"Robotic Explorers: Unveiling the Secrets Beneath the Antarctic Ice Shelf"

A fleet of underwater robot probes is being designed by engineers who specialize in building NASA spacecraft to explore faraway worlds. Their goal is to measure how quickly huge ice sheets around Antarctica are melting due to climate change and what that means for rising sea levels. A U.S. submarine was used to test a prototype of the submersible vehicles that are being developed by NASA's Jet Propulsion Laboratory near Los Angeles. It was deployed in March beneath the frozen Beaufort Sea, north of Alaska, to a Navy laboratory camp in the Arctic. In a summary that was made available on the website of NASA on Thursday, Paul Glick, a principal investigator for the IceNode project and an engineer at JPL Robotics, stated, "These robots are a platform to bring science instruments to the hardest-to-reach locations on Earth."

 

The tests are pointed toward giving more precise information checking the rate at which warming sea water around Antarctica is softening the mainland's beach front ice, permitting researchers to further develop PC models to anticipate future ocean level ascent. Nearly 1,500 academics and researchers gathered in southern Chile this week for the 11th conference of the Scientific Committee on Antarctica Research to discuss the fate of the largest ice sheet in the world. According to a JPL analysis that was published in 2022, Antarctica's ice shelf had lost about 12 trillion tons of mass since 1997 due to thinning and crumbling, which was twice as much as previous estimates had predicted. Whenever liquefied totally, as indicated by NASA, the deficiency of the landmass' ice rack would raise worldwide ocean levels by an expected 200 feet (60 meters).

 

Ice shelves are floating slabs of frozen freshwater that extend miles from the land into the sea. They take thousands of years to form and function as enormous buttresses that prevent glaciers from easily sliding into the ocean. Satellite images have revealed that the outer layer is "calving" off into icebergs at a rate that is higher than what nature can do to replenish shelf growth. With the submersible IceNode probes, scientists hope to better understand how rising ocean temperatures are simultaneously eroding the shelves below. Boreholes in the ice or ships at sea would be used to release the 10 inches (25 cm)-diameter, 8 feet (2.4 meters)-long cylindrical vehicles.

The robot probes would use special software guidance to drift in currents to reach "grounding zones," where the frozen freshwater shelf meets the ocean saltwater and land, despite not having any form of propulsion. Even satellite signals cannot enter these cavities. A JPL climate scientist named Ian Fenty stated, "The goal is getting data directly at the ice-ocean melting interface." By releasing three-pronged "landing gear" sprung from one end of the vehicle, the submersibles would drop their ballast and float upwards to affix themselves to the underside of the ice shelf when they reached their targets.

 

After that, the IceNodes would continuously record data from beneath the ice for up to a year, including seasonal variations, before releasing themselves to drift back to the open seas and send readings via satellite. Satellite altimeters that measured the fluctuating height of the ice from above were previously used to document the thinning of the ice shelf. An IceNode prototype plunged 100 meters (330 feet) into the ocean as part of the March field test to collect salinity, temperature, and flow data. Past tests were led in California's Monterey Sound and underneath the frozen winter surface of Lake Unrivaled, off Michigan's upper landmass. Glick stated that although "we have more development and testing to go" before determining a timeline for full-scale deployment, scientists ultimately believe that 10 probes would be ideal for collecting data from a single ice shelf cavity.