Open Polar Sea

The Open Polar Sea was a hypothesized ice-free ocean surrounding the North Pole. This unproven (and eventually disproved) theory was once so widely believed that many exploring expeditions used it as justification for attempts to reach the North Pole by sea, or to find a navigable sea route between Europe and the Pacific across the North Pole.

The theory that the north polar region might be a practical sea route goes back to at least the 16th century when it was suggested by Robert Thorne. Explorers William Barents and Henry Hudson also believed in the Open Polar Sea. For a time, the theory was put aside due to the practical experience of navigators who encountered impenetrable ice as they went north. But the idea was revived again in the mid-19th century by theoretical geographers such as Matthew F. Maury and August Petermann. At this time, interest in polar exploration was high due to the search for John Franklin's missing expedition, and many would-be polar explorers took up the theory, including Elisha Kent Kane, Dr. Isaac Israel Hayes, and George Washington De Long. It was believed that once a ship broke through the regions of thick ice that had stopped previous explorers, a temperate sea would be found beyond it.

Although today we know that the North Pole was covered with thick ice for much of the period, the theory of the Open Polar Sea was popular in the 16th–19th centuries and many arguments were made to justify its existence:

The Open Polar Sea theory was debunked gradually by the failure of the expeditions in the 1810s through the 1880s to navigate the polar sea. Reports of open water by earlier explorers, such as Elisha Kent Kane and Isaac Israel Hayes, fueled optimism in the theory in the 1850s and 1860s. Support faded when George W. De Long sailed USS Jeannette into the Bering Strait hoping to find an open 'gateway' to the North Pole and was met by a sea of ice. After a long drift, pack ice crushed the Jeannette and her survivors returned home with first hand accounts of an ice-covered polar sea. Other explorers such as British explorer George Nares confirmed this. By the time Fridtjof Nansen and Otto Sverdrup drifted through the polar ice pack in Fram in 1893–1895, the Open Polar Sea theory was defunct.

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