The researchers will focus on doing measurements that will allow them to reconstruct the last 1,000 years of climate variability in this part of East Antarctica. They will take several ice cores about 70 meters long as well as shorter cores that will let them examine the last two centuries with more detail.
“By taking a couple of longer cores, we’ll get a nice record of the previous 800 years before the Industrial Revolution, so the changes since then would be much more obvious,” Neumann said.
One of Neumann’s tasks is to conduct stable isotopic measurements of snow and ice samples, a task he will perform once back in the United States and from the samples he and others take in the next few months.
By studying the isotopic ratios of the same element—oxygen 16 and oxygen 18, for instance—researchers can figure out what the climate was doing at a particular time because they can correlate different ratios with different types of climate.
The snow falls with one isotopic ratio. But after it sits around, that number can change because of interaction with the atmosphere.
“Every time water vapor moves around it can change the isotopic ratios,” Neumann said. “We want to study that to be able to better understand this process and account for it when trying to understand past climate.”
Another goal is to look at the surface distribution of stable isotope ratios, which are an important calibration tool for continental circulation models, Neumann said. This will tell researchers “about where certain precipitation is coming from and how much precipitation in different areas get.”
Albert will study the microstructure of snow and how the climate affects the snow’s physical properties. She will look at surface samples and the first 30 meters of ice for her work to understand the physical effects of accumulation rates on the snow.
“Snow as a natural material is always close to its melting point compared to other materials, such as soil,” she said. “Consequently, the microstructure of snow changes a lot in response to local temperature and changes in temperature, and it responds to changes in accumulation.”
Antarctica is a notoriously dry continent, with little precipitation. Most of what does fall occurs at the coast. Albert said the team can expect to see annual snowfall rates of up to 20 centimeters near the coast, tapering off to ice accumulation of less than 2 centimeters at the high, interior areas.
Another important component of Albert’s measurements relate to how snow’s physical properties affect radar signatures. “This will ultimately help us understand what the remote sensing images of Antarctica mean,” she said.
Taking flightRadar and remote sensors will play a big role in the project, from snooping out crevasses and mapping a route to measure the thickness of the ice sheet and the spatial distribution of snowfall.
One of the more whiz-bang instruments at the team’s disposal is an unmanned aerial vehicle (UAV). The UAV, with a wingspan of nearly four meters, will be launched at each major stop along the traverse route—about nine in total.
“We have an 18-foot-long catapult and use compressed air to launch the plane,” explained Stian Solbø, a research scientist with Norut, a research institution in Norway. Solbø will be on the expedition running the UAV as well as taking GPS and ground-penetrating radar readings.
The UAV carries meteorological instruments, radar and a digital camera. “The radar will be used to measure the thickness of the annual snow layers and the camera images will be used to determine the roughness of the surface, which is important when modeling the redistribution of snow due to winds,” Solbø said via e-mail.
“The flights will be at 600 feet above the surface, which is a compromise between the range of the radar and the area covered with the camera,” he added. The drone will range hundreds of kilometers from each launch site.
“Operating a UAV at the altitude and temperatures of the plateau is very challenging, so this project carries a considerable risk of equipment failure,” Solbø noted. “As anyone living in the Arctic [knows], materials and equipment behave differently at 40 [degrees] below [Celsius] and things break very easily, and all work has to be done with gloves on, so we have attempted to make the system glove proof.”
Getting togetherIt’s also not easy for people to work at those types of temperatures and altitude.
Each person on the traverse team was chosen for his or her strong polar background, as well as for multiple skill sets, according to Winther. The team is balanced between Norwegian and American scientists.
“It’s a very experienced team that can handle and cope with the challenges that we will meet, like low temperatures and long days and the remoteness,” he said.
For instance, Neumann has worked previously with the International Trans Antarctic Scientific Expedition (ITASE), a similar project that has carried out traverses in other parts of the continent and that will also make a bid for South Pole this season.
This will be Albert’s first traverse, but she has deep-field experience in the Antarctic studying megadunes on the East Antarctic plateau three years ago. “Personally I’ve tried to prepare myself physically, mentally and emotionally. It’s a very long time, and under very severe conditions,” she said.
Though he lives in the Arctic, Solbø said he hasn’t experienced the sort of temperatures the team will encounter on the plateau and will bundle up appropriately. “I have also attended a course on glacier safety given by the Norwegian Polar Institute, where we have trained on rescuing people from crevasses,” he said.
Fifteen people will set out on the expedition from Troll, including three members of the media to document the early weeks of the trip. The journalists and two scientists, along with some cargo, will be airlifted out before the rest of the team continues to the Pole.
Except for that one flight, the traverse will be entirely self-supported. Four tracked vehicles will pull two sleds, some full of fuel and equipment, with others serving as living and working quarters. And everyone will get a chance to work on his or her culinary skills, Albert said.
“We really operate as a team,” she said. “Everyone knows what’s going on. Everyone has a chance to contribute to the discussions. We all share in the joy of discovery and we all share in the menial tasks that must be done.”
NSF-funded research in this story: Mary Albert, Dartmouth College.
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