COLUMN ONE : Glacier Ice Has an Old Tale to Tell : It’s the Rosetta Stone of the global warming mystery. Researchers in Greenland drill for a frozen core to study 200,000 years of Earth’s climate.

Atop the Greenland ice sheet, 400 miles northeast of this old supply base for Arctic radar installations, the temperature dips far below zero even in the brilliant round-the-clock sunlight of midsummer.

The winter snow never melts, and the accumulation of 200,000 years of it is now compressed into an ice sheet that reaches a depth of 10,000 feet. Ordinarily, there is no life out there in the white, silent empty wilderness. A lost, exhausted sea gull occasionally lands, and inevitably perishes. Otherwise, all that moves is the wind, whipping the new snow into whimsical patterns across the 708,000 square miles of the Northern Hemisphere’s greatest glacier.

But last summer, two teams of scientists pitched camp--Europeans at the glacier’s summit, the Americans some 15 miles away--on audacious missions to drill all the way to the underlying bedrock and to preserve a pristine core of the ice sheet from top to bottom. They left ahead of the enveloping freeze of autumn darkness, but now they are back in force, living in huts and working in computer-equipped laboratories carved out of the ice and supplied by thundering cargo planes on skis.

Amid heightened concerns worldwide about the environment, ice-coring has suddenly become a high-priority, high-visibility--and high-pressure--scientific endeavor. Glacier ice, long treasured by climatologists, has taken on a new prominence as the Rosetta Stone of the global warming mystery. It is an archive of the Earth’s atmosphere and the much-debated changes in the greenhouse effect.

Trapped in the ice sheet is the oldest record of the Earth’s climate, the fingerprints of the last ice ages, clues to reconstructing the way glaciers have moved down into Europe and North America eight times over the last million years, covering the northern part of the United States under hundreds of feet of ice and causing the oceans to drop precipitously before rising again amid the melting of the continental expanses of ice.

The National Science Foundation expects to invest some $20 million on the Greenland Ice Sheet Project, which is now in the second of four summers of drilling. It also plans to expand interest in high altitude mountain glaciers and to step up coring in the Antarctic, gathering samples of the air that actually enveloped the Earth in the ages past--molecules trapped in fluffy snow, then embedded in ice buried deeper and deeper with the passing centuries.

While the American and European drills are chewing through the Greenland summer, Soviet and French collaborators are preparing to resume work later this year on their second deep core in the companion Antarctic ice sheet, with hopes of capturing a record of climate going back half a million years.

Meanwhile, Lonnie Thompson, a scientist with Ohio State University’s Byrd Polar Research Institute, who recently sampled the Dunde ice sheet in central China, is off in Siberia gathering ice cores with a drill that is powered by the sun.

After hauling their equipment to the 17,000-foot peak of Dunde and drilling three 450-foot cores, Thompson and a Chinese colleague reported last year that temperatures on the Tibetan plateau have been warmer during the last 50 years than at any comparable period in 10,000 years.

As summer withdraws from Siberia, Thompson will move with it, ending 1990 high in the Peruvian Andes, continuing his investigation of regional climate behavior, while teams drilling the deep holes at the extreme latitudes work to decipher the great forces that shape the global system.

In these precious frozen cylinders of ice, scientists are acquiring priceless fossilized remnants of the ancient atmosphere.

Three years ago, a team led by Frenchman Claude Lorius produced compelling evidence linking carbon dioxide to global warming. Analyzing a core drilled by a Soviet team in Antarctica, French and Swiss scientists plotted a direct link between the Earth’s temperature and the carbon dioxide content of the atmosphere during 160,000 years.

Produced by the metabolic activity of animal life and the burning of fossil fuels, such as wood, coal and oil, carbon dioxide makes up only a small fraction of the atmosphere, but it is the principal gas that warms the Earth by preventing heat from the sun from being radiated back into the atmosphere.

From Lorius’ work on the 7,200-foot Vostok core, scientists now know that during the last Ice Age, which ended about 14,000 years ago, the carbon dioxide content of the atmosphere was less than two-thirds of its present level. The core shows that with the onset of the current interglacial period, carbon dioxide has been steadily escalating--most dramatically since the invention of the steam engine and the beginning of the industrial revolution and its massive consumption of fossil fuels.

From Ice Age levels of about 200 parts per million, the carbon dioxide content rose to 275 parts per million a century ago, and has since jumped to an historic high of nearly 350. The surge comes not only from the outpouring of carbon dioxide, but from the less-understood production of swamp gas and methane, and the use of potent chlorofluorocarbons, such as the Freon used in air-conditioning.

John A. Eddy, a scientist at the University Corporation of Atmospheric Research in Boulder, Colo., contends that the Vostok record “is the clearest evidence we have of nature speaking to us” on global warming. More than any other single piece of evidence, it has turned man’s potentially destructive influence on climate into a raging international political debate, fired interest in glaciology and atmospheric chemistry and focused more attention on Arctic research.

A larger message in the ancient ice, adds Wallace Broker of Columbia University’s Lamont-Doherty Geological Observatory, is that climate is susceptible to huge and relatively rapid changes never before suspected, and that the ocean-atmosphere system possesses the marvelous ability to somehow reorganize itself after a disruption.

The prevalent explanation of the advance and retreat of the ice ages and other equally immutable climate cycles is that they are driven by astronomical forces--a changing tilt of the Earth’s axis, rhythmic changes in the shape of Earth’s orbit around the sun and a periodic wobbling in the planet’s rotation.

The peaking of a new ice age every 100,000 years and the intervening periods of warmth, such as the one the Earth has now enjoyed for about 13,000 years, have come to be known as the Milankovitch cycle--for the Yugoslav scientist who developed the explanation in the 1920s and 1930s.

But Broker, who is regarded as one of America’s foremost figures in climate and ice core research, says the Milankovitch cycle “is no longer adequate” to explain what is revealed in the ice cores. “There are variables which are global, synchronous and fast. There are probably states of the system that we still haven’t seen. We have to consider that we may be giving (global warming) a push, that we could push it into a mode of operation that we know nothing about.”

Some climatologists believe that a dangerous “push” is already being applied with the massive production of carbon dioxide, but other climatologists remain to be convinced that the warming--including the six warmest years on record during the 1980s--is outside normal historical variations. Dealing with the question of what is happening now and what may happen in the future is the challenge before scientists constructing mathematical models of the atmosphere with super computers.

While the emerging ice core record is stunning in its clarity, the excursions away from the Milankovitch cycle and the restructuring of the global climactic order have compounded the stupendous task of projecting climate behavior.

Even now, professional journals eagerly await results from new cores, refrigerated warehouses are being expanded to accommodate the miles of material being accumulated, and project managers are routinely bombarded by a stream of ideas for new analyses that can be made, many of them while the material is still at the drilling site.

“The field is in its heyday,” says Paul Mayewski of the University of New Hampshire, the chief scientist on the Greenland Ice Sheet Project. “We are running as many analyses as we can right on-site, and each year that we’re here we’ll bring more instruments out. There is enormous interest in the core, and the best way we can get information out quickly is to get more of our work done while we are here.”

Greenland’s summit site was chosen because it is the most stable area of the glacier. In the course of the year, its movement, tracked by satellite, is measured in tens of centimeters, while some leading sections move as much as 4 miles per year.

The core sections now being pulled to the surface are handled with the kind of extraordinary care that was lavished on the rock samples from the moon 20 years ago, and the pampering will increase as drilling progresses because the material grows more valuable with depth. Far down in the glacier, the record is dramatically compressed, forcing those scientists who are studying the ice to conduct their research with less material. The disappearance of even a single section would amount to the loss of the record for centuries.

Removed from the core barrel of the drill, each section is stored in a refrigerator to “relax” or adjust to the dramatically decreased pressure for a few days.

After that, a conveyor in the “science trench” 15 feet below the surface moves it along to be sampled at work stations, where scientists await it with band saws, lasers, computers, electrodes and microscopes.

Tests of electrical conductivity fix the age of any core sample. The discovery of sulfates and dust particles reveals ancient volcanic eruptions, which provide benchmarks in further pinning down the age of core segments. Because different isotopes of oxygen and hydrogen are involved in the formation of water molecules, causing them to freeze at different temperatures, scientists in the trench can draw important conclusions about the seasons.

During the first weeks of the project, when the team was still camped in tents, the ice cores moving down the line quickly showed tell-tale traces of the Soviet Union’s Chernobyl nuclear accident of 1986, the eruption of Mt. St. Helens in 1984, and the great Dust Bowl of the 1930s.

With the drilling operation still shaking out its kinks, ice that was sparkling white snow on the surface during the summer of 1783 was recovered with ash traces from a great volcanic eruption at Laki, Iceland. Before the first season was over, material going back to the 12th Century was hauled up, revealing dozens more eruptions around the world, most of them dwarfing Mt. St. Helens.

Because Greenland is closer than Antarctica to other land masses, the record of volcanic activity across geologic time should be clearer here and help resolve whether outbreaks of enormous volcanic eruptions threw enough ash into the atmosphere to block out sunlight and cause climate cooling.

Once the samples for on-site studies have been taken, 75% of each core segment remains, and much of it will wind up in the hands of investigators who are interested in the trapped molecules of air. The sections are stored in a deep, covered pit, where there is no chance of even slight melting. Later in the summer, several tons of them will be flown to Schenectady, N. Y., by the New York Air National Guard. There, a refrigerated truck will wait to transfer the cores to a freezer repository--trailed by a backup vehicle ready in case of emergency.

Eventually, investigators will carve the cores into small pieces that will be put into vacuum chambers and crushed, releasing the trapped gases to be analyzed for carbon dioxide and methane.

It will be three to five years before scientists finally know how much the Greenland core adds to the record of Vostok and how the progression of the last two ice ages and interglacials has strayed from the rhythm of the Milankovitch cycle.

Compared to others who have trekked high into the Andes and the Himalayas in search of ice records, the scientists living on the Greenland ice cap enjoy relative luxury. The Big House, a structure on pilings at the center of the camp, is both a community center and dining hall, where hefty meals--reputed to be the best in Greenland--are served up by three cooks.

Even before the Greenland project’s managers installed warm, semi-permanent igloos and hot showers, veterans of ice hunts on other glaciers had continued a perverse tradition of building a golf course. Those who do not golf have cross-country skiing for diversion. At the European station, church pews have been carved out of the ice for Sunday services, and humorists have strung up a hammock between poles hammered into the ice. The only real contact with the outside world is a Teletype and radio link with Sondre Strom Air Base.

Officials of the Greenland Ice Sheet project are hoping to produce a climactic record of the Northern Hemisphere to match and go beyond that of the Vostok core in the Antarctic.

The core already recovered is now closing in on the last Ice Age, and when fully analyzed, “provide the first high resolution--or for that matter medium resolution--picture of the entire Holocene period,” Mayewski said.

If they successfully reach the bottom of the ice sheet, they will also accomplish a great leap beyond the historic Antarctic core, not only because the record will cover a full 200,000 years, but because it will be verified by the European core being drilled from the same structure in the glacier.

Because of the high clarity of their core, the Greenland drillers hope to move along toward resolving the fundamental questions of the global warming debate: What is the link between carbon dioxide and temperature? Is the rise in carbon dioxide the cause or the result of temperature warming?

Confronted by this magnificent conundrum, scientists anxiously await the core from a period called the Younger Dryas. About 12,000 years ago, when glaciers of the last ice age were retreating, the climate threw itself into reverse with renewed cooling and regrowth of the ice sheets. After about 1,000 years, warming suddenly resumed, turning the ice back into retreat and the climate back into harmony with the Milankovitch cycle.

Under the circumstances, there is inevitably a sense of competition between the American and European scientists. The U.S. drillers take pride in the fact that they are recovering a fat 5.2-inch wide core, compared to the 4-inch core of their neighbors. But the Danes, the Swiss and the French have made the landmark discoveries that have invigorated ice-core research, and America’s new high-tech drill developed by the Polar Ice Coring Office at the University of Alaska-Fairbanks borrowed heavily from a design used by the Danes in the 1970s.

Collaboration between the teams has nevertheless grown close. The entire British encampment moved over to the American site for a party one night--if the Arctic can be said to have a summer night--earlier this month. American and European researchers have made plans to publish joint papers on their work, and an agreement has been concluded providing that either the Americans or the British would share their ice in case either one of the projects fails.

After the drillers reached a depth of 600 feet last summer, they set a goal of hitting 3,000 feet before packing up and heading for home this September. But work has fallen behind schedule because of a spate of bad weather in the spring, when high winds brought whiteout conditions that stopped work on the camp.

Within days, the project will reach a crucial juncture, the first test of what some scientists involved in it considered a high risk strategy.

The new drill, developed with an eye toward further deep drilling in Antarctica, where it is colder than in Greenland, will for the first time go into the operational mode to be used for the remainder of the drilling through the ice sheet.

Some veterans of earlier ice-coring projects favored using a proven drill because the Greenland project represents the return of the United States to the frontier of deep ice-core research after a long stretch on the sidelines.

In the 1960s, the Army Corps of Engineers’ Cold Regions Research and Engineering Laboratory drilled through the ice sheet at Camp Century in Northern Greenland, and in the 1970s American and Danish scientists took advantage of supply flights to radar sites to move equipment into Greenland and drill a deep core.

But an effort to drill a deep core at Byrd Station in the Antarctic ended disastrously when the drill was lost. After that, the United States sat and watched while the Europeans took the lead in exploring the deep cores.

The big test will come when drillers begin pumping butyl acetate fluid into the drill hole for the first time to prevent it from freezing shut. The coming days will also show how well the system is able to handle the ice chips it creates as it works and how well it will handle the brittle zone between 1,200 and 3,000 feet, where the ice is prone to shatter.

If it works as advertised, it will reach the Younger Dryas next summer, bringing up longer core sections and reaching for the first of the two ice ages beneath it.