The hull strength is produced almost entirely from a sophisticated internal support structure that features canted ribs for approximately the forward two-thirds of the ship's frame.

Polar Sea's hull shape is designed to maximize icebreaking by efficiently combining the forces of the ship's forward motion, the downward pull of gravity on the bow, and the upward push of the inherent buoyancy of the stern.

This design does not use sharp edges or hammer-like blows to cut or break the ice, as the round bow and massive weight are sufficient.

[8] The J-shaped cranes and work areas near the stern and port side of ship give scientists the capability to do at-sea studies in the fields of geology, vulcanology, oceanography, sea-ice physics and other disciplines.

In 1985, Polar Sea triggered a diplomatic event by navigating the Northwest Passage from Greenland to Alaska without authorization from the Canadian government.

It was the United States' position that the Northwest Passage was an international strait open to shipping and it sought only to notify Canada rather than ask for permission.

The U.S. never recognized Canada's claim over the Northwest passage but nevertheless, the two countries reached an agreement two years later which stipulated that in the future, the U.S. would ask permission before navigating the disputed waters.

[12] In 2011 the Coast Guard slated Polar Sea for demolition in 2012,[13] but the scrapping of the 35-year-old icebreaker was postponed by Congress for at least six months in June.

[14] As of September 25, 2022[update] the laid up ship was still in limbo alongside a pier at the Coast Guard Station on Elliott Bay, Seattle.