The Viking people suddenly vanished from Greenland in the mid-15th century, about 400 years after arriving in the region.
The reason why the Vikings abandoned a successful settlement remains a mystery that historians have yet to explain.
Rising sea levels were a factor in the Vikings’ departure.
Theories proposed include drought, temperature changes, social unrest, and overhunting of walrus ivory, a luxury item highly prized in medieval Europe. These conditions may have made the Norse colonies in Greenland economically unsustainable.
Now, researchers from Harvard University and Pennsylvania State University have identified another significant factor that may explain why the Vikings left: rising sea levels.
The researchers utilized computer models based on geological and climatic records. They found that sea levels could rise by up to 3 meters (9.8 feet) during the four centuries that the Norse occupied the Viking settlement established in Greenland in 985 AD.
The researchers calculated that 204 square kilometers (79 square miles) of land would be flooded during the time the settlement was occupied. This phenomenon made Norse communities more vulnerable to storms and coastal erosion, while also increasing the risk of losing fertile lowland.
The loss of habitable land would combine with a trend of transitioning from warmer to cooler, drier conditions in Europe. This situation eventually led to what is known as the Little Ice Age, which began around 1250 AD. A detailed study of these findings has been published in the scientific journal PNAS.
“Rising sea levels are an indispensable factor in the story of the Vikings,” said Richard Alley, co-author of the study and a Professor of Geosciences at Penn State University.
The researchers also noted that analyses of remains from churchyards and animal carcasses from refuse piles indicate that over time, the diet of Viking settlers shifted from terrestrial foods like livestock to marine resources such as fish and seals. This change may have been due to the loss of arable land.
According to the researchers, the idea that sea levels would rise as temperatures fell is somewhat counterintuitive. Generally, cooler global temperatures are associated with declining sea levels.
However, the Earth’s oceans do not behave like a bathtub. The study notes that changes in sea levels do not have the same effects across all regions.
