Before the Ice Melts
By Kevin Rayburn
Glaciologists race to 'read' history locked in disappearing glaciers
The skin on your face is burning off. The sun's UV rays are scorching you, but you are freezing. Caught 20,000 feet up a mountain in China or Peru, you have nothing but a compass to guide you back to base camp 15 miles away through a blinding blizzard. You have been close to avalanches—too close. You have jury-rigged solar panels to run your equipment because fuel is too heavy and dangerous to carry. It would freeze in the motor anyway. You are slimed with sunscreen as thick as axle grease. You haven't bathed in months. You are wet, cold, exhausted and hungry.
This would be you, if you were on an expedition with Keith Mountain.
But Mountain, chair of the Depart-ment of Geography and Geosciences in UofL's College of Arts and Sciences, says the hardships are worth it. It might help save the planet.
Once or twice a year he and colleagues from the Byrd Polar Research Center at Ohio State University travel to a high glacier in mountainous areas of Bolivia, Peru, China, Antarctica or Tanzania where they spend months hunting for a disappearing treasure: ice.
Glacier ice contains thousands of years of the Earth's climate history. It also provides clues as to how and why global warming is happening today, Mountain says.
Ironically, the quickly melting ice due to global warming is causing those precious climate records to be erased forever. For Mountain and colleagues, it's a race against time to document these disappearing natural records.
The researchers use a portable drilling system they perfected through two decades of glacier exploration to extract from the glaciers cylindrical ice cores about 13 centimeters in diameter and hundreds of meters long. Each is cut into 1-meter segments, then marked and packed for later analyses.
"If we go down, say, 450 meters (1,476 feet), that means we're bringing out 450 boxes of ice core, and that's very heavy," Mountain says.
Like the rings of trees, ice cores are time capsules for scientists.
"We can reconstruct atmospheric temperatures and ascertain precipitation rates and how much dust there was in the atmosphere," Mountain says. "We can find out the chemical composition of the atmosphere. You can pick up things like various nitrates—sea salt, for example—and figure out wind directions and the sources of moisture and how those may have changed over time."
Ice cores can span tens of thousands of years. A team of Russian scientists in Antarctica recently obtained ice cores dating back more than 160,000 years.
A major logistical operation
It takes a half a million dollars to mount an expedition by a handful of scientists to a remote glacier and fly in the tons of equipment and supplies they need, Mountain says.
After selecting a site for study from a previous reconnaissance, the researchers make their way to the base camp with help from hired local guides via truck and pack animals. All plans are pre-approved and logistical needs worked out with government officials in the destination country.
In Tibet, for instance, the researchers contracted with local herdsmen to carry the specially packed ice cores down from a mountain on the backs of yaks. Refrigerators in nearby towns had been rented in advance for storing the cores until they could be transported back to the United States.
"It's expensive and cumbersome to get 3 tons of ice core out of places like China or Peru," Mountain says. "And you have to make sure they stay cold the whole time."
Keeping the load of supplies to the bare minimum also is essential.
"One of our team's claims to fame is that we've made portable, lightweight drilling and ice-core recovery a commonplace practice in our field of research," Mountain says.
Equipment breakdowns due to severe weather require the researchers to be impromptu handymen. Running the ice-core drill on solar power is one example of their ingenuity.
Mountain says he became mechanically inclined as a boy growing up in the Australian Outback.
"I was a farmhand in the backwash of Australia, in Central New South Wales. I fixed tractors and farm equipment and so on."
After his auto mechanic father moved the family to be near his new job working on the hydraulic systems of a hydroelectric dam, Mountain developed a fascination with Antarctica and, later, environmental education.
Mountain earned a degree at Melbourne University and then got into geology and geography at the University of Oregon. A research trip to a glacier in Oregon's Cascade Mountains determined his life's work.
"I found glaciers to be such a remarkable natural phenomenon," he says. "I wanted to figure out the mechanics and physics of how they worked."
In the last 20 years, Mountain's interests broadened to include global climate relationships: specifically, what glaciers in different parts of the world can reveal about both local and worldwide climatic conditions.
The ice-core studies have deepened that understanding.
"We have learned more in the last 10 years from these projects than we have previously," Mountain says, "because we are better able to get the frozen cores out of the sites and because the technology for analyzing the cores is faster and more comprehensive."
An alarming retreat
The title of Ernest Hemingway's short story "The Snows of Kilimanjaro" is fast becoming a historical curiosity. That's because, like many glaciers worldwide, the white cap of Mt. Kilimanjaro in Tanzania will soon be no more.
"Those glaciers are in an extraordinary state of retreat," says Mountain, who along with his colleagues from Ohio State recovered ice cores from Mt. Kilimanjaro in 2000 and 2002. "We figure that at the current rate of melting, the ice will disappear on Kilimanjaro by about 2015."
Rising temperatures worldwide as well as local decreases in precipitation are contributing to the decline of the glaciers.
Mountain and his colleagues see this "retreat" happening at many of the glaciers they're studying.
"When I started out in this field in the late '70s I never would have thought that the photographs we took of this big ice sheet in southern Peru would become archival records of something lost," he says. "We photograph the changes there every year now, and the changes are occurring quickly. It's retreating on the order of 50 meters a year."
For the past 25 years, Mountain has worked with a core team from Ohio State—a team that includes Lonnie Thompson, who was mentioned in Al Gore's Oscar-winning documentary An Inconvenient Truth. Their work has disproved conventional wisdom that glaciers on mountains in tropical latitudes could not yield a reliable climate record.
"That's because of all the moving and melting that these glaciers do and the accumulation of rainfall. They are kind of like moving targets."
Through mathematical models and other methods, including preliminary test drillings, the team can determine the amount of ice compression and come up with reliable ways to interpret these ice cores, he says.
"So we definitely proved that an interpretable long-term record could be had from these glaciers, going back thousands of years."
Another unanswered question that team tackled was whether glaciers could show that climate changes were more localized or global in scope.
"We were able to determine from interpreting the ice records that, yes, climate change is global and real."
The human fallout
Mountain says glaciologists are just one sector contributing to the mass of evidence on the reality of global climate change.
"Interpreting this thing called global climate change is not isolated to any one scientific area. It's an enormous preponderance of evidence that comes from scientific disciplines across the board."
Some skeptics might disagree, but Mountain points to row after row of scientific books and reports in his office that both verify global climate change as well as show the human activities such as pollution that are hastening global warming.
"Instead of people saying they don't believe it's happening, they have to refute it with facts. They are going to have to prove all these books wrong."
Mountain says that 95 percent of the scientific community believes that global climate change is happening and that humans are a significant causal factor. Yet somehow, he adds, a 95 to 5 percent ratio becomes a yes-no, either-or vote.
"Some are trying to turn this into a debate, but there is no debate," he contends. "I guarantee you that if all these people who doubt global warming had a 95 percent chance of winning the Kentucky Lottery, they'd run down to the Pic Pac and buy a handful of tickets. Yet when it comes to this issue, 95 percent somehow becomes 'uncertainty.' "
Whatever the case, Mountain says the important question is: What are we going to do about it?
Mountain recently returned from a family visit to Australia where he says the people are really concerned about climate change. After prolonged years of drought and fighting bush fires and watching their cattle die, global warming has become a real issue. That's true in other parts of the world as well, he says.
"For the people in Peru, as the glaciers melt they are losing their irrigation water for farming. In Tibet as the glaciers recede streams are evaporating and leaving big salt deposits that make the remaining water undrinkable.
"But here in Kentucky we have plenty of water and aren't suffering yet, so we think that nothing is wrong."
The jury is no longer out on global warming, Mountain says.
"At some point, the jury has to come back and make a decision. What kind of policies are we going to develop to deal with this?"