A San Diego researcher was part of a team that was the first to discover large pools of ancient water under the ice sitting on Antarctica.
Scripps Institution of Oceanography postdoctoral student Chloe Gustafson traveled to the continent with a small team from San Diego and Columbia University.
“We imaged from the ice bed to about five kilometers and even deeper,” said Kerry Key, an associate professor of earth and environmental sciences at Columbia University and a Scripps Oceanography alumnus.
The small team spent several weeks setting up and monitoring special instruments to measure the electric and magnetic fields within ice sheets that can be hundreds of meters thick.
“Geophysics at its heart is really similar to medical imaging. It’s like taking an MRI of the earth just on a larger scale,” Gustafson said.
The research team picked a location on top of an ice stream, which is a region of fast-moving ice within an ice sheet. The sheets can flow orders of magnitude faster than the rest of the surrounding ice, moving up to 1,000 meters or roughly 3,280 feet a year. Some are as much as 50 kilometers wide.
“I like to think of ice streams as sort of slip and slides,” Gustafson said. “So, if you have water on a slip and slide you can slide along much faster than if there’s no water on your slip and slide.”
Ice sheets are the primary mechanism for Antarctica to shed ice into the surrounding ocean.
The presence of the ancient groundwater, some of it in huge reservoirs, could speed up the movement of ice above it. That, in turn, could accelerate the continent’s ice shedding, raising sea levels.
And the new information could also help scientists understand natural systems elsewhere.
“You can imagine a frozen lid over a liquid interior, whether it’s completely liquid or liquid-saturated sediments,” Key said. “You can think of what we see in Antarctica as potentially analogous to what you might find on Europa or some other ice-covered planets or moons.”
The findings are published in the May 6 issue of the journal Science.
