A Day in the Life of an Arctic Soil Scientist

Freezing temperatures, biting wind, bad roads, swarms of bugs—it's easy to imagine facing all of these travails while doing soil science in the Arctic. But not being able to keep samples frozen? That's harder to picture, and yet it's precisely the problem Jessica Ernakovich encountered the first time she headed to Alaska. Invited to be another “set of hands” on a friend's research trip, Ernakovich thought she'd collect a few permafrost samples of her own to take back to Colorado. But no matter what she tried—insulated blankets, dry ice (procurable at many Alaskan grocery stores, it turns out)—by day's end, the once permanently frozen soil was “just a big puddle,” says the former Colorado State University graduate student, now a postdoc at CSIRO in Australia. Ernakovich adds that she quickly learned to select field sites near research stations with ample freezer space, and you hear the same time and again from scientists who work in the Arctic. “Logistics,” echoes Amanda Guy, a Ph.D. student at University of Saskatchewan, when asked why she and her adviser troubled with a new in situ technique for measuring soil carbon, rather than just shipping soil home for analysis. “Doing Arctic fieldwork is very costly,” she says, “especially when you're sending lots of samples down south.” Down south, the hardship often continues. Ernakovich, for example, spent months after one Alaska trip processing frozen bricks of permafrost in a –10-degree freezer. But the pull of the north is also hard to resist. Not only is the Arctic a fascinating place scientifically, it's lovely to behold. And alongside the challenges are great joys: seeing migrating caribou and the Northern Lights. Or eating cheese or “anything else with fat” after a cold, hard day in the field, Ernakovich says with a laugh. “It was one of those once-in-a-lifetime opportunities,” Guy says of her Ph.D. project. “You know, who gets a chance to go up there?” Here's what else the pair had to say about studying soils in some of the world's most remote and inhospitable places. One dictionary definition of logistics is “the handling of the details of an operation,” and in the Arctic, details really matter. “You have to take everything with you,” Ernakovich says. “There's no running to the grocery store to pick up more plastic bags or something.” But the planning goes way beyond remembering to pack all needed equipment and supplies. Most critical is deciding what equipment to bring in the first place and whether it will work in the field as intended. Ernakovich, for instance, thought long and hard about where in the region she'd be able to extract cores of permafrost safely by herself. Many soil scientists in Alaska use gas-powered ice augers retrofitted as soil-coring devices to drill into frozen ground, but the equipment can be hairy to handle. Hit a rock and you could get thrown off the auger and injured, Ernakovich explains. The expensive auger also has no reverse gear, meaning it's likely to become a permanent fixture of the tundra if it gets stuck during drilling. Jessica Ernakovich heading out to sample permafrost soils at Sagwon Hills, AK, in August 2009. So, in the end, she settled on the Sagwon Hills, near the Toolik Biological Station. There the permafrost is formed of deep loess deposits—fine, silty material that poses little risk for such mishaps. Of course, there was good scientific justification for the site, as well. “It represents the type of carbon-rich permafrost that you often find in Alaska,” says Ernakovich, who studies the impact of microbes on decomposition of thawing permafrost soil. “That was important to me.” For Guy, whose research took her to Ellesmere Island in the Canadian High Arctic, equipment was an even bigger deal. She and her Ph.D. adviser, Steve Siciliano, study polar deserts: cold, arid stretches of permafrost with scant plant cover, but—as Siciliano recently discovered on Ellesmere—surprisingly high fluxes of greenhouse gases. After finding them, Siciliano decided to do an extensive survey of soil organic carbon in the polar desert using a new, field-portable visible and near-infrared (vis-NIR) spectrophotometer. Guy was enlisted to develop it. “The method was supposed to be just one line in my thesis,” she notes wryly. “But we quickly realized it required a lot more than that.” She has since spent hours refining computer models—models that will eventually let her convert the spectral data she collected on Ellesmere Island into soil carbon values. But before this, she and Siciliano had to figure out how best to use the new instrument in the field. A relatively small but unwieldy and heavy thing, the vis-NIR device sits with a laptop computer in an open-frame backpack. A soil probe is then carried by hand, along with a small generator and jerry cans of fuel. At first, Guy says, she and Siciliano “hauled it around quite inefficiently.” But by the second season, they'd figured out how to design a sampling scheme around the instrument—finding the midpoint of a grid and then moving systematically out from there, so that they didn't have to walk as far between points. Even so, “You get quite strong carrying it around,” Guy says. But the extra work was also well worth it, netting in the end more than 10,000 soil measurements. “It would have been completely unfeasible to send 10,000 samples south,” she says. “That's why we wanted to see if we could use this instrument.” Logistical hurdles like these are why soil sampling in the Alaskan Arctic has historically paralleled major roads—particularly the Dalton Highway, or “haul road.” Running from Prudhoe Bay's oil fields in the far north to Fairbanks in the south, this thin ribbon of civilization gives soil scientists ready access to Alaska's interior. But this hardly means the highway is civilized. Its isolation, frigid temperatures, potholes, and fierce winds routinely land it on lists of the world's most dangerous roads. Amanda Guy using visible and near-infrared (vis-NIR) spectrophotometry. “There was even an ‘Ice Road Truckers’ show one season,” Ernakovich says, referring to an episode of the History Channel's Dangerous Missions TV series. “So it's kind of crazy that you're then just pulling off this road to do your research.” The Dalton Highway in Alaska. Photo by Flickr/Terry Feuerborn. There was something else to worry about, too, as Ernakovich worked alongside the highway one season: hunters. They aren't supposed to discharge guns within three miles of the road, but Ernakovich and her companions took no chances. The scientists waved at hunters every chance they got to show that they weren't caribou. Guy, Siciliano, and their colleagues relied more on helicopter transport than roads—for the simple reason that roads don't exist on the polar desert mountain where they worked, called the Dome. Their second year, for example, the researchers were flown onto the Dome for a month, setting up camp with tents, portable toilets, and field stoves (but no showers, Guy notes) and hiking down a few times to a base camp in the lowlands to store samples in a freezer. When it came time for the helicopter to fly south for the season, however—taking the researchers’ equipment with it—the team wasn't done with its fieldwork. So after that, they trekked up and down the mountain constantly from the base camp across unstable talus slopes and steep inclines. Above: Researchers were flown to the polar desert mountain known as the Dome where they set up camp with tents (below, view from a tent). Another vivid memory Guy has of the Dome are the katabatic winds: fierce, unrelenting winds that blow downslope from nearby glaciers. The group's first indication they were coming was a series of long, pancake-like clouds in the sky. After these were spotted, there was nothing to do but throw rocks on top of food and equipment, and into tents—anything that could blow away—and then hunker down until the storm abated. “The wind is just crazy-strong, and it can go on for quite some time. So it definitely affects your fieldwork,” Guy notes with understatement. Some of Ernakovich's most trying times took place not while she was in the Arctic, but after she returned to her Colorado lab. It's one thing to be cold and uncomfortable amid the grandeur of the tundra, she explains—quite another to be closeted inside a –10-degree freezer, where she and her undergraduate assistant, Alisa Challenger, crushed up bricks of frozen soil for six long months. “In a lot of ways, I felt colder in the freezer with the fan always blowing on me than I did in the Arctic in winter,” Ernakovich says. What's more, not only did she and Challenger bundle themselves in winter boots, hats, gloves, and down jackets against the cold, but they also donned “triple extra-large” sterile gowns and face masks to maintain aseptic conditions. “We looked like we were about to do surgery, but like clowns doing surgery,” she says. “It's one of those things you look back on and think, ‘That was crazy!’” Yet, while she's not eager to toil inside a freezer again anytime soon, Ernakovich is very keen on returning to the Arctic. In fact, she chose her postdoc at the other end of the world—Australia—expressly to learn techniques with application, she believes, in the frozen north. It's not just the adventure of being there or the stark beauty of the landscape. Ernakovich is brimming with new research questions. She wants to know the place as deeply as one possibly can. “Once you go north and see it,” agrees Guy, “you really want to do good science that does it justice.”

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