The possibility that global warming might contribute to Arctic development isn’t anything new. America’s first European visitors, the Vikings, were able to reach and colonize the northernmost reaches of the continent due to the lack of sea ice covering the Arctic Ocean during Medieval times when the earth was going through a warming period.

The Viking era came well before the Industrial Revolution — when humans began burning large amounts of fossil fuels which some scientists say causes global warming — and suggests that there are strong natural climate forces that have a profound effect on the extent of Arctic sea ice coverage. However, this is not a new theory — it was discussed as far back as the 19th century.

According to an 1887 newspaper article entitled “Variations in Climate,” Scandinavian Vikings were able to sail through the Arctic Ocean and establish colonies in the “highest north latitude” of Greenland and North America centuries before the arrival of Christopher Columbus. These colonies, however, were abandoned by the Vikings due to “the increasing cold.”

“On the contrary, the formation of ice increases annually if the winters are strongly cold, long and dark,” wrote Alexander Beck in 1887. “The reverse of that state of things is found by calculations for the year 1122 A.D., and it is precisely at that time we find the Danes and other Scandinavian nations going through the Arctic open seas.”

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