As Hurricane Gonzalo takes aim at the Island, a yellow undersea glider named Anna will swim straight into the storm, piloted by a Bermuda Institute for Ocean Sciences (BIOS) scientist taking advantage of a rare opportunity to learn what happens below the ocean surface during a hurricane.

“This is one of the holy grails of glider science, to catch the passage of a major hurricane in the open ocean,” said Ruth Curry, a physical oceanographer who deployed the glider on Tuesday morning about five miles east of St. David’s Head.

Past observations of how these storms affect the upper ocean have come almost exclusively from instruments on moorings that happen to be in the storm’s path. Anna can travel thousands of miles through the ocean on a single journey, providing a detailed picture of storm impacts.

The glider dives from the sea surface to 1,000 meters depth (3,000 feet), covering about 15 miles per day and communicating with shore-based scientists via satellite when at the surface.

Ms Curry expects the data gathered to include recordings about the waters around Bermuda, which will cool off by several degrees as Gonzalo’s winds draw heat from the ocean into the atmosphere, and create strong currents 50 to 60 feet below the sea surface.