A remotely operated submersible vehicle called Nereid Under Ice (NUI) is about to take part in a mission to explore the glaciers of Greenland.
Scheduled for launch in 2023, the mission led by researchers at the University of Texas at Austin will be the first time the Greenland glaciers – which make up the world’s second-largest ice cap – will be seen up close underwater. .
Designed by project partner, the Woods Hole Oceanographic Institution (WHOI), NUI will encounter icebergs and eddies as they approach glaciers and return with data and samples of the underwater environment.
Scientists will mainly focus on the sand walls (moraines) that reinforce glaciers and are believed to naturally stabilize the ice sheet. What they learn will reveal what is reinforcing glaciers across the entire Greenland Ice Sheet, which could lead to more accurate model projections for future sea level rise.
“The big uncertainty about Greenland’s contribution to sea level rise is how fast the ice sheet will lose mass,” said Ginny Catania, a professor at UT’s Jackson School of Geosciences. , who leads the trip. “We know how much sea level is stored in the ice sheet, we know the climate is warming and changing the ice sheet, but what we don’t know is how fast these glaciers will contribute to the sea level rise.”
Funded by the WM Keck Foundation, the mission will study three glaciers in West Greenland that are in the path of warming Atlantic waters but have reacted in different ways. Since 2000, Kangilliup Sermia has experienced only a minor setback, Umiammakku Sermiat retreated quickly before leveling off again in 2009, and Kangerlussuup Sermia remained largely unaffected by warming.
“They provide a good test case for ideas about what builds moraines and how those processes might vary from place to place,” Catania said in a statement.
NUI will navigate underwater to the face of each glacier, mapping the topography of the sea floor as it goes. Once at its target site, operators aboard a nearby support vessel will remotely guide the robot’s manipulator arm to retrieve sediment cores from glacier moraines. The vehicle will also collect samples of the massive plumes of sediment thrown up from under the glaciers.
According to project co-lead Mike Jakuba, senior engineer at WHOI, the robot was designed with layers of built-in redundancy, including multiple thrusters, batteries and navigation systems to allow it to operate in harsh conditions away from its vessel. Support.
Its main communications link is a 10-mile-long optical fiber connecting NUI to its support vessel, allowing operators to control its cameras and arm. The robot can still be piloted using underwater acoustics if the fiber breaks and automatically returns to a pickup point if all communications fail.
Jakuba said the mission will help scientists understand the critical link between the world’s oceans and ice sheets.
“With NUI, the vision from the beginning was to provide a system that would project human presence into environments like this that require better access if we are to better understand how the planet is changing,” he said.
Partner institutions include the University of Idaho, University of Florida, and the University of Texas Institute of Geophysics (UTIG).
“This is high-risk and highly rewarding science, but it’s exactly the kind of bold step needed to tackle pressing and societal relevant questions about climate change and geohazards,” Demian said. Saffer, director of UTIG. “If successful, it could transform our understanding of sea level rise.