UNIVERSITY PARK, Pa. — A more comprehensive way to understand the fracturing of Greenland's Helheim Glacier may now be possible thanks to a $489,000 grant from the Heising-Simons Foundation to a team of Penn State researchers to launch a feasibility study.
This funding will allow members of the College of Earth and Mineral Sciences and College of Engineering to map out a plan for installing a network of seismometers throughout the glacier, creating the most detailed view of the ice below to date.
If successful, phase two of this research will use state-of-the-art surveying and seismic techniques to quantify the dynamical behavior of ice as the glacier splits.
The Greenland Ice Sheet plays an important role in global sea-level change in a warming world by releasing increasing amounts of freshwater into the ocean.
Installing seismometers and collecting the data pose several challenges that prompted the feasibility study. The glacier is in a remote location only accessible by helicopter and is difficult to traverse because of its aggressive topography. That poses problems with installing and monitoring the devices.
To create devices capable of delivering vast amounts of data using limited battery power, researchers will fly drones overhead to collect the data instead of relying on satellites, which strain bandwidth and battery resources.
The sensors, called geoPebbles, measure vibrations in the ground to detect the motion of the ice below. Penn State researchers Sridhar Anandakrishnan and Sven Bilen, of the College of Engineering, designed them using National Science Foundation funding. A network of this many sensors can create a high-resolution image of the seismology of the glacier. Coupling this data with GPS and aerial imagery, researchers said, will hopefully characterize how the glacier is fracturing and lend insight into the effects and implications of that fracturing.
"The high resolution of data created by this many sensors has never been done at this glacier," said Anandakrishnan, professor of geosciences. "It's very ambitious. It's very similar to other experiments, but the scale is very different. This is a very dynamic glacier. It's moving fast. Pieces of it are breaking up, and we want to better understand this."
Anandakrishnan, who frequently works in Greenland and Antarctica, said there are already dozens of seismometers on Greenland, but nothing at this resolution.
"Our idea was to focus on a single glacier — a small area that's about 6 to 9 miles in size — and put lots and lots of instruments in that area," Anandakrishnan said. "Rather than learn about Greenland as a whole, which is what this larger network does, we want to focus on this one glacier and study it intensively. This will allow us to characterize the glacier in a comprehensive way."
Anandakrishnan said these single glaciers have global implications and can affect a host of areas, including severe weather events and sea level rise.
If this drone-based technique works, it could be used in a number of other key outlet fjords in Greenland, and would eventually allow for an even more comprehensive understanding
of ice fracturing. Jack Langelaan, associate professor of aerospace engineering, College of Engineering, is developing the drones needed to carry out this work.
"The Arctic is one of the places that is warming most rapidly," Anandakrishnan said. "The ice in Greenland is melting faster than in other Arctic areas. The sea ice is not as extensive or thick as it's been in the past. The conditions of the ocean are changing rapidly. Even though this is in the far north, because of the way water and the atmosphere circulates, it has connections to the rest of the world. Sea level change we see on the eastern U.S. coast is affected by these circulations in the north and by the size of the glaciers and the speed at which they are melting in Greenland."