “close pack” (seven-tenths to nine-tenths coverage of the sea).4
Winds and currents almost always affect the formation of sea ice. If a swell comes up in a sludge of grease ice, for example, the crystals congeal in large, round plates that develop upturned edges from bumping against each other—a stage called pancake ice. If nilas is broken up by the wind, the separate sheets often ride up over each other in a characteristic interlocking pattern called finger-rafting. Heavier ice may ride up cleanly over itself or create low ridges of rubble or piles of crumbled fragments as it grinds against itself. Weathered by wind-driven snow, this debris forms rounded hills called hummocks. Ice of sufficient thickness, fractured by wind, tide, and currents and then driven in on itself by these same forces, may create a huge riprap of rubble, 20 to 40 feet high and extending as far below the ice, called a pressure ridge.
Wind and current affect sea ice formation to such an extent that very little smooth ice occurs anywhere in the Arctic except in bays and along shallow coastlines. In spring the ice surface develops puddles and melt holes (often at old aglus) and a complex pattern of surface drainage. Second-year ice is likely to produce needle ice at the bottom of these melt pools, sharp spikes diligently avoided by men, dogs, and bears. In the upper layer of first-year ice that has been drained of brine candle ice sometimes forms, which tinkles like a glass chandelier as it collapses before a gust of wind or at the touch of a hand.
Because sea ice responds to wind and current and because winds and currents have predominant patterns, researchers look for the same kind of sea ice to form in the same places every year. In Coronation Gulf, where winds and currents are light, the ice may be unusually smooth for many miles in every direction. In Nares Strait (Kennedy Channel, Hall Basin, and Robeson Channel) between Ellesmere Island and Greenland, multiyear ice driven down from the north piles up in ridges 80 feet high, a violently fractured landscape that extends north and west to the extremely rugged ice of the Lincoln Sea.
The variety of ice types and the many patterns of its fracture and dislocation amaze a first-time visitor. What could become as ordinary underfoot as soil or rock remains as exotic as the surface of another planet. When nilas sags beneath you, your legs have no idea what to do. If you are forced to cross a series of pressure ridges with a heavy sledge, or must fight constantly to keep a small boat from being crushed in moving pack ice, you have difficulty imagining any landscape more exhausting or humbling.
Flying over the ice is an easy way to appreciate its tectonic activity on a larger scale, to better understand it as the never-quite-settled surface of the Arctic Ocean. From above, the finger-rafting of huge, transparent sheets of nilas seems like a delicate and regular joinery of panes of glass. The rafting of sheets of young nilas creates a pattern of scattered, altostratus-like shapes. Dark ice cakes below prove to be ones covered with epontic algae and flipped over by animals, or places where walrus have hauled out, rested, and defecated. Long streaks of gray-white ice cutting across a broad, snow-covered expanse show where leads have recently frozen over. A low pressure ridge may lead to a dark hole and a patch of reddish snow, a polar bear kill. Streamers of grease ice in patches of open water line up with the wind. In winter the leads steam with frost smoke where the (relatively) warm water meets the frigid air.
