In 1990, when climatologist Konrad Steffen established Swiss Camp, one of the first automatic weather stations on Greenland’s ice sheet, global warming wasn’t high on his agenda. Steffen wanted to study the interaction of ice and atmosphere at the “equilibrium line,” the altitude where summer melt and winter snowfall are historically in perfect balance. “We probably have more information on nearby planets than we do on Greenland,” he says. “Parts of Greenland have never been measured, because few satellites can see that latitude, and those that can haven’t been up long enough. And it’s difficult to deploy surface instruments in those conditions.” Steffen’s aim was to begin filling in gaps in scientists’ understanding of the processes that drive-and are affected by-changes on the vast body of ice that holds roughly 8 percent of the world’s freshwater supply.
But near the Earth’s poles, equilibrium isn’t what it used to be. A few years after Steffen built his research station, he noticed that temperatures on Greenland’s ice cap were rising-and then rising faster. Over a decade, the average winter temperature shot up 7F, an increase so improbable that at first Steffen declined to publish it, fearing an error in his calculations.
Then again, he didn’t need to double-check his data to see that the ice cap was changing. Swiss Camp’s weather towers, which hold solar-powered monitoring equipment atop bases set 13 feet deep in the ice, began toppling over. In 1997 Steffen flew over Jakobshavn glacier in west Greenland and was shocked to see that its tongue had collapsed, “as if somebody had hit it with a massive hammer.” A speed check showed that Jakobshavn, already the world’s fastest-moving glacier, was accelerating; its velocity would double between 1997 and 2003.
A glacier that accelerates with a warming atmosphere is within the realm of scien-tific expectation. But according to the conventional wisdom of glaciology, the massive ice sheets that cover most of Greenland and Antarctica should respond much more slowly to variations in temperature, with appreciable changes happening across hundreds and thousands of years. Yet Steffen’s ground-based instruments and satellite data were showing that the ice under Swiss Camp was accelerating as temperatures rose, flowing at speeds of up to 20 inches a day as ice melted in places where it had once stood solid. Seismographs picked up increasingly frequent ice quakes, as the 5,000-foot-thick ice cap lurched toward the sea. By 2006, Greenland’s ice sheet was shedding some 150 gigatons per year-a mass surpassing all the ice in the Alps. “We realized that something was going wrong,” Steffen says. “Greenland was coming apart.”
CANARY ON THE ICE CAP
In the annals of polar science, Konrad Steffen will go down as one of the legends. Koni, as he is known by his friends and colleagues, oversees an annual budget of $50 million and a staff of 550 at the Cooperative Institute for Research in Environmental Sciences (CIRES) in Boulder, Colorado, a research center that is jointly funded by the National Oceanic and Atmospheric Administration and agencies like NASA. But Steffen has had the most influence not as an administrator but as an icy-boots explorer. He has spent the past 32 summers in the high Arctic, working in Alaska and Canada before settling on Greenland, where his Greenland Climate Network serves as the eyes and ears for climate scientists worldwide. In this extreme environment, the on-the-ground reality was invisible until Steffen personally customized and deployed much of the instrumentation that tells the scientific world, hour by hour and year by year, the conditions on the Greenland ice sheet and how they’re changing.
The news isn’t heartening. In fact, new data that Steffen and his colleagues are just beginning to truly understand suggest that the seemingly dire warnings in the recent reports from the U.N.’s Intergovernmental Panel on Climate Change (IPCC) may turn out to be profoundly understated.
Climatologists have found that the best places to study global warming are the coldest regions on Earth. The Arctic, the Antarctic and the world’s highest mountains respond to temperature changes more rapidly and dramatically than anywhere else on the planet. Greenland, especially, has become a kind of barometer for the rest of the world because of its sensitivity to climate changes and because its ice sheet-which Steffen calls “the weather machine of Europe”-exerts a tremendous influence on many of the Northern Hemisphere’s ecological cycles. Meltwater from the Greenland ice sheet is the largest potential contributor to sea-level rise, so what happens in Greenland over the next decade will answer key questions about how the rest of the Earth will fare in the next century.
This year, researchers from some 60 nations are participating in the International Polar Year, an intensive burst of interdisciplinary research focusing on the polar regions. Thus far, the data the researchers have seen-much of which was harvested from Steffen’s Greenland Climate Network-has been alarming. Water from the melting ice sheet is gushing into the North Atlantic much faster than scientists had previously thought possible. The upshot of the news out of Swiss Camp is that sea levels may rise much higher and much sooner than even the most pessimistic climate forecasts predicted.
THE PILGRIMAGE TO SWISS CAMP
Koni Steffen doesn’t look like a worried man when I catch up with him on a mid-April afternoon at the airport in Albany, New York, the layover in his annual pilgrimage from Boulder to Greenland. Steffen is tall and wiry, with stringy brown hair and a graying beard. He has intense, grayish-blue eyes and the furrowed, leathery cheeks you might expect of a man who has spent more than half of his 55 summers squinting into a bitter wind. In his speech, I can hear the lilting inflections of Schweizterdeutsch (Swiss German), the “secret language” he speaks at home with his wife and two children.
The three duffels Steffen tosses into my Jeep don’t hint at the 82 cargo boxes he has shipped ahead, after two all-night packing binges. The next morning-at 4:30 a.m., to be precise-Steffen, his crates and his three graduate students will board a C-130 at the Air National Guard base in Schenectady. The plane, which is outfitted with retractable skis, will make a long, slow flight to Kangerlussuaq, on Greenland’s west coast.
From there, Steffen and his team will board a ski-fitted Twin Otter to southern Greenland, where they will be left alone on the ice sheet. Working through the nights and sleeping “only when necessary” to get everything done before bad weather socks them in, they will spend the next three days leapfrogging northward from one location to the next, repairing equipment and setting up new weather stations. “And then,” Steffen says, his eyes lighting up, “we’ll arrive at Swiss Camp.”
Swiss Camp, located 3.5 degrees north of the Arctic Circle, is a collection of three semipermanent tents and a vestibule that doubles as a sauna. Steffen and his team typically arrive at the camp in late April, when night temperatures hover at around â€25F. A day’s (or night’s) work might include chiseling gear and work space out of solid ice, coaxing frozen equipment back to life, or hiking 10 miles back to camp from a broken-down snowmobile. “I have to make sure my grad students are very fit,” Steffen says.
Shortly after arrival at Swiss Camp, Steffen often sets out alone on his snowmobile-packing a sleeping bag, a pack of Marlboros and a satellite phone-to scout a path through the ever-changing landscape of cliffs, meltwater lakes and deep crevasses that lie between the camp and the weather station. The station, 10 miles away, is set in a jumbled ice field stuck with poles holding aloft monitoring equipment that ranges from basic weather instruments to radio spectrometers, GPS units and seismographs.
“I remember when I first arrived at Swiss Camp,” says Waleed Abdalati, a former graduate student who now directs the Cryospheric Sciences Branch of the NASA Goddard Space Flight Center. “I was thinking, What are the odds of this stuff making it through even one winter? And now, 18 years since he first set it up, if you made a list of the scientists who have used those data sets, it would be huge. Without Koni, the body of knowledge about Arctic climate, warming and melting dynamics would be severely limited.”
MARLBORO (AND ESPRESSO) MAN
Steffen’s contemporaries marvel at his ability to attract talent and long-term funding to his research projects-and at his capacity for work. At CIRES, Steffen supervises several ongoing field projects funded by NASA and the National Science Foundation. As a University of Colorado professor, he mentors a handful of graduate students while also teaching graduate-level classes and working on his own research. He has authored or co-authored more than 50 peer-reviewed scientific papers, and he is one of the few scientists who advises both Al Gore and the Bush administration.
“He only sleeps three or four hours a night,” says Jason Box, a former Steffen protg now at Ohio State University’s Byrd Polar Research Center. “There has been some speculation among us that he isn’t actually human. Some of his students believe that he has espresso running through his veins.”
Indeed, a strong cup of coffee is the first thing on Steffen’s agenda in Schenectady. We park downtown and walk toward a caf in a cobbled courtyard, stopping outside to allow him a quick cigarette. “I quit once,” Steffen says, “for 24 hours, in 1978.”
As he smokes, he tells me how. In the late 1970s, Steffen spent two winters on an ice floe in Lancaster Sound, near Baffin Island, collecting data for his doctoral dissertation. While traversing a glacial slope, he set off an avalanche and was knocked from his snowmobile. He woke up some time later in a blizzard, with a dislocated jaw and a bone protruding from his lower leg.
“I couldn’t get the Ski-Doo started,” he says, “and my leg was hanging loose. I dragged myself to a place where we had put an aluminum stake to mark a measuring point. I pulled out the stake and used it to straighten my leg. Then I pushed the snowmobile on its side to get some shelter. I had to get up on my good leg every half hour to jump around, to keep the circulation going. Smoking was out of the question, because I knew that if you smoke, you open your blood vessels; I would freeze to death.”
When the storm died down, eight hours later, his research partner, Karl Schroff, began searching for him on foot. (Their other snowmobile had broken through the sea ice and sunk a few days earlier, dunking Steffen in 30F water.)
“Karl was on the top of the ice sheet,” Steffen recalls, “and he could hear something like krrrack, krrrack. He knew this kind of a bird did not exist there, so he followed the sound. It was me yelling his name, with no voice left.”
Schroff left Steffen with a piece of chocolate and went back to their camp to radio for help. After no one replied to his first round of mayday calls, he fell asleep from exhaustion. A few hours later, he woke and tried again. This time he reached a U.S. Air Force plane, flying toward Thule AFB. A Canadian rescue party eventually plucked Steffen off the ice, 24 hours after he was knocked off his snowmobile. In his pocket was a farewell letter to his then girlfriend, now his wife. “I still have it,” he says. “I never gave it to her.”
“Anyway,” Steffen says, stubbing out his cigarette, “it was good to know that I could quit if I really needed to.”
THE SECRET LIFE OF ICE SHEETS
For the past 14 years, NASA glaciologist Jay Zwally has been Steffen’s regular partner on the Greenland ice cap. When they were young scientists, conventional wisdom held that ice sheets, unlike glaciers, respond extremely slowly to warming, losing substantial mass only over hundreds of years as meltwater runs off the top or evaporates. But as Zwally and Steffen looked at their data trends, they suspected that another process must be at work. “This is not just melting,” Steffen says. “You cannot melt this much ice this quickly.”
They theorized that meltwater on the surface of the ice cap was draining through fissures down to the bedrock nearly 4,000 feet below. To test the theory, they installed a network of GPS transceivers, accurate to a few centimeters. They compared the GPS measurements with data from satellites, ground-penetrating radar and other instruments. Then, in a 2002 paper that jolted the scientific community, they concluded that ice-sheet flow accelerates with surface melting, similar to glaciers.
“We call this phenomenon ‘dynamic response,’ ” Steffen says. “What happens is that the melting accelerates as meltwater funnels down to the bedrock. At the bottom, the water acts as a lubricant, flowing under the outlet glaciers and allowing the ice to slip into the sea more quickly. We hadn’t expected that ice sheets could react to warming so quickly. But that is the kind of feedback we are coming to understand in the Arctic; it’s a very sensitive environment.”
The current acceleration could be a short-term adjustment to the warmer temperatures, Steffen says, or it might last much longer. But some scientists, including lead NASA climatologist James Hansen, believe that Zwally and Steffen’s observations, coupled with new data from Antarctica, suggest that a major polar melt may be commencing. They point to a phenomenon called the albedo effect, in which melting ice exposes more land and water, causing the earth’s surface to become less reflective, and to absorb more of the sun’s energy.
In a 2005 article in the scientific journal Climate Change, Hansen wrote that the current pace of melting, driven by the buildup of greenhouse gases in the atmosphere, could lead to a self-reinforcing and perhaps unstoppable cycle of feedback that could result in the total disintegration of the Greenland ice sheet. Hansen and many other climatologists believe that it is likely that the ice sheet will begin melting uncontrollably if global temperatures climb more than 3.6F. A rapid meltdown in Greenland would quickly raise sea levels around the world and flood coastal cities and farms. As well as sending large icebergs down the coast, the infusion of cold, fresh water could disrupt ocean currents such as the Gulf Stream, which help to keep the weather in the Northern Hemisphere regulated. “If that feedback kicks in,” says Steffen, “then the average person will worry.”
But because dynamic response is so poorly understood, it has not yet been incorporated into the numerical models that climatologists use to project sea-level changes. For this reason, the potential influence of dynamic response on sea-level rise wasn’t factored into the sea-level projections in the “Climate Change 2007” report that the IPCC released earlier this year.
A consensus of hundreds of scientists from 130 countries, the IPCC report concludes that the warming of the climate “is unequivocal,” as evidenced by rising temperatures, widespread melting of snow and ice, and rising sea levels. The report, essentially a meta-analysis of 70 climate-modeling studies, predicts a long, slow deglaciation of Greenland and West Antarctica, and a global sea-level rise of 13 to 19 feet “over a period of time ranging from centuries to millennia.” By 2100, the report projects, sea levels will rise by 7 to 23 inches.
After protests by several prominent climatologists, the IPCC authors qualified their projection with a footnote acknowledging that dynamic ice-flow processes “not included in current models but suggested by recent observations could increase the vulnerability of the ice sheets to warming,” and raise sea levels further.
“Dynamic response is the elephant in the room,” says Martin Truffer of the University of Alaska’s Geophysical Institute. “We know well enough that there’s likely to be a higher sea-level rise than the IPCC was willing to project. They are trying to be cautious and conservative. But their conclusions lag behind the latest findings.”
Over dinner, I press Steffen to make a rough prediction on sea-level rise by 2100, based on his understanding of current trends. “Unfortunately,” he says, somewhat hesitantly, “I think we are looking at more like a meter.”
A one-meter (three-foot) rise in sea levels over the next 93 years would have enormous consequences, flooding low-lying coastal areas and megadeltas, such as the Nile and the Brahmaputra in Bangladesh, where millions of people live. Presumably, developed countries such as the U.S. and the Netherlands would be able to cope with sea-level increases by building new systems. But hundreds of millions of impoverished coastal dwellers in vulnerable places like Bangladesh, Indonesia and the west coast of sub-Saharan Africa could become refugees. One recent study predicts that the dramatic effects of climate change could push the number of displaced people globally to at least one billion.
In the Arctic, by far the fastest-warming place on Earth, rising air temperatures have already brought more fog, snow and spring rain to the people who live around Greenland’s habitable fringe. This in turn causes more melting of the ice cap, which sends more freshwater into the ocean, disrupting currents and bringing more warm water to the bays, which breaks up more sea ice . . . and so it continues, in an ever-warming cycle. “When I visit my friends in the villages,” Steffen says, “I realize it’s not just about the melting ice cap. It changes the climate along the coast, and it changes everything going along with it.”
On much of the coast, the polar bears relocated and the sea ice disappeared earlier this decade. Steffen expects the mosquito population to explode, making summer a misery. In the Greenland village of Ilulissat, locals can’t use their sled dogs to travel to other villages or to hunt the whales and seals that used to get trapped in frozen bays. Dogs in native communities in the Arctic are working animals; with no work for them to do and no seal scraps to feed them, their owners are killing off the canine population by the hundreds.
HOW TO BE AN OPTIMIST
It can’t be easy to herald a potential planet-wide catastrophe. But despite all the bleak data being mined from Steffen’s network, he says he is enjoying his work more than ever.
“For one thing,” he says, “people are starting to listen, to pay attention to science. Even politicians are starting
to understand that we have a higher level of CO2 in the atmosphere than at any time in the past 600,000 years, and that our future depends on whether we can get greenhouse-gas emissions under control.
“We are at a fork in the road,” he continues. “We could take action now and reduce our carbon footprint. That doesn’t mean reducing our standard of living or going backward. We can move forward, but in more efficient ways. We can still make money by building and selling the cleanest technology possible. But if we continue to build coal plants and sell them to China and India, then we are thinking short-term; we are not thinking of our children.”
This year, Steffen will add two more weather stations to his network, as well as more GPS and seismic instruments to record ice quakes. He will also attempt to descend into a moulin, a vertical shaft that channels rushing meltwater down to the bedrock. If all goes well, he will install laser instruments that may lead to a new understanding of the dynamics of ice-sheet plumbing. Both Steffen and Zwally suspect that moulins, which move meltwater and the heat it carries almost a mile through the ice, have a potentially significant effect on the health of ice caps and, by extension, on climate change around the world.
After a double-espresso nightcap, I drop Steffen off at the Holiday Inn. It’s now 12:30 a.m., three hours before wake-up call. At the reception desk, polar scientists and their support teams are still straggling in, hoping to catch a few hours’ rest. It’s looking like it’s going to be a crowded flight up to Kangerlussuaq. “That’s another good thing,” Steffen says. “I’m no longer working alone. Now we have teams of physicists, geographers, atmospheric chemists, geologists, engineers and many others who have the same interest in the science of the environment, seen from different perspectives.”
Many of those researchers became part of what NASA’s Abdalati calls “the ice-sheet community” as Steffen’s protgs. Abdalati himself still has a vivid memory of his first landing on the Greenland ice sheet, accompanying Steffen as a young Ph.D. candidate. “It was windy and cold and just unbelievably bleak,” he says. “The helicopter put us down and then it took off, and we were left in this cold silence, alone and hearing nothing but the wind.” It was, Abdalati says, among the loneliest moments he had ever experienced. Then he looked over at his mentor. “Koni was leaning backward, arching his back, with his arms wide open. He was in his element, just reveling in it. And I remember thinking, ‘Here is a man who is really doing exactly what he should be doing.'”
Tom Clynes wrote about the future of energy in the July 2006 issue.
