Science on the Ice
The last section of camp is the area where most of the science at WAIS Divide has taken place. It consists of the Arch and two tents. This area is the farthest from town, about a quarter mile walk along the power lines.
When navigating in hard-to-see conditions, it is easiest to follow the lines from town (far right) to the Arch and two science tents.
The Arch
The Arch was constructed in 2005-06 to house the drilling equipment for extracting the WAIS Divide Ice Core. There are two sides to the huge metallic structure – the drilling side and the core-handling side.
On the drilling side, scientists operated the machinery that cut and extracted sections of ice core, two meters at a time, for a total of 3405 meters!
On the core handling side, sections of ice core were marked, logged, and packaged to be shipped to the National Ice Core Laboratory (NICL) in Colorado, USA. Because it was very important that these cores did not melt, this side of the Arch was actually air conditioned to a temperature of -20C or lower!
This NSF video describes the tools used to extract an ice core and the facility where it happens – the Arch:
Currently, we use the borehole in the Arch to lower instruments and collect data about the dynamics of the Ice Sheet beneath us.
You can see, from the high ceiling, why this building is called the Arch.
A view of the top of the borehole, which starts about 10m below the Arch floor. When not in use, the borehole is covered by the white plastic lid seen beside it here. The borehole extends about two miles straight into the ice sheet below it!
By the end of this field season, all of the ice core equipment that remains in the Arch will be taken apart and shipped away from WAIS Divide. The Arch is all-but-buried under the past decade of snowfall; scientists, technicians, and USAP staff are currently considering the best course of action for dismantling and removing the Arch.
The Science Jamesway
Close to the Arch, there is a heated Jamesway that most science teams use as a staging area for their work. We have tables where our equipment can be laid out and assembled, a table for our computers, and a table for tea and snacks (which me and Tiffany were in charge of setting up)!
The Science Tent, partially hidden from view by our official mode of transport, the snowmobile/sled.
Here, Erin and Mike make final adjustments to our acoustic televiewer before we begin our data collection.
Grad student, Merlin, works on an optical televiewer, to collect data about the fabric of the ice sheet.
There is also a cot in this tent... for those scientists working late shifts or working so hard that they can't make it back to Tent Village.
The Winch Tent
Next door to the Science Jamesway, the Winch Tent sits atop of the Arch.
The red tent houses the winch and is unheated, since its floor is the top of the Arch.
Meet Bessie the Winch, a 20+ year old giant spool of cable, who requires two staff to operate and makes all our science possible. The winch cable is fed through a small hole in the ceiling of the Arch, and connects to instruments that are lowered into the borehole to collect data. There is enough cable to lower the instruments all the way to the bottom of the 2-mile borehole.
Bessie, the winch, without which almost none of the science teams could do their work at WAIS Divide this year.
The cable from the winch goes through an ice tunnel, into a hole cut out of the top of the Arch, and down into the borehole.
In the Arch, our data collection tool is connected to the winch cable to be lowered into the borehole. Erin peers over the railing to check the alignment.
The winch cable has wires in it that transmit data from the connected instrument back up to computers and other monitors. This allows us to see exactly what our instrument is seeing every centimeter of the way down the borehole, including the temperature, the tilt, and the pressure.
Goldie Blox checks the data coming in from a depth of 2615.86m under the ice!
When we are actively collecting data, we spend hours at a stretch in the Winch Tent, sometimes overnight. This tent, by far the coldest one we regularly work in, has a table for our computers and monitoring equipment, a couple of space heaters that don't work very well, and Bessie, of course.
Jim, one of two operators, adjusts the speed settings on Bessie, the winch.
Working hard, for science!
Soon, we'll introduce you to Ana, our acoustic televiewer, and the first instrument we are using to conduct our research at WAIS Divide.
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