IceNode: A Buoyant Vehicle for Acquiring Well-Distributed, Long-Duration Melt Rate Measurements under Ice Shelves
Oceans Conference Record (IEEE)
Antarctic ice shelves buttress the Antarctic Ice Sheet from sliding into the ocean and significantly raising global sea level. However, the accelerating dynamics of ice shelf melt in a warming environment are poorly understood, and the collapse of Antarctic ice shelves remains one of the largest sources of uncertainty in global sea level rise projections. The cavities below Antarctic ice shelves are notoriously difficult to access, making model-based hypotheses about the relationship between ocean warming and greater ice shelf melting difficult to verify because of a lack of in-situ data to constrain model parameters and examine key assumptions. We present early progress on IceNode, a novel vehicle under development at the NASA Jet Propulsion Laboratory designed to acquire well-distributed, concurrent, long-duration melt rate measurements under ice shelves. IceNodes are deployed as an array from a ship at the shelf edge, and use variable buoyancy to ride melt-driven exchange currents far into the cavity. Once underneath their target landing area, they release a ballast weight to gain high positive buoyancy and attach to the underside of the ice shelf, where they acquire in-situ measurements of basal melt rate directly at the ice-ocean interface for a year or more. Finally, IceNodes detach from their landing structure and use variable buoyancy to ride melt-driven exchange currents back to open water, where they surface and transmit their mission data home. IceNodes are designed to be relatively low-cost, expendable, and have simple logistics, enabling scientists to deploy scalable arrays that acquire simultaneous, distributed measurements of co-varying ice shelf melt and ocean conditions over large spatial areas, thereby providing an unprecedented view of ice shelf melt rate variability and its drivers.
National Aeronautics and Space Administration
Autonomous, Buoyant lander, Climate change, Grounding zone, Ice shelf, Ice shelves, Icenode, Melt, Oceanic instrumentation, Oceanography, Profiling float, Robotics, Sea level rise, Sensors, Underwater vehicles, Vehicle design
Moss Landing Marine Laboratories; Research Foundation
Evan Bock Clark, Andrew Branch, Rebecca Castano, Ian Fenty, Christine Gebara, Ara Kourchians, Daniel Limonadi, Gauri Madhok, Patrick McGarey, Flora Mechentel, Kelly Nguyen, Tyler Okamoto, Eric Rignot, Federico Rossi, Brendan Santos, Justin Schachter, Michael Schodlok, Dane Schoelen, Timothy Stanton, Joshua Vander Hook, Ben Wolsieffer, and Xavier Zapien. "IceNode: A Buoyant Vehicle for Acquiring Well-Distributed, Long-Duration Melt Rate Measurements under Ice Shelves" Oceans Conference Record (IEEE) (2021). https://doi.org/10.23919/OCEANS44145.2021.9705733