Operation IceBridge is a project that sends flights over both polar regions to photograph and map land and sea ice. And images that were taken during a flight on April 14 over the Beaufort Sea, 50 miles northwest of the Mackenzie River Delta, showed a series of unusual shapes in the sea ice.
“We saw these sorta-circular features only for a few minutes today,” mission scientist John Sonntag wrote from the field, per NASA. “I don’t recall seeing this sort of thing elsewhere.”
NASA also released an image with the main features labeled:
NASA said some of the features had an easy explanation: The ice in the area was young and thin. When these types of floes collide, “finger rafting” ― the zipper-like feature at the top right ― will form. However, the agency conceded that the holes were little harder to explain, and no one could quite say for sure what caused them.
“The encircling features may be due to waves of water washing out over the snow and ice when the seals surface,” Walt Meier, a scientist at the National Snow and Ice Data Center, said in a news release. “Or it could be a sort of drainage feature that results from when the hole is made in the ice.”
Other experts contacted by NASA agreed that the features could be breathing holes made by seals as well as other possibilities, including warm groundwater flowing out to the sea ice from inland mountains.