University of Maine professor Brenda Hall has been on 27 polar expeditions. We have been on exactly zero. But recent news about a crack in an Antarctic ice shelf that has been growing by leaps and bounds in the last few months made us very much want to speak to someone who had and might be able to provide perspective. As luck would have it (well, our luck, her regular work schedule), the teacher and researcher with UMaine’s Climate Change Institute got back just a few weeks ago from a six-week research trip in Antarctica. We talked with her about her journey from growing up in Standish to being a globe-trotting expert on glacial geology and the stability of ice sheets.
DID YOU ALWAYS KNOW? When Hall was 10 or 11, her grandparents took her to a family reunion. There were lots of extended relatives there, most of whom she didn’t know, and very little in the way of activities that appealed to a child. “I spent most of the time in the library reading.” She came across a book about glaciers. She doesn’t remember the title, only the subject matter. “It captured my imagination at the time.” In high school she took the whole range of science courses, including an earth science class. She went on to Bates College for her undergraduate degree, and that interest she’d had as a child became a career objective. A summer in the Canadian arctic doing field research on lakes with Bates professor Mike Retelle “really cemented” her desire to be glacial geologist.
THE GRADUATE: Hall went on to get her Ph.D. in geological sciences from the University of Maine. She’s now an associate professor of glacial and quaternary studies there and has research studies going in Greenland, South America and Antarctica. Her work, she said, attempts to reconstruct what the climate looked like in the past by studying glaciers. That establishes data that helps us understand natural climate change (the kind that happened before human beings and their cars and such came along). One of the big-picture questions that frames her research is: What prompts the earth to come out of an ice age? And no, there hasn’t been just one. More like eight or nine big ones occurring every 100,000 years or so, and before that, even more but closer together, roughly every 40,000 years. The question is one many scientists are trying to answer. “That is something I would be interested in knowing in my lifetime.”
UNPLUGGED: Hall’s studies have not focused on the Larsen C ice shelf (that’s the one the size of Delaware that is cracking and expected to calve, ie, break off from the bigger ice shelf, by March). Her work today is more about the ice’s past “from a few hundred years to a few thousand years.” Her most recent trip was on the Ross Sea, which is far enough away from Larsen C (and wireless) that she didn’t hear anything about what was going on with the deteriorating ice shelf. Or, actually, anything about the rest of the world; Antarctica may be the ultimate unplugged destination. “That’s one of the things I like best,” she said. “It is possible to get away from just everything.” But she’s up to speed with Larsen C now and in awe. “The speed at which it is happening is not unexpected, but it is still pretty amazing. I don’t want to say amazing in a good way.” This calving isn’t supposed to have an obvious impact on sea level, but it’s still worrisome. That’s because these ice shelves act “almost like plugs,” and long term, without it, Hall said, “the ice that feeds from the land starts flowing faster,” accelerating the melting.
EMOTIONAL FALLOUT? There’s not a lot of good news coming from the planet’s frozen north and south. Is it hard studying something that is being so massively negatively impacted by climate change, caused by humans, some of whom don’t even believe it’s happening? “Obviously it would be good to find something that suggests that maybe we don’t have to worry,” she said. “But generally, I try to just look at what the evidence says.” Take for instance, the increase in the velocity of the ice streams in Greenland. What used to be the fastest-moving glacier would move about 7 kilometers in a year, or a little more than 4 miles. “But since the early to mid-2000s, some of them started going 10 to 12 kilometers a year.” Not good for society, but fascinating to observe within a career. Hall maintains a scientist’s reserve: “You have to be just totally objective.”
DEFROSTING DINNER: It helps that Hall likes being in frozen places. “I absolutely love field work in Antarctica.” It is summer there, and near the Ross Sea, temperatures hovered right around freezing. The team of five researchers, including colleagues from the University of Washington, camp out in tents. It’s 24 hours of sun but, “I don’t have a problem sleeping. We get tired because most of our days are spent hiking around and going some fairly long distances.” They eat well, lots of frozen meats and vegetables, but it was so warm that near the end of this trip, their supplies thawed, dicey when it came to the meat. “We ate it when it was sort of borderline, but there was one day when you opened the cooler and said, ‘No more.’ ”
LIFELONG LEARNER: What’s the last new thing she learned? It was on this most recent trip, actually, which took her to a glacier she’d never been to before. “We found that there is actually quite a bit of plant life in these parts. I don’t mean grass, but a lot of lichens and even several kinds of moss. We may have found the most southern moss ever recorded.” Were they always there but not yet found? “They couldn’t have been there during the last ice age,” she said. “But there must have been little bits of land sticking up somewhere that they survived on. And then they colonized.”
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