WISSARD project poised to explore subglacial Lake Whillans
Posted November 9, 2012
It’s taken a bit of magic — not to mention an incredible effort by scientists, engineers and support personnel — but the WISSARD project is poised to explore one of the last frontiers on the planet.
The biggest research program of the post-International Polar Year (IPY) era for the U.S. Antarctic Program , WISSARD brings together more than a dozen principal investigators to delve into a subglacial lake buried nearly a kilometer below the ice sheet. [Find WISSARD on Facebook .]
The official name — Whillans Ice Stream Subglacial Access Research Drilling — only offers a hint about what this $10 million interdisciplinary project funded by the National Science Foundation hopes to accomplish over the next two years.
“We’re going into the unknown — one of the last frontiers — which makes it really exciting,” said John Priscu , WISSARD chief scientist and professor at Montana State University . “We’ve got every discipline involved. I think we’ve put together the best [people].”
Photo Courtesy: John Priscu/Antarctic Photo Library
John Priscu, with the Royal Society Range in the background.
The project is actually made up of three components, an alphabet soup of acronyms that captures the various research goals within WISSARD. Priscu also leads GBASE , for Geomicrobiology of Antarctic Subglacial Environments, which covers various aspects of the subglacial ecosystem — including the examination of life in this lightless, low-temperature, nutrient-poor environment.
“We’re ready for almost anything,” Priscu said of the search for life underneath the ice sheet.
Next up is LISSARD , Lake and Ice Stream Subglacial Access Research Drilling, which will focus on the interplay between the ice sheet and subglacial waterworks below, particularly how the water influences the behavior of the ice and its march to the sea.
The third component has the fiercest acronym, RAGES , for Robotic Access to Grounding-zones for Exploration and Science, a project that proposes to delve eventually downstream of Lake Whillans where the water, ice and bedrock meet in a dynamic dance of streaming, melting and freezing.
A professor at Northern Illinois University , Ross Powell is the lead PI for RAGES and is the third member of the scientific triumvirate for WISSARD. His group has been involved in designing and developing some of the scientific instruments that will be involved in sampling the lake.
“There’s complexity in developing the technology to do that,” Powell said in what could be considered something of an understatement.
A subglacial wetlands
There’s certainly nothing understated in what WISSARD proposes to accomplish in its multiyear study, particularly in the opening chapter that begins with the 2012-13 summer field season.
Even now, U.S. Air Force C-17 Globemaster III aircraft are hauling equipment and personnel from Christchurch, New Zealand, to McMurdo Station on Ross Island. By early December, scientists, engineers and support personnel plan to test the entire WISSARD system on the nearby McMurdo Ice Shelf.
The dress rehearsal includes everything from the complex hotwater drill system that will bore a hole through the ice sheet, to the instruments that will collect water and sediment samples from Lake Whillans, to the clean-access protocols that will help ensure the research doesn’t contaminate the lake.
Then it will be time to pack it all up and haul sleds of equipment across the Texas-sized Ross Ice Shelf to the field site on the eastern edge of the West Antarctic Ice Sheet.
“The United States has a history of working there,” said Priscu of a region where ice streams, faster-moving rivers of ice within the ice sheet, drain into the Ross Ice Shelf.
For example, remote sensing work by WISSARD colleagues like Helen Fricker at the University of California, San Diego , led to the discovery of an extensive subglacial waterworks system connected to the lakes. The satellites revealed the subtle rise and fall of the ice, as water filled and drained the lakes below.
“The subglacial environment is like a wetland, with the rivers coming through … with fairly large but shallow lakes that flow into other lakes,” Priscu explained.
Land o' lakes
Lake Whillans is one of about a half-dozen subglacial lakes known to exist under the ice streams near the Ross Ice Shelf. A series of previous studies — some directly in support of WISSARD, others predating it — have found that Lake Whillans is about 60 square kilometers but only about 10 meters deep.
In particular, WISSARD’s geophysical team has worked over the past few years to provide the borehole science group with unequivocal data on lake hydrology and morphometry, according to Priscu.
“Thanks to the excellent work by our geophysical team, we now know more about the basin characteristics of subglacial Lake Whillans than we do about lakes in the McMurdo Dry Valleys, which have been studied for more than 30 years,” he said.
Several hundred subglacial lakes have been identified since they were first discovered in the 1970s. Researchers with the British Antarctic Survey (BAS) , including colleagues from the United States, published an inventory in 2005 that tallied 145 subglacial bodies of water. The number is believed to be about double that today.
The largest and most famous remains Lake Vostok, which Russian scientists penetrated earlier this year after decades of drilling through the East Antarctic Ice Sheet, originally as part of ice-core research. A recent analysis from samples of lake ice stuck to the drill did not find any signs of life from Vostok, located more than 4,000 meters below the ice. That hasn’t surprised scientists, who say the sample was likely contaminated by petroleum-based fluid used to cool the drill and keep the hole open. [See previous article — Breakthrough: Russian scientists penetrate subglacial lake for the first time.]1 2 3 Next
About the Sun