Local researchers look for future in our icy past

At the bottom of the world, at the bottom of the ocean, through ice a football field deep and a half-mile of rock, scientists have been taking the Earth's temperature.

Like a thermometer stuck into the planet's backside, a drill probes Earth's past.

The results of the drilling -- akin to a temperature chart on a hospital patient's bed -- will help gauge the future health of the planet.

Two researchers from Northern Illinois University in DeKalb -- Ross Powell and Reed Scherer -- are leading an international effort to study the climate of Antarctica.

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According to their literally groundbreaking work, the Antarctic hasn't always been frozen over, and it won't stay that way in the future.

The goal now is to better pinpoint how fast global warming may occur and what may be the consequences.

The story of temperature change is one told by millions of microscopic fossils, the decaying carcasses of faithful sled dogs and a robot going where no man has gone before.

And it's a tale set in a land of blinding white plains, towering icebergs the size of high-rise buildings and an active volcano coughing dusty plumes against a sky that in summer never goes dark.

"Every time you get off the plane and look around, you think 'Wow, it's great to be back again,'" Powell said. "This is a spectacular place to be."

Natural cycles?

Don't sweat it: The Earth has been much warmer in the past than it is now.

Amid dire warnings of global warming, it seems comforting to know that the planet has survived past cycles of warmth and cold, driven in part by changes in the Earth's orbit. Antarctica itself was once home to dinosaurs basking in a semi-tropical climate.

But past climate change often took place over eons, and involved nasty side effects including the extinction of thousands of species of plants and animals.

In recent years, the burning of fossil fuels worldwide has increased carbon in the atmosphere at a rate far exceeding the historical record.

The Intergovernmental Panel on Climate Change predicts world temperatures could rise 2 to 11 degrees Fahrenheit by the end of the century, melting parts of the polar ice caps.

Such melting has apparently begun, with the Larsen B Ice Shelf, a chunk of ice the size of Rhode Island, breaking up in 2002.

Antarctica is a continent larger than the continental United States and Mexico, covered with ice more than two miles thick. Complex computer models are used to attempt to predict climate change. By figuring out how fast Antarctic ice shelves have melted in the past, Powell and Scherer are trying to give climatologists reliable data for their models.

To further that goal, both men came to NIU to work at its Analytical Center for Climate and Environmental Change, which has made DeKalb an unlikely center of polar research.

Both live in Elburn with their families, but typically leave for a few months in the winter to do research in Antarctica's summer, when temperatures hover around freezing.

After living in tents in the early years of their work, they now stay in buildings with dorms and hot meals, though survival training is still necessary in case a storm catches anyone outside.

Last winter, both men worked on a project, dubbed ANDRILL, that drilled deeper than ever before into the bedrock below the Ross Ice Shelf, a sheet of ice hundreds of feet thick covering an area the size of France.

The diamond-tipped, hot-water drill pulled up a half-mile core of muddy-looking sediment that looks like it might have come from a creek bed.

But the core is filled with diatoms, one-celled creatures that look like fluff when held in the hand. Under the microscope, however, they morph into something resembling beautiful, blue-and-green blown glass.

By counting the concentration of diatoms at different levels, Scherer's team can judge when the ice shelf was frozen over, and when it was melted away leaving an open ocean.

By their count, the ice shelf has frozen and thawed more than 60 times over the past 14 million years.

Preliminary analysis suggests the ice shelf must have had a significant impact on global sea levels and currents.

More recently, Scherer saw his own evidence of global warming near McMurdo Bay. There remains a building used by Antarctic explorer Robert Scott and his men, who died on an expedition to the South Pole in 1912.

A subsequent expedition by Ernest Shackleton left behind dead sled dogs, whose frozen bodies remained with no signs of decomposition when Scherer first saw them in 1986. By last year, however, the bodies were black with mold, an anecdotal but morbid example of the recent warming of the Antarctic.

A special place

This fall, the ANDRILL project continued, with a second team of researchers conducting drilling at another site going back 17 million years into the geologic record.

Meanwhile, Powell returned to the ice shelf to look for his next drilling site.

Every time he returns to Antarctica, he is struck by its expanse of ice sheets and sky, unbroken planes of white, blue and gray, with no sound except from the wind and the people he is with.

Sometimes, they have company. Adelie and Emperor penguins will see the researchers from far away, and waddle or slide up on their bellies to see what they're up to. The penguins might watch for a couple of hours before squawking to each other and going on their way.

"The Antarctic is such a unique and special place," Powell said. "It's the magnitude of the place and the sense of isolation, just how big and powerful it is and how small that makes you feel. Everybody who goes feels privileged to be there."

Powell's next project, he hopes, will take a more detailed look at the relatively recent past of this wintry wilderness.

The past 10,000 years, he hopes, will provide a good barometer of climate change since the last Ice Age -- a scale more comparable to the rapid changes the planet may be facing.

At the same time, because it takes years to plan and fund such projects, he's developing a robot submarine, which could be dropped through a hole in the ice to explore the previously unseen bottom of the Ross Ice Shelf.

That way, Powell could test the temperature and saltiness of the water to determine how fast the ice shelf is melting.

Also this year, at age 50, Scherer won a Fulbright Scholarship to work on climate change. He will compare the temperature variations in the Antarctic with geological formations that reflect temperature swings in New Zealand, in an effort to judge the effect of Antarctic conditions on worldwide climate.

On the ANDRILL Web site, he wrote a short and silly poem which does a fair job summarizing his line of work:

"A paleontologist, me. I seek tiny fossils, you see. Warm climates of past, How long did they last? My bugs hint at what futures may be."