Last big icebreaker leaves California after repairs; supporters call for rebuilding ice fleet

In this Monday Nov. 10, 2014 photo, a dry dock containing the icebreaker USS Polar Star is flooded with water on Mare Island in Vallejo, Calif. The United States' last vessel capable of breaking through the heaviest ice of the Arctic Circle, and resupplying the U.S. polar research station there, is scheduled to leave San Francisco Bay on Tuesday, Nov. 11, 2014, after repairs meant to help the vessel limp along another few years. While Russia and China have dozens of icebreakers, opposition in Congress to funding means the U.S. has just one heavy-duty one, already a decade past its decommissioning date. (AP Photo/U.S. Coast Guard) (The Associated Press)

FILE - In this March 10, 2010, file photo, a 25-foot harbor patrol boat passes by the 399-foot U.S. Coast Guard icebreaker Polar Star as it sits moored at a dock in Seattle. While Russia and China have dozens of icebreakers, opposition in Congress to funding means the U.S. has just one heavy-duty one, already a decade past its decommissioning date. (AP Photo/Elaine Thompson, File) (The Associated Press)

SAN FRANCISCO – The U.S. Coast Guard's last heavy icebreaker is leaving California after repairs to postpone its already overdue retirement.

The Polar Star is slated to sail away from the former Mare Island Naval Shipyard on Tuesday. Crews there carried out the latest maintenance to extend the life of the 38-year-old vessel.

Polar Star Capt. Matt Walker says the vessel is the only U.S. icebreaker still capable of breaking through the heavy ice of the Antarctic. The Polar Star in coming months will carry out the annual resupply of two U.S. research stations in Antarctica. Scientists there study the 1.5 million-year-old ice to learn the secrets of weather and climate change.

The Polar Star is eight years past its scheduled retirement date. Congress, the Obama administration and the Coast Guard have yet to agree on any possible funding for a replacement.