Historic Arctic Ocean Crossing

Two icebreaking ships have become the first surface ships to traverse the Canada Basin, the ice-covered sea between Alaska and the North Pole.

The Swedish vessel Oden and the United States Coast Guard's Healy, completed the historic south-to-north trek in September as part of an expedition to explore the region's marine environment. The pair conducted studies of the regions ocean properties as part of an effort to evaluate recent changes in ocean climate and global change studies.

Submarines have crossed the central Arctic Ocean region before, but heavy concentrations of floating sea ice--in some areas as thick as 10-feet--are dangerous for most surface ships.

Part of the reason the Canada Basin surface crossing was possible now was because the ice cover over much of the Arctic Ocean has thinned by nearly 40 percent in recent decades, according to ship researchers.

But even thinned, the ice still proved a major obstacle at times. The two ships sometimes had to work in tandem to cut through the ice and forge a passage to the North Pole, which they reached on September 12 at 9 am.

--Ker Than

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Credit:  Scripps Institution of Oceanography