30 June 2011

Abrupt climate change doomed Norse settlements: Study

Interest continues to develop for a sudden climatic change leading to the destruction of the two medieval Viking settlements on Greenland as the scientific community gears-up for another summer of archaeological work in the far north.




                                                                       Photograph by: File photo, Postmedia News

New scientific evidence supporting a long-standing theory that abrupt climate change probably doomed Greenland's Norse settlements about 650 years ago may also explain why most Canadians today are not speaking Danish and celebrating their Viking ancestry.

The study by a group of researchers from Denmark, Germany and Norway used samples of marine sediment from Greenland's west coast to reconstruct a picture of the giant island's climate over the past 1,500 years. Their findings showed that when Scandinavian settlers led by Eric the Red first established colonies on Greenland in 985, the west coast around present-day Disko Bay — located just 400 kilometres east of Baffin Island across the Davis Strait — was relatively warm and conducive to the farming life the settlers favoured.

It was during that early era of Norse settlement in Greenland that Viking explorers — most famously Eric's son, Leif Ericsson — are known to have become the first Europeans to reach the Americas.

L'Anse aux Meadows, at the northern tip of Newfoundland, was the site of a Norse settlement established around 1,000 but abandoned shortly after — primarily, scholars believe, because of attacks by hostile aboriginal tribes known as "skraelings" to Ericsson and his fellow adventurers.

The Norse continued to inhabit their Greenland settlements for at least 350 more years, with evidence documented from Baffin Island by Canadian archaeologist Pat Sutherland suggesting sporadic contact between Greenlandic Norse traders and the Dorset culture, ancient aboriginals who were later overrun — probably before 1400 — by the eastward-migrating Thule ancestors of modern Inuit.

But around that same time, the European researchers have concluded in a study published in the journal Boreas, a prolonged stretch of cold weather on Greenland appears to have led to the demise of the Norse settlements there. And any chance of a renewed effort by the Scandinavian seafarers to colonize Canada disappeared with them.

That left the next, and enduring, wave of European settlement in North America to French and English colonists after explorer John Cabot reached Newfoundland in 1497.

"Our study shows a major shift towards cooler conditions and extensive sea-ice which coincides with the estimated time for the collapse of the western settlement in AD 1350," University of Copenhagen geologist Sofia Ribeiro said in a summary of the new study.

"The Norse were proud of being Europeans, farmers and Christians, and never adopted the hunting and survival techniques of the Inuit, so these temperature shifts would have caused significant problems for the colonists and their livestock."

Ribeiro cautioned that "we cannot attribute the end of the Norse civilization to a single factor," but noted that "there is enough evidence to suggest that climate change played a major role in determining its collapse."

The harsher climate in Greenland would have made "farming and cattle production increasingly difficult" at the same time that increased sea ice "prevented navigation and trading with Europe," she stated.

Ribeiro told Postmedia News that "what happened to the Norse after 1350 is a mystery."

But she noted that in both Greenland and nearby Newfoundland, "there were no specially favourable conditions for the Norse to settle there during medieval times."

The Boreas study pointing to the onset of severe cooling in Greenland at the end of the Norse habitation supports recent research published by scientists at Brown University in Rhode Island in the Proceedings of the National Academy of Sciences.

After probing sediments from two lakes near Greenland's west coast, they also concluded that abrupt climate cooling preceded the disappearance of the Norse settlements in the region.


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