Thwaites, a notoriously unstable glacier in western Antarctica, is cracking and disintegrating, spelling bad news for sea level rise across the globe. Efforts are afoot to understand the geometry and chemistry of Thwaites, which is about the size of Florida, in order to gauge the impact that warming waters and climate change may have on it.
An 11-foot tube-like underwater robot called Icefin is offering us a detailed look deep under the ice at how the vulnerable ice shelf in Antarctica is melting. By way of two papers published this week in the journal Nature, Icefin has been providing pertinent details regarding the conditions beneath the freezing waters.
The torpedo-like Icefin was first developed at Georgia Tech, and the first prototype of the robot dates back to 2014. But it has since found a new home at Cornell University. This robot is capable of characterizing below-ice environments using the suite of sensors that it carries. It comes equipped with HD cameras, laser ranging systems, sonar, doppler current profilers, single beam altimeters (to measure distance), and instruments for measuring salinity, temperature, dissolved oxygen, pH, and organic matter. Its range is impressive: It can go down to depths of 3,280 feet and squeeze through narrow cavities in the ice shelf.
Since Icefin is modular, it can be broken down, customized, and reassembled according to the needs of the mission. Researchers can remotely control Icefin’s trajectory, or let it set off on its own.
Icefin isn’t alone in these cold waters. Its journey is part of the International Thwaites Glacier Collaboration (ITGC), which includes other radars, sensors, and vehicles like Boaty McBoatface.
In 2020, through a nearly 2,000-foot-deep borehole drilled in the ice, Icefin ventured out across the ocean to the critical point where the Thwaites Glacier joins the Amundsen Sea and the ice starts to float. Data gathered by Icefin, and analyzed by human researchers, showed that the glacier had retreated up the ocean floor, thinning at the base, and melting outwards quickly. Additionally, the shapes of certain crevasses in the ice are helping funnel in warm ocean currents, making sections of the glacier melt faster than previously expected.
These new insights, as foreboding as they are, may improve older models that have been used to predict the changes in Thwaites, and in the rates of possible sea level rise if it collapses.
“Icefin is collecting data as close to the ice as possible in locations no other tool can currently reach,” Peter Washam, a research scientist from Cornell University who led analysis of Icefin data used to calculate melt rates, said in a press release. “It’s showing us that this system is very complex and requires a rethinking of how the ocean is melting the ice, especially in a location like Thwaites.”
Outside of Thwaites, you can find Icefin monitoring the ecosystems within ice-oceans around Antarctica’s McMurdo research station, or helping astrobiologists understand how life came to be in ocean worlds and their biospheres.
Learn more about Icefin below: