Quest for Ice: Polar Prospecting

On the incandescent ice between the South Pole and the sea, Paul Mayewski is digging a hole the depth and dimensions of an open grave.

Only his head, strapped into a leather flying helmet, is visible above the boundless, undulating plain of radiant snow.

First with a saw, then with a shovel, he frees blocks of snow hardened by eons of wind and heaves them to three men standing clear of the growing hollow. Nearby, three men cocooned in cold-weather gear, including a Times reporter, assemble a towering steel drill.

The seven men are the only living things across thousands of square miles in this quadrant of the West Antarctic Ice Sheet. They easily could be the first ever to tread this ice. Not even microbes can survive unaided in the arid and frigid terrain.

Mayewski, a glaciologist from the University of New Hampshire, and his team have come by airplane, snow tractor, snowmobile and wooden sled to this trackless spot in the interior of the world’s highest, windiest and coldest continent to prospect for ancient ice.

He is searching for memories preserved in the undisturbed snow.

Locked in the fragile chemistry of Antarctica’s ice fields are the faint residues of gases, isotopes and wind-borne dust that record the world’s ancient atmosphere, the changing climate and its growing pollution.

In an archive stretching back more than 20,000 years, the ice sheets record the rise and fall of the oceans, the end of the ice age, the depletion of Earth’s ozone layer and changes in the solar energy that drives worldwide weather patterns.

The chemistry also captures the dawn of industrial civilization, the advent of leaded gasoline, the detonation of the first nuclear weapons, enactment of the U.S. Clean Air Act and the steady rise of greenhouse gases in the atmosphere.

Researchers like Mayewski are reading such records of Earth’s past atmosphere to study how its climate has evolved and to predict its future.

Already the evidence they have gathered indicates that Earth’s climate is far more mercurial and dynamic than believed, prone to erratic fluctuations that might have catastrophic consequences for its most heavily populated regions.

“Without being able to go back in time, it is very hard to understand climate,” Mayewski says. “The ice cores allow us to go back in time.”

But his team first must wrest from the ice sheet the raw material of its research.

Suspended in Time

The effort leaves these men gasping.

Despite facemasks and snow goggles, their cheeks are flushed with frost burn, their eyes puffy and bloodshot from the glare of ceaseless sunlight puddled in brilliant pools on the ice. Their breath hangs in icicles off their beards and facemasks.

When they pause to eat, they share shards of frozen chocolate sharp enough to cut their lips, gnaw sticks of beef jerky and sip hot water.

Without warning, the gusting wind drops the chill this Antarctic summer day to 70 degrees below zero.

Mayewski works in a wilderness of ice 9,800 feet thick, where the natural laws that govern more moderate latitudes seem suspended. Here, it is early morning all month. A day lasts all year. The sun rises in August and sets in February.

With the suspension of temperate time, even decay and disorder seem to be held in abeyance. A seal carcass lies in a distant valley where the animal died, perfectly preserved after 3,000 years. Temporary human arrangements become permanent monuments. In an explorers’ survival hut, a table set for dinner in 1912 is undisturbed 83 years later. A penguin prepared for dissection the year the Titanic sank still awaits the surgeon’s scalpel, unspoiled.

And the natural result when molecules of hydrogen and oxygen combine is not the free-flowing fresh water of rivers and streams.

It is a six-sided, symmetrical crystal of ice.

In all, Antarctica is covered by 5.4 million square miles of interlocking glaciers and ice sheets up to three miles thick. Together they encompass an area broader than North America and Australia combined. In winter, the continent is girdled by an additional 7.7 million square miles of sea ice--twice the size of the United States.

The shield of ice that caps the continent is the world’s largest body of freshwater--containing three-quarters of Earth’s pure water, yet its frozen surface is drier than the Sahara desert. Antarctica is as cold in parts as Mars and not as well mapped as Venus.

The thick frost is so omnipresent that those who work in Antarctica rarely call the continent by its proper name.

They simply call it The Ice, and its unique character is the lure that draws Mayewski so far out onto this polar plateau.

Here, The Ice seems to be a living presence. The wind that rubs against it gives it voice.

It is acquisitive. Having absorbed a continent, it seeks to extend itself into every new object it encounters, coating it and impregnating it with ice crystals. In March, the sea ice grows at more than 22 square miles a minute. A visitor becomes painfully aware that the human body is two-thirds water, eager to freeze.

Perhaps the most noteworthy gauge of Antarctica’s contrary character is that ice and snow, ordinarily so volatile, are here the measure of eternity.

In places, the snow and ice are 500,000 years deep, in annual layers sometimes so distinct that they can be counted like tree rings.

The Right Wardrobe

Almost every American journey to The Ice begins in a clothing warehouse outside Christchurch, New Zealand.

Mayewski’s expedition onto the West Antarctic Ice Sheet is no different.

If an army travels on its stomach, the $195-million U.S. Antarctic research program survives on the contents of its closet--1,715 down parkas, 8,203 pairs of socks, 1,952 pairs of gloves, 1,341 pairs of snow goggles and 4,305 pairs of heavy long underwear.

Every year, hundreds of scientists travel under the auspices of the National Science Foundation to Antarctica. In a rite of passage, they exchange their civilian clothes for special government-issue cold-weather gear.

Almost twice as many NSF scientists and civilian workers are flying to Antarctica this season as a decade ago. With them fly five times as much cargo--almost 1,250 tons of food, equipment, mail and scientific instruments. Even more will arrive by ship in February.

A dozen nations maintain research bases here, but the National Science Foundation, with its squadron of ski-equipped cargo planes and its network of year-round bases, has made Antarctica a kind of U.S. protectorate.

For the first time in a generation, however, the NSF research program, the largest and most prolific on The Ice, is under formal review by Congress. Legislators are having second thoughts about whether the United States still has any crucial national business on the world’s most inhospitable continent.

On this day in November, Mayewski would argue that this is indeed important business.

He is traveling onto the ice sheet with two students, Karl Kreutz and Jeff Thomas; two drillers, David Giles and Geoffrey Hargreaves, and Mark Twickler, associate director of the University of New Hampshire Glacier Research Office, which Mayewski directs. For a month they will be isolated on the ice sheet, working out of three small yellow tents and a portable survival hut the size of a pantry.

They cross the Southern Ocean from New Zealand to Antarctica in the cramped cargo hold of U.S. Air Force flight “Ice 12,” landing at McMurdo Station, the main U.S. base here. At McMurdo, a crowded depot built on the side of an active volcano, NSF research teams organize their equipment for the annual journeys into the interior.

A Rare New Snowfall

Across McMurdo Station, new snow is falling.

On a continent normally too dry and too cold to support condensation--where a blizzard consists of existing snow churned violently by the wind--the appearance of new snow is a rarity.

On this sunlit night, the dusting of new crystals is barely enough to whitewash the humps of blue sea ice and McMurdo’s black volcanic hillocks.

But across almost the entire continent, it never melts.

Multiplied season after season for millennia, the weight is enough to transform the snow into glacial ice and set it moving. In some areas, the ice is almost three miles thick.

Extracted in long, narrow cores and minced into thousands of individual laboratory specimens, each ice sample offers a unique insight into the climate and the composition of the atmosphere at the time the snow formed.

From traces of ammonia, researchers estimate the amount of vegetation. Microscopic pollen grains indicate the kinds of plants. From calcium dust they guess at the extent of the world’s deserts.

Extreme levels of sulfates reveal volcanic eruptions, while sulfur dioxide reveals the burning of coal.

From the distribution of the trace chemicals, they reconstruct the ancient winds. Changes in the ratio of oxygen isotopes in each annual layer of ice reveal the average global temperature. Ancient air bubbles record the amount of carbon dioxide in the atmosphere when the snow fell. Cosmic dust hints at Earth’s journey through the universe.

Already, researchers are reading the chemical history of the world’s climate with a level of sensitivity and sophistication impossible even a decade ago.

The ice is teaching scientists that they greatly underestimated how much Earth’s temperature swings over the eons and how much greater the effects of global warming may be at the world’s polar regions.

From the preliminary evidence of Greenland’s ice--drawn from cores provided by Mayewski--scientists were startled to discover that the climate in the aftermath of the most recent ice age 15,000 years ago alternately cooled and warmed drastically within just a few years. Ice from Peru also shows evidence of more moderate, but still pronounced, climate changes in tropical latitudes, with an abrupt warming trend in the last 200 years.

Scientists also learned that even minor temperature changes might be greatly magnified at the poles. Arctic temperatures apparently soared about three times faster than in the tropics.

No one knows what factor pushed the climate over the threshold from ice age to today’s balmy conditions. And no one knows what happened at the other end of the world during the same period.

But the Greenland ice has scientists wondering whether the climate, after millennia of relative stability, may again start oscillating wildly.

New evidence from deep-sea cores gives additional weight to the idea that the Earth regularly goes through abrupt climate changes. Findings made public last month by researchers at Columbia University’s Lamont-Doherty Earth Observatory suggest that the Earth has gone through at least seven cycles of abrupt cooling and warming in the last 12,000 years. The most recent swing peaked as recently as 800 years ago.

“If this is indeed a regular climate rhythm, it is still going on today,” said paleoclimatologist Gerard Bond, who conducted the study.

“The evidence is growing that climate in the post-ice age world is not as stable and is more variable than once thought.”

Today, scientists are piecing together the information mined from glacier ice extracted from Peru, China, Tibet, Nepal, Canada, Greenland and Antarctica into an intricate planetary mosaic.

“When we started, we couldn’t convince anybody that the chemistry of an ice core was worth anything,” Mayewski said.

Following Flags Home

Since early morning, Mayewski has led the way across the ice sheet. He steers his snowmobile by staring over his shoulder at where he has been. In a world without landmarks or signposts, where a compass cannot be trusted, it is the only sure way to stay on course.

Every third of a mile for almost 50 miles, Mayewski stops his snowmobile and plants a red flag. He stays on course by lining up two or more flags behind him as he drives. He carries 500 flags on his sled.

As long as he can see more than one flag, the team can travel. When its work is done, the team will follow the flags home, like crumbs dropped in the wilderness.

Kreutz clings to the back of the wooden sled hitched to the snowmobile as the caravan bucks over the corrugated ice.

Twickler and Thomas trail a third of a mile behind them on a snowmobile towing two more wooden sleds with a ton of food and equipment. Thomas twists to keep his head--covered by a muffler, hat, hood and mask--out of the direct draft from a wind cold enough to congeal flesh.

Giles and Hargreaves follow two miles behind in an overheated, orange snow tractor, towing five more tons of gear.

The twin of their snorting diesel-powered “snow cat,” used to cross the Antarctic 38 years ago, is a museum exhibit in Christchurch.

The three teams stay well apart just in case one should fall into a crevasse.

Every six miles Mayewski and Twickler attempt to verify their position by satellite. Their readings do not agree. The liquid crystal display on Mayewski’s hand-held computer freezes.

Visibility is less than half a mile and closing.

To get even this far has been a struggle. The expedition has been dogged by bad weather and broken equipment.

To reach their proposed drill site, the team planned to fly 800 miles from McMurdo to Byrd Camp, a plywood outpost on the ice sheet, barely the size of a railroad dining car, staffed in the summer by eight men and women. They planned to travel the last 100 miles by snowmobile and tractor.

It sounded straightforward in their grant proposal.

But their first flight to Byrd Camp had to turn back when--just as the snow runway came into view--the landing skis broke. The LC-130 aircraft flew three hours back to McMurdo, the only place in Antarctica where it could make an emergency landing on wheels.

Five more times they tried to fly to Byrd Camp. Each time, the weather was so severe that the NSF canceled air operations. At the height of the worst storm, the winds exceeded 106 mph. Even when the weather cleared, the storms had buried the aircraft under so much snow it took another day to dig them out.

On the seventh try, they made it to Byrd Camp, only to lose two days to ice fogs and blowing snow.

After the weather cleared, Mayewski and his procession had traveled no more than 20 miles when he discovered that the snow tractor, hauling all the drill equipment, was getting less than half its predicted gas mileage.

Then the satellite navigation units started to malfunction intermittently.

Whipped by winds and peppered by dry snow, they continue to inch cautiously across the blazing dome of the ice.

The wind stirs a fog of dry snow that conceals their tracks. Clouds erase the horizon. Surface features and shadows vanish in the liquid light.

“It is like driving through milk,” Thomas murmurs.

What remains has no scale, depth or perspective. Washed in the same white light, the world is a glowing, blank abyss.

The ice seems to have folded in on itself.

Whiteout.

“You look up and you are lost,” Mayewski says.

Continent Is His Lab

In a few months, Mayewski will turn 50. There is already a surfeit of salt and pepper in his beard.

His life is framed by these forays onto the ice.

As an experienced mountaineer, he is among the last of those who filled in the final blanks on the map of the Antarctic. As a chemist probing the molecular constituents of ice and snow, he is among the first of a new generation of researchers who are using the continent as a laboratory to explore the forces that govern the entire planet.

Mayewski was 22 when he made his first trip to The Ice.

After his first season, he was so eager to return that when his federal grant expired, he talked his way onto a tourist cruise as a guest lecturer. Later, he persuaded an Italian millionaire to charter a windjammer for an Antarctic expedition. The trip fell through when he could not secure matching funds.

In the 27 years since, Mayewski has led 30 scientific expeditions into the world’s remote ice fields, from the Himalayan highlands to the plateaus of Antarctica, Iceland and the Greenland icecap.

“I like to be moving, to be traveling, where you are worried only about your destination,” he says.

Some Fear Meltdown

In his research, Mayewski takes for granted the constancy of the ice sheet on which he stands.

Other scientists, however, worry that the ice sheet may be poised for a catastrophic meltdown. They suspect that the global warming that ended the last ice age may only now have penetrated to the bottom of the frigid ice cap, jeopardizing its stability.

Scientists know that two-thirds of the West Antarctic Ice Sheet--today roughly the size of Texas--collapsed 20,000 years ago, about the time the last ice age ended, but scientists are locked in fierce disagreement over whether the remaining ice also will melt.

There is enough water locked in the West Antarctic Ice Sheet that, should it break up, sea level would rise 20 feet worldwide. And that could trigger an even more catastrophic collapse. Melting of the adjacent East Antarctic Ice Sheet, which is about 10 times larger, would raise sea level more than 200 feet.

Many of the world’s largest cities and most heavily populated coastal areas would be submerged.

A few fragmentary fossils--the tooth of a freshwater fish, the leg of a beetle, the petrified wood of ancient beeches--are testament to Antarctica’s warmer and wetter past.

As the Earth warms today, temperatures around the world have risen about one degree Fahrenheit since the turn of the century, but at least one region of Antarctica has been warming four times faster. Records show that the Antarctic Peninsula, just south of the tip of South America, has warmed 4.5 degrees in 50 years.

Scientists now argue whether those warmer temperatures have weakened the ice sheets on the rest of the continent.

In 1995, 400 square miles of the Antarctic ice shelf disintegrated into the sea. Two smaller ice shelves also came apart. At the same time, an iceberg the size of Connecticut broke off from the Larsen Ice Shelf, the fourth such mammoth iceberg to break off the Antarctic ice in the last decade. In 1986, Antarctica spawned two icebergs four times larger--each more than 4,000 square miles of ice.

And between 1989 and 1991, the vast ice sheet covering Bellingshausen Sea, thought to be a permanent ice shelf, simply vanished. It has since re-formed.

The erratic behavior of the five major ice streams that flow off the West Antarctic Ice Sheet today concerns other researchers. One of the five has simply stopped. For the last four years, a second major ice stream, called Icestream B, has been thinning three times faster than it is being replenished by new snow, according to Gordon Hamilton, a senior researcher at Ohio State University’s Polar Research Center.

“We were so surprised, so stunned by that result,” he said.

No one knows whether the changes are symptoms of the impending breakup of the entire ice sheet or just normal seasonal variations.

Elsewhere in the world, the ice is undeniably in retreat.

From Peru to Greenland, thousands of mountain glaciers are melting. University of Colorado researchers say the glaciers have been shrinking for decades and the rate seems to be accelerating. In some areas, such as the Alps, the glaciers have shrunk by half in the last 100 years.

The permafrost that underlies much of Alaska is thawing. The ice of the Arctic Ocean is shrinking. Throughout the Northern Hemisphere, sea ice and snow cover have reached record lows, the Colorado researchers say.

Many experts now are convinced that human activities have accelerated global warming. Ironically, some EPA researchers are counting on Antarctic ice to maintain the equilibrium of the world’s oceans as temperatures continue to rise, staving off any dangerous increase in sea level at least for the next century or so.

They acknowledge that warmer global temperatures are likely to increase the amount of ice melting off Antarctica. But they predict that one effect of warmer climate will be greater annual snowfall in Antarctica.

More snow will mean more ice, and more ice will lock up enough more freshwater--more than enough, they believe, to offset any rise in sea level due to melting caused by global warming.

Whatever the truth, the uncertainty about the ice sheet persists despite generations of intense investigation.

In recent decades, NSF researchers have laid bare Antarctica’s interior with satellite sensors and airborne radars. With video cameras and interactive television, they have brought the world’s most remote environment into America’s living rooms; with computers and satellite links, they have turned it into a node on the Internet--a virtual Antarctica--where only the play of fingers on a keyboard separates third-graders in Pasadena from astronomers at the South Pole.

They have uncovered Antarctica’s central role in maintaining the planet’s well-being. They have discovered that it is an engine of global weather, a wellspring of its oceans, and a repository of its atmosphere.

But the ice has yet to yield its mystery.

Crystal Specimens

Mayewski has finished digging.

Now Kreutz squats at the bottom of the snow pit.

To avoid tainting the ice with his breath or perspiration, he wears a hooded, white cotton suit, plastic gloves and a facemask. The snow crystals he seeks, like the ice cores, must be kept pristine or the information they contain will be lost.

Meticulously, Kreutz works his way down the face of the pit, stopping every inch to sample the dense crystals.

When the drill has been assembled, they will bore even deeper into the ice sheet, encompassing a record of the atmosphere for the last 200 years. It may take them years at their home laboratory in New Hampshire to analyze the cores.

Eventually, Mayewski hopes to crisscross the continent with such cores, to assemble a comprehensive picture of how climate has changed since the Industrial Revolution.

Giles, a man who wears suspenders and a belt, has brought two drills.

Both break.

If he cannot repair the drills, the expedition will lose the opportunity it has traveled so far to secure. With nothing more than the tools he carries with him and the ice itself for a workbench, he disassembles their electric motors in the freezing wind. After two days, he gets one drill working again.

He guides the spinning drill head down deep into the ice, then--satisfied now--up out of the new bore hole in the ice sheet.

The men gaze down.

The cavity in the ice left by the drill glows with its own light, encompassing the entire spectrum of blue, from bluish white at its outer edges through sapphire and shades of cobalt to the darkest interstellar blue.

They peer into the hidden heart of the world.

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Tales the Ice Tells

Antarctica is capped by ice sheets almost three miles thick. By drilling cores into the ice, National Science Foundation researchers can read a unique record of the atmosphere, past climate, volcanic eruptions, and human global pollution.

1. Ice from Byrd shows how the atmosphere has changed since the Industrial Revolution.

2. Ice from the South Pole reveals evidence of the Chernobyl nuclear accident.

3. Ice from Vostok links changes in the level of greenhouse gases to changes in world temperatures.

4. Every year, the sea ice effectively doubles the size of Antartica by adding up to 7.7 million squares miles of ice in a belt around the continent.