Photos: Lake Superior's annual ice-breaking ritual


The U.S. Coast Guard Cutter Alder breaks ice to create navigation lanes.
1 The U.S. Coast Guard cutter Alder breaks ice and creates navigation lanes for the opening of the maritime shipping season on Friday in the Duluth-Superior harbor, "taking all the bigger pieces of ice that we find, making them a little bit smaller, and just grooming a path, just like your cross country ski path," said Lt. Daniel Kubasch, the executive officer onboard. 
Chief Petty Officer Ben L'Allier directs navigation of the ice cutter.
2 Chief Petty Officer Ben L'Allier watches a monitor while helping direct navigation of the Alder Friday in the Duluth-Superior harbor. As the conning officer, he gives commands to the helmsman in order to keep the Alder in safe water, while still breaking ice that needs to be broken. 
The route through the Lake Superior ice and Mackinaw are visible.
3 The route through the Lake Superior ice left behind by U.S. Coast Guard cutters Alder and Mackinaw are visible Thursday just outside the Duluth Ship Canal. The cutters began ice-breaking operations in the Duluth-Superior harbor the next day.

Despite the balmy spring weather lately, Lake Superior still has a lot of ice. A few weeks ago, the lake was more than 90 percent covered in ice — the most it's had in the past five years.

That ice cover has dwindled now to less than 40 percent, but when the cutters began their work, there was still at least a foot of ice encasing the Duluth harbor.
 
The 1004-foot long American Spirit passes under the aerial lift bridge.
4 The 1,004-foot-long American Spirit passes under Duluth's Aerial Lift Bridge while departing the Duluth-Superior harbor Sunday. The ship was able to free itself and navigate the harbor thanks to the ice-breaking assistance of Coast Guard cutters Alder and Mackinaw.

There are still more than 15 miles of ice extending offshore from Duluth before ships hit open water on Lake Superior. The Alder and the Mackinaw cut lanes through the ice last week. But if ice breaks off the shore, it can clog up those paths they created.

"And now, the name of the game is don't break the shore ice," Kubasch said, "keep the ice on the shore as long as we can, keep the pass that we're opening — nice blue water — for as long as we can, and hopefully the rest of the ice just melts in place."
 
Chunks of ice as thick as a foot or more float by the ice cutter.
5 Chunks of ice as thick as a foot or more float by the Alder during ice-breaking operations Friday. The Alder slows when it hits solid ice. The ship's pointed bow rides up on top of the ice. But it's the weight of the ship — more than 2,100 tons — that crushes the ice.

"We're using our weight to ride up on it," Kubasch said, "and then our bow to compress it, and then our speed through the water to push it away."

Fissures and cracks extend from the ship, then the ice breaks apart into enormous plates.
 
Boatswain's Mate Casey Perez and Seaman Jillian Carlson
6 Boatswain's Mate Casey Perez, left, and Seaman Jillian Carlson are among a 30-member crew onboard the U.S. Coast Guard cutter Alder as it breaks ice and creates navigation lanes for the opening of the maritime shipping season in the Duluth-Superior harbor. 
The U.S. Coast Guard Cutter Alder approaches the aerial lift bridge.
7 The U.S. Coast Guard Cutter Alder approaches the aerial lift bridge to assist three ships that had left in the previous two days and ended up stuck in the Lake Superior ice Sunday. With the assistance of the Alder, the ships were freed and could continue onto their destinations. 
A shadow of the U.S. Coast Guard Cutter Alder sits on the ice.
8 The shadow of the U.S. Coast Guard cutter Alder sits on the ice of the Duluth-Superior harbor Friday during the ice-breaking operation that signals the start of spring. After cutting a wide highway through the ice the length of the harbor, the Alder then travels in circles, breaking up big areas in the ice so the ships can maneuver.

"When we're moving thousand-foot ships, they need lots of room to turn," said Kubasch. "Just like if you're driving your Geo Metro versus your Astro van." If ships don't have enough open water to turn, Kubasch said, they can get pinned between two pieces of ice.
 
The sun sets on Duluth's aerial lift bridge and the route left in the ice.
9 The sun sets on Duluth's Aerial Lift Bridge and the route left by U.S. Coast Guard cutters Alder and Mackinaw in Duluth.

After the Alder's successful day of breaking up ice Friday, three ships that left the harbor over the weekend got stuck in the ice outside Knife River. The Alder then made an unexpected trip up the shore Sunday morning to free them.

Two more ships are scheduled to navigate through the ice into the harbor Wednesday, including the 1,013-foot-long Paul R. Tregurtha headed to Duluth to pick up a load of coal.