More than merely cracks in the ice, crevasses play an important role in circulating seawater beneath Antarctic ice shelves, potentially influencing their stability, finds Cornell-led research based on first-of-its-kind exploration by an underwater robot. The remotely operated Icefin robot’s climb up and down a crevasse in the base of the Ross Ice Shelf produced the first 3D measurements of ocean conditions near where it meets the coastline, a critical juncture known as the grounding zone. The robotic survey revealed a new circulation pattern – a jet funneling water sideways through the crevasse – in addition to rising and sinking currents, and diverse ice formations shaped by shifting flows and temperatures. Included in the Cornell research team is Justin Lawrence, a visiting Ph.D. scholar from the School of Earth and Atmospheric Sciences.