Cooool science on Antarctica: why do scientists flock to the coldest, windiest, loneliest place on Earth?

Way down south, at the bottom of the globe, researchers at the South Pole Station are feeling low. Whipping winds and freezing temperatures have taken a toll on the 20-year-old complex. The dome-shaped building is sinking into a thick layer of snow. Power outages, fuel leaks, and sewage spills torment the 100 or more American scientists who live there during the "warmer" months.

Many of the researchers would like to replace their aging station with a $220-million high-tech structure. But some members of Congress want to cut back on Antarctic research. Why, they ask, should taxpayers spend so much money on such a remote continent?

Scientists have an answer: Because of its extreme conditions, Antarctica yields clues to our planet's past, present, and future. Right now, about 650 American researchers are flocking to Antarctica, as they do every September, to take advantage of the "balmy" spring and summer (-16 [degrees] C, or 4 [degrees] F, on a good day). After reading about some of their most interesting projects, ask yourself whether science in Antarctica is worth funding.

METEORITE MANIA

Other than natural-history museums, Antarctica is the best place to hunt for meteorites, or space rocks that crash into Earth. Last year, geologist Ralph Harvey and his team from ANSMET (the Antarctic Search for Meteorites) found 390 meteorites.

"If you want to pick up things that fall to Earth, the obvious thing to do is lay out the biggest possible white sheet you can find," says Harvey, a professor at Case Western Reserve University in Cleveland, Ohio. That's what Antarctica is -- a sheet of white-and-blue ice and snow the size of the United States and Mexico combined.

Meteorites peppering the surface of Antarctica are first covered by layers of snow. Packed in under pressure, the snow turns to ice. Over thousands of years, the ice spreads out toward the edges of the continent and usually breaks off as icebergs. Many meteorites encased in those icebergs float away, never to be seen again.

But some of Antarctica's mountain ranges (like the Transantarctic Mountains, see map) block the flow of ice toward the sea. Dry air and winds of up to 144 kph (90 mph) turn the trapped ice into vapor -- a process called sublimation. As the ice disappears, meteorites show up on the surface like chocolate chips in a cookie, just waiting to be scooped up by the ANSMET team.

Although Congress might find Antarctic research expensive, hunting for meteorites in Antarctica is the cheapest and safest way to collect specimens from our solar system -- without heading to space. But Harvey and other meteorite hunters have only six to eight weeks a year to search. Even during Antarctica's summer, sudden blizzards slow researchers down.

Now scientists are planning to send a "meteorobot" to Antarctica to help in the search. Scheduled for operation in 1998, the all-weather robot will be equipped with sensors to detect the chemical and magnetic signatures of meteorites. When it spots a possible meteorite, the robot will plant a flag in the ice so researchers know where to look.

BURIED LAKE

While some scientists explore the surface of Antarctica, others are learning more about a giant body of water 4 km (2.5 miles) beneath the ice pack.

Scientists first discovered Lake Vostok in the 1970s by using radio waves that penetrate the ice. Since then they have used sound waves and even satellites to map this massive body of water (14,000 sq. km, or 5,400 square miles).

How does the water in Lake Vostok remain liquid beneath an ice sheet? The thick glacier above acts like an insulating blanket and keeps the water from freezing, says Martin Siegert, a glaciologist from the University of Wales in Great Britain. In addition, geothermal heat from deep within the Earth may warm the hidden lake.

The scientists suspect that microbes may be living in Lake Vostok, closed off from the outside world for more than 2 million years. Anything found there will be totally alien to what's on the surface of Earth, says Siegert. Scientists are trying to find a way to drill into the ice and draw water samples without causing contamination. Again, robots might be the solution.

If all goes as planned, a drill-shaped cryorobot (cryo means cold) will melt through the surface ice. When it reaches the lake, it will release a hydrorobot (hydro means water) that can swim in the lake, take pictures, and look for signs of life.

The scientists hope their discoveries will shed light on life in outer space, which might exist in similar dark and airless conditions. Recently, close-up pictures of Jupiter's moon Europa showed signs of water beneath its icy surface. Once tested in Antarctica, cryorobots could be sent to Europa to search for life there, too.

PENGUIN PLUNGE

Meanwhile, a scientist at Montana State University has discovered that penguins in Antarctica are taking a plunge. In the mid-1980s, zoologist Wayne Trivelpiece found that 22 of every 100 Adelie penguins returned to their nesting grounds on King George Island to breed. Last year, he recorded only 10 of every 100 hatchlings returning -- more than a 50 percent drop.

Why the decline? Trivelpiece suspects warmer weather. Winter temperatures on the island have risen 5.5[degrees]C (9.9[degrees]F) since the 1940s. The heat isn't frying the birds, but it does melt sea ice. As the ice disappears, so do algae that cling to it. Without algae to feed on, shrimplike creatures called krill die too. And krill are the mainstay of the penguins' diet.

Some scientists say warmer winters are natural -- just a blip in the climate record. But Trivelpiece and others worry that the trend is a sign of global warming, a rise in Earth's temperature. Global warming may result from human activities such as burning fossil fuels (coal and oil) and cutting down rain forests. These actions release gases like carbon dioxide and methane into the atmosphere. The gases trap the Sun's heat and drive up temperatures.

Other scientists fear that global warming could melt an ice sheet in West Antarctica, releasing enough water to raise the world's oceans 6.25 meters (20 feet) or more and flood coastlines along Florida and elsewhere.

Seasonal Flip-Flops

It's fall in North America, but spring in Antarctica. Why are seasons opposite in the Northern and Southern hemispheres? To find out, do this experiment.

WHAT YOU NEED

a globe * a flashlight * a dark room * a partner

WHAT TO DO

1. You be the Sun (hold the flashlight). Have your friend be Earth (hold the globe). Your friend should stand about 1-1.5 m (3-5 ft) away from you.

2. To model an Antarctic winter, position the globe so that the Southern Hemisphere is tilted away from the Sun at an angle of 23.5 [degrees] (about one quarter of a 90 [degrees] right angle, see diagram).

3. Aim the light directly at the center of the globe. The light will be shining on the Tropic of Cancer, 23.5 [degrees] N latitude.

4. Spin the globe to see the concentration of light on different parts of Earth.

CONCLUSIONS

During the winter, does Antarctica receive more or less direct sunlight than North America? Try to model summer in Antarctica. Have your partner move counterclockwise (like the orbit of Earth around the Sun) halfway around you. Keep the Earth's tilt the same (23.5 [degrees]). Which continent gets more light now?