Poised for the plungeWISSARD team ready to explore subglacial Lake WhillansPosted January 14, 2013
The final push by a team of U.S. Antarctic Program (USAP) scientists to explore a lake nearly a kilometer below the ice sheet is about to begin. Researchers were scheduled to start flying from McMurdo Station to the edge of the West Antarctic Ice Sheet this week. Their destination: subglacial Lake Whillans, a liquid body of water trapped under about 800 meters of ice. Their mission: To retrieve water and sediment samples from the lake to learn what sort of life might exist in such an extreme environment. More on subglacial Lake Whillans
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Magical realism: WISSARD project poised to explore subglacial Lake Whillans Project Website — WISSARD.org Facebook Page — WISSARD The exploration of the subglacial lake, one of nearly 400 now known to exist under Antarctica’s massive ice sheets, may also offer insight into how the water influences the movement of the glacial ice above. Lake Whillans is part of a regional subglacial waterworks that fills and drains periodically, eventually emptying into the Ross Sea under the Ross Ice Shelf . Scientists also hope to learn some basic facts about the geology and chemistry of such a lightless aquatic system. In addition, the muck and mud below the lake floor could contain clues about the geologic history of Antarctica, as well as the ebb and flow of its ice sheets through time. In other words, there’s a lot to learn from Lake Whillans. And not a lot of time to do it. After years of planning, instrument development and construction of a new hotwater drilling system, the scientists on the Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project may only have a few days to explore what many consider the last frontier in polar research. It’s a lot of pressure. And quite exciting, according to Ross Powell , a professor at Northern Illinois University and one of the three scientists on the WISSARD executive committee. The project is mainly funded by the National Science Foundation’s Office of Polar Programs through the Antarctic Integrated Systems Science program. Photo Credit: Peyton Adkins
The WISSARD tractor traverse begins its journey to subglacial Lake Whillans.
“Thinking that we could be the first group to look at one of these things is certainly something that drives everybody. It certainly drives me,” Powell said a few hours before a modern-day wagon train of Case and Challenger tractors completed the two-week journey across the Ross Ice Shelf to the field site on Jan. 13. The tractor traverse had just hauled some 18 containers of cargo, science labs and the hotwater drilling rig and platform across the Texas-sized ice shelf. They had left McMurdo shortly just before New Year’s Day following a series of tests of the drill and science equipment. “I thought the test went really well. It was a good test because we found out where there were some problems, which we have now had time to solve. We are now set to go,” Powell said. During December, the WISSARD team spent most of the month on the 60-meter-thick McMurdo Ice Shelf putting the drill and equipment through a dress rehearsal. It was the first time the entire operation had been put together in one place. Photo Credit: JT Thomas
Drillers Daren Blythe and Dar Gibson shovel snow into the snow melter providing water for the hotwater drill, which will melt a hole through 800 meters of ice on top of subglacial Lake Whillans.
The complex hotwater drill system — designed, built and operated by the University of Nebraska-Lincoln — uses a combination of off-the-shelf components such as hot pressure washers, equipment salvaged from the IceCube Neutrino Observatory project at the South Pole Station , and some custom-made pieces. It will bore a 60-centimeter hole through the ice over Lake Whillans in about three days. The choreography of the operation requires more than just sending a vertical parade of science instruments down the borehole to collect various water and sediment samples, as well as take scientific measurements. Water used by the drill must be filtered and equipment sanitized to ensure the pristine lake environment isn’t contaminated — or that biological samples aren’t somehow compromised. Water entering the borehole will pass through a series of filtration modules. The hotwater drill equipment and science instruments will be treated to eliminate particles and microbes from reaching the lake water. Everything will pass through a UV collar around the mouth of the borehole for a zap of sterilizing radiation. The clean access protocols are necessary but time-consuming, as the team discovered during the test phase. “It certainly adds to the complexity and time of operations,” said Powell, one of about a dozen principal investigators on the project. |
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