National Science and Technology Week, April 26-May 2, 1998Polar Connections
"P O L A R   C O N N E C T I O N S"
A National Science Foundation Initiative for National Science & Technology Week

Curiosity and Concern -- Exploring the World's Natural Laboratories

By Sean J. Kearns

In some places on this driest of continents in terms of annual precipitation, the ice sheet is three miles thick. Underneath it are active volcanos and lakes of liquid fresh water.

Thus, while cultures and societies shaped the Arctic from its fringes for millennia, Antarctica remained unseen by humans until less than 200 years ago.

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Coast Guard icebreaker opens the
annual cargo ship channel to
McMurdo Station, Antarctica.

How can we be in a desert if 70% of the world's freshwater is here? Welcome to Antarctica.

How can we be on an ocean if that bear is coming at us? Welcome to the Arctic.

Though connected by meridians that converge at each pole, the last, vast frontiers of the polar regions are dissimilar in many ways. The Arctic, after all, is an ocean surrounded by land, while Antarctica is vice versa. As an Arctic scientist put it, "We've got the pond. They've got the island." Oddly enough, the pond has polar bears, and the island has penguins.

To emphasize the scientific importance these regions hold, from basic curiosity to global concern, the National Science Foundation (NSF) selected "Polar Connections, Exploring the World's Natural Laboratories" as the theme for National Science & Technology Week, April 26 to May 2, 1998.

The theme underscores NSF's role in funding about 500 research projects annually in the Arctic and in Antarctica. NSF manages the U.S. Antarctic Program, and it leads the efforts to coordinate science activities of 12 federal agencies in the Arctic.

Long ago, humans reached the northern realm and, about 10,000 years ago, crossed the Bering Sea land bridge to people the Americas. In the South, 25 million years before humans evolved, the last land bridge to Antarctica disappeared as the continent broke away from the ancient southern supercontinent of Gondwana, a separation that left it isolated by its circumpolar ocean. Thus while cultures and societies shaped the Arctic from its fringes for millennia, Antarctica remained unseen by humans until less than 200 years ago.

Today Antarctica is a platform for exploring the deep ocean forces behind El Niño and the atmospheric causes for ozone depletion. It provides an earthly porthole to the heavens that is unparalleled in its clarity.

The Arctic is a wellspring of winter storms that batter the U.S. and Canada and, in a weird reciprocation, acts as a collecting pool for pollutants that make their way north from temperate latitudes.

Something about the polar regions rearranges one's perspectives, bends them, reflects them, sometimes breaks them -- generally clearing the stage for bold new discoveries. It's called ice.

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Old house site, Russian Arctic

More than 98% of Antarctica is covered with a massive sheet of it. At the South Pole, where the temperature averages -58o F, the ice rises 9,200 ft. above the bedrock. In some places on this driest of continents in terms of annual precipitation, the sheet is 3 miles thick. Underneath the ice are active volcanos and lakes of liquid freshwater. On its surface, hundreds of millions of birds congregate near the sea edge, while, across the interior, thousands of meteorites have been scattered like pepper. And if you look deeply into it (with the right technology, of course), visions appear of sub-atomic particles that have traveled from the far reaches of space -- and through the Earth.

In the Arctic Ocean, the sea ice seldom exceeds 6 ft. thick. But breaking through from underneath it can be tricky, even for a U.S. Navy attack submarine. In 1995, the sub that carried the first civilian science mission under the Arctic was able to surface near the North Pole, where the ice was 3 ft. thick. For most of the ship's attempts to surface, however, the ice was either too thick to penetrate safely or too thin to hold up equipment. Twice when camps were set on the ice, visiting polar bears cut short the scientific agenda. The cruise, zigzagging 10,800 nautical miles under the ice, still collected enough data to answer questions about chemistry, currents and the continental shelf -- and to chart an undersea plateau that rises nearly 10,000 ft. from the depths.

From both regions come samples of buried ice. Extracted by drills reaching more than 10,000 ft. deep into ice sheets on Greenland and Antarctica, these ice cores yield a chronology of climate dating back hundreds of thousands of years.

Every year, the expanding and shrinking realm of floating sea ice affects the global weather. Acting as a variable lid on the polar oceans, it reflects the sun's energy rather than allowing it to be absorbed by the dark ocean. The ice cover also prevents the release of the ocean's heat energy upward to the atmosphere. Such interactions are surveyed by SHEBA, the Surface Heat Budget of the Arctic Ocean project. As part of this, the largest and most complex science experiment ever supported by NSF in the Arctic, a research vessel was left in October 1997 to drift, frozen in the Arctic Ocean for 13 months.

The poles also serve as drop-offs for data from the rest of the world. In polar orbits about 500 miles over the earth, remote-sensing satellites follow meridians from pole to pole 15 times a day, gathering images of the globe as it spins. Thus, after making a swing over a new swath of the globe, the satellites return above the polar realm, where their data can be transmitted to a single station.

"So," as a geophysicist puts it, "if you want to look at the whole earth every day, you do it from a polar orbit."

Northern Lights and Meteorites

When you look upon a star, it makes a difference where you are.

If your heart's desire is to look higher, go where the sky is cold, clear, dark and dry. Go to a place like Poker Flat, a research range 30 miles northeast of Fairbanks, Alaska. Where a century ago prospectors sought gold dust, scientists today explore the secrets of the aurora borealis.

One dark and geomagnetically stormy night, these northern lights danced for poet Robert Service: "It swept the sky like a giant scythe, it quivered back to a wedge;/ Argently bright, it cleft the night with a wavy golden edge."

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Aurora Borealis in Alaska

Now we know that the swirling glow occurs when electrically charged particles of the solar winds are drawn toward the earth's poles by electromagnetic fields. When the particles reach the upper fringes of the atmosphere, they excite nitrogen, oxygen and other gases there, simultaneously creating crowns of color that cascade above each pole. They may reign in the sky from 50 to 600 miles above Earth, in crimson, blue and green. On the space shuttle, as it cut through the northern crown about 190 miles up, an astronaut described the aurora as "forests of columns of light."

As auroral understanding has increased, so has the ability to predict the phenomenon's range and intensity a few days ahead, and not just for stargazers. Many others need to know when a geomagnetic storm is brewing because a strong aurora can disable power grids (especially in Canada), knock out satellites, disorient homing pigeons, tweak navigation instruments and corrode the Alaska pipeline by inducing a current that commonly reaches 1,000 amperes. Its southern sister, aurora australis, has fewer viewers but is just as spectacular. The two auroras often project near-mirror images.

Antarctica, particularly at the South Pole, presents special challenges and charms for those who seek to learn the sky's secrets. At the pole, for example, with severe cold and near absence of water vapor, the infrared skies are consistently clearer, cleaner and darker than anywhere else on the Earth. Indeed, less than a mile from the main building at Amundsen-Scott South Pole Station sits an observatory in a region called "the dark sector" because light and radio waves and other electromagnetic noises are minimized.

Curiously, one of the most intriguing ice-dependent studies of the heavens is focused downward. Lying on the ice are specimens from space that take just an eye to spot and a hand to grasp: meteorites. Says Ralph Harvey, leader of the U.S. search for meteorites in Antarctica: "Most of the time we go to places where any rock we find on the ice had to fall there from the sky." Antarctica, he adds, offers a vast landing field, relatively barren and undisturbed, "a unique collection site to pick up pieces of the universe."

Last season, NSF's Antarctic Search for Meteorites program picked up about 1,100 extraterrestrial rocks, bringing its 20-year total to about 9,000. (European and Japanese efforts have gathered an additional 7,000 from the ice.) Most, says Harvey, are "ordinary chondrites," almost certainly hailing from the asteroid belt, "a region of space where Jupiter and the sun play a tug-of-war and throw rocks around." Rocks from Mars and the moon are rare exceptions, amounting to about two dozen from among the world's collection of 20,000 meteorites.

"They get most of the attention. That's how science is," he says, philosophically.

The proof of Martian origin came from a tiny bubble of atmosphere locked in the glass of a once-melted rock. The ratio of gases within -- including argon, krypton, xenon, radon, nitrogen and carbon dioxide -- matches perfectly what the Viking lander told us about the atmosphere of Mars.

"Antarctica," says Harvey, "is nature boiled down to rock, ice and sky. It offers us a great base line on almost any scientific endeavor you may undertake ... That's what keeps me going: I'm standing in a simple place looking at a place more complex."

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Adélie Rookery, Torgersen Island, Antarctica

Diving and Dining

"Almost everything about emperors is impressive." Gerald Kooyman is talking about penguins. A biologist at Scripps Institution of Oceanography, Kooyman for years has left San Diego for Antarctica to monitor the emperors' lives.

After breeding in the winter, the males "face the polar night head on," he says. They huddle on the ice, each holding on his feet a single egg blanketed for incubation under a fold of the abdomen. "There are 9,600 species of birds," says Kooyman, "and there's only one adapted for year-round high-polar living."

To endure the harsh, wind-driven cold, the males stick tightly together, reshuffling their huddle, with birds taking turns on the perimeter to cut individual heat loss by half. With feathers under their toes and insulative pads on the back of their feet, they can rock back "when it really gets cold," Kooyman says. "Thus they have very little contact with the ice." With a highly insulative cover of feathers and limited surface area for body size, emperors retain heat extremely well. "But that's at a cost," says Kooyman. "They're not very mobile."

Except in the water. Emperors can generally dive down to 320 ft. for about 10 min. at a time. However, in one dive out of 200 to 400, they go down more than 1,600 ft.; after -- or away from -- what, Kooyman isn't sure. In these same seas, Weddell seals can descend to 2,300 ft. for as long as 82 min. How do these divers do it? According to Kooyman, "The answer comes down to oxygen." Pound for pound, Weddell seals can store more than four times as much oxygen as humans can; emperors more than double. The trick is not holding their breath -- indeed, the seals' lungs collapse by design at depths -- but in storing oxygen in myoglobin, an iron-rich, oxygen-binding protein.

Studies of the prolonged, deep diving of seals may help us understand how organs survive low blood flow and oxygen depletion, possibly leading to new treatments for shock, stroke and transplant patients; and research into the ways oxygen-rich blood and other means allow seals to stop breathing may yield insights into Sudden Infant Death Syndrome.

While the seal and the emperor dive to dine, feeding on the fauna of the southern ocean, musk-oxen and caribou feed on the flora of the terrestrial far north. That's where Robert White and Brad Griffith find them.

As a fog lifted off the tundra, White, director of the Institute for Arctic Biology at the University of Alaska at Fairbanks, once found himself surrounded by a hundred newborn caribou calves. Bleating their distinctive "Ott, ott, ott, ott," the calves instinctively go to the largest image on the horizon -- in this case, White. "Obviously, the guys aren't very discriminating," he says.

Griffith, a biologist with the institute's Large Animal Research Station, has found himself on the skids of a helicopter, poised to "net-gun" an adult caribou out of a herd running below. "They look like greyhounds with boxing gloves on their feet," he says. With the kickback of each step, a concave hoof launches a large snowball, leaving Griffith to duck and bob on the fly.

Though at first glance the big, brown, horned herbivores seem similar, musk-oxen and caribou rely on different tapestries of adaptations to survive. The weaves begin with the grasses they choose.

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Glacier and Royal Society Range, Antarctica

Caribou select the choicer vegetative cuts, such as lichens, which they can smell through the snow. It's like "taking the good stuff" out of trail mix, says Griffith. For a herd of 100,000 to feed, it has to keep moving; and the larger the herd, the faster it moves. Some herds zigzag as much as 1,680 miles a year. With every step of the animals' long legs, their extremely elastic tendons recapture energy, says White, who awards caribou the "world record for most efficient walking." With long, hollow hairs and a fine layer of underwool, caribou are well insulated, he says, "and when they swim rivers -- we're talking serious water -- they're very buoyant." The ability to lift their hairs, called piloerection, allows the caribou to release heat after exertion. Thus without overheating, they can choose flight over fight when approached by a predator.

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Sea ice, Choris Peninsula, Alaska

Musk-oxen have wide mouths that can mow a valley floor down to its woody stems and stomachs to digest poor-quality grasses and sage. "They tend to locate in valleys and exploit them intensively," says White. "Only the immature males wander away."

In some ways, their survival strategies resemble the emperors'. They have extreme insulation (provided by long guard hairs that create a thick shaggy wool called qiviut) and short legs to reduce surface area -- and both traits reduce mobility. But they don't dive, and there's the qiviut caveat: "Musk-oxen have a real problem dumping a heat load," says Griffith. "They just don't ever run from a predator; they use their horns for defense. So wolves will try to run musk-oxen until they get a heat load."

Their reward could be a warm dinner.

The Haze and The Hole

When it comes to polar pollution, what goes around, comes around ... and stays around.

Carried by patterns of atmosphere, seasons, metabolism, oceans and animal migrations, effluent of industrial society can find its way to the seemingly pristine Arctic. Persistent organic pollutants move up the food chain. Pesticides move north from as far south as India. Mercury in humans in the Arctic is 5 to 12 times as high as in more southerly populations. Radionuclides there hail from decades-old testing of nuclear bombs, the 1986 accident at Chernobyl, and releases from European nuclear processing plants.

While the Arctic faces increasing environmental threats, Antarctica begins an era of unprecedented protection. In January 1998, the Environmental Protection Protocol to the Antarctic Treaty took effect, proclaiming the continent to be a natural reserve devoted to peace and science. It bans mining and mineral exploration for at least 50 years. It requires nations with scientific operations there to remove garbage and reclaim old dumps. It prohibits pesticides, polystyrene packaging and pets, including dogs.


Research Balloon Launch, Antarctica

Globally, polar science has diagnosed two environmental ills of atmospheric proportions: the ozone hole and Arctic haze. Both are attributed to society's discharge contacting the harsh cold of higher latitudes. Both diagnoses met skepticism, but after hundreds of scientific second opinions, the hole and the haze are recognized as serious threats to the planet's health. Their annual onsets, however, are as different as north and south.

With a fabric of oxygen atoms bound together three at a time, the ozone layer serves as a stratospheric security blanket, protecting the earth from ultraviolet rays. Each spring over Antarctica, as the layer thins, more UV hits the earth -- particularly wavelengths known as UV-B, as in "bad." When scientists realized that from 1975 to 1985 stratospheric ozone levels fell 40%, creating a "hole," they warned the world. Like moths among wool, something eats away at the blanket. Decades of research identified chlorofluorocarbons (CFCs) as the main cause of damage. Used as aerosol propellants and refrigerants, as well as to produce plastic foam, these gases eventually rise to the stratosphere, where intense UV dismantles them, releasing their chlorine, which then breaks up the molecular oxygen trios.

While some researchers use balloons, satellites, lidar and other means to peek at the chemical pathways of the stratosphere, others focus on the impact of increased UV on marine ecosystems. There it appears to reduce phytoplankton production -- crimping the beginning of the food chain -- and to damage icefish DNA.

Ozone above the Arctic, though declining, remains intact partly because the stratosphere there is warming all winter. Far below, less than 3 miles above the earth, coldness contributes not to depletion, but accumulation -- of a seasonal smog called Arctic haze. "The largest pollution pool known on planet Earth," according to Glenn Shaw, one of the first geophysicists to investigate its origins. The degree of pollution, he says, "is comparable to an Ohio countryside, but not to Cleveland."

The Arctic air becomes stagnant during winter because there is little solar radiation to mix it, Shaw explains. As winter progresses, it becomes colder, more stable, and expands from just above the pole to become "an air mass the size of Africa, massively and homogeneously polluted with aerosols, trace gases, lead, cadmium, sulfates ... a kind of witches' brew of industrial pollution," says Shaw. Then he peers out his window to catch a mirage of mountains levitating in blue sky, an image crafted by light's refraction through the crisp cold layers above Fairbanks, Alaska.

Watching a red, squashed sunset in Alaska about 20 years ago, it dawned on Shaw: "Whatever it was [in the haze], it was very small particles ... and it was coming from a long way away." It has since been traced to the smokestacks, exhaust pipes and other outlets across North America and Eurasia. On rare occasions, it holds dust from the Gobi Desert.


Geographic South Pole

Each summer, as the air warms, the haze, like a mirage, abruptly disappears, only to reform the next winter. "Where does it go? It's an unsolved mystery," says Shaw. Over the past decade, it has not grown substantially, but toxins and trace metals are found increasingly concentrated in the Arctic soil, oceans and biological tissues.

Shaw adheres to the theory of a "fractional distillation machine." As the volatile compounds from warmer industrialized regions reach the atmosphere, they may tend to stay there until they migrate to a colder region, where they condense and descend. As seasons and temperatures change, the cycle may repeat itself continually, ultimately stratifying the pollutants by latitude, according to the specific coldness that each pollutant needs to condense.

"Easy to say, hard to quantify," according to Shaw, but "in the end [each year] the Arctic haze contamination is removed and enters more 'permanent' media [in the Arctic]."

From beneath sea ice to beyond the stratosphere, polar science continues to uncover clues to how our planet works. By going to these ends of Earth, we increase our understanding of global changes and extend our vision to the far reaches of the universe. We learn more about how Earth's coldest regions are connected -- to each other, to the rest of the world and to us.

Science writer Sean J. Kearns (a public affairs officer at California's Humboldt State University) has visited the Arctic and the Antarctic. The University of Alaska Fairbanks deserves special acknowledgment for its assistance in preparing this supplement.

This advertising supplement is sponsored solely by participating advertisers. NSF does not in any way endorse or recommend the sponsors in the advertorial or any particular product of that sponsor. The text was prepared by Sean J. Kearns and did not involve the reporting or editing staff of Discover or TIME.

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