Page 3/3 - Posted January 31, 2011
WAIS Divide project still has work to do after completion of major coring phase
The completion of the major coring operation is “bittersweet,” said Matthew Kippenhan, WAIS Divide project manager for Raytheon Polar Services , the prime contractor to the NSF for logistical support.
“I’m truly feeling honest excitement about reaching this milestone,” Kippenhan said. “Still, we have another second half that has its own challenges.”
Kippenhan is referring to at least two more field seasons. WAIS Divide scientists plan to send instruments into the open borehole to collect additional information and samples. For example, volcanic ash layers in the surrounding ice detected by borehole logging will be useful for helping date the core.
By the second season, if not earlier, they also plan to drop down a new type of instrument called a replicate coring drill that the engineers at IDDO are currently designing and building. The smaller drill will fit into the original borehole and core into the side, retrieving additional ice for analysis from layers of particular interest.
The drilling this year stopped about 100 meters above bedrock, as the WAIS Divide scientists didn’t want to contaminate the basal system where ice, rock and water meet.
“The basal water system … has not been exposed to the Earth’s surface for millions of years, and [may harbor] a unique and pristine biological environment that the U.S. Antarctic Program does not want to contaminate,” Taylor said.
Still, the team may attempt to drill down as much as 40 meters next year if the borehole instruments tell them there is enough ice thickness “cushion” to go deeper without risking penetrating into the environment below.
Kippenhan’s bittersweet moment almost didn’t come this year.
Weather delayed camp opening by several weeks. Then mechanical problems with the drill cost a few more precious days out of the schedule. A five-day extension to the drilling season by the NSF made the difference in the end.
“We are hoping to get as long a record as possible from this site, and getting all of the ice we planned on this year will allow the science community do the work that they are funded to do,” Palais said. “Drilling the ice core is just the first step in the process, albeit a very important one.”
Analysis of the upper sections of the ice core is already under way at institutions and labs across the country.
The NYANG planes carry insulated boxes of the core back to McMurdo Station, where they are stored before being transferred to a cargo ship that visits the research base each February at the end of the summer field season. The frozen cargo is eventually trucked from the west coast to the National Ice Core Laboratory (NICL) near Denver where it is processed for shipment to participating universities. [See previous article: On the line.]
About 2,000 meters of ice has already passed through NICL. Brook at Oregon State University is awaiting the next — and final — delivery.
“It is really exciting to see this ice coming back to the U.S., and we are really looking forward to the data. Results from the core so far are excellent,” Brook said.
Many of the researchers will be keen to compare their results with those from a core of similar age extracted from Greenland over the last couple of years by a European-led team. However, heavy concentrations of dust in the Greenland ice affects the CO2 measurements, making the WAIS Divide core that much more valuable to scientists like Brook.
“The drilling crews and everyone involved in the whole logistics and science operations, from the U.S., through to McMurdo, to the camp itself, deserve a huge amount of credit for making this happen,” he said. “There were lots of obstacles, and pulling it off is a major achievement.”
NSF-funded research in this story: Kendrick Taylor, Desert Research Institute, Award Nos. 0944191, 0440817, 0440819 and 0230396 . For a complete list of all funded projects related to the project, see the WAIS Divide webpage of funded projects . The WAIS Divide Science Coordination Office , based at the University of New Hampshire , manages the day-to-day operations of the project.Back 1 2 3
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