The ice core revealed that summer temperatures got cooler and winter temperatures warmed up between about 8,000 and 5,000 years ago, and that reduction in extremes helped make Transylvania more palatable to Neolithic farmers.
“There were cold winters, hot summers and wet. That means the rivers were very active and there was a lot of flooding,” Persoiu said. So people migrating up the Balkan Peninsula shifted toward Western Europe. But when the climate shifted toward a more Mediterranean influence, warmer, drier winters allowed for stable agriculture, bringing people to the area, he said.
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While the Scarisoara ice core has given scientists a window into the Holocene past, its applications for the future have been limited by a very modern problem: climate change. The top layer of the glacier has been melting away, erasing whatever data it might have held since the late 19th century, Persoiu said.
“The age of the ice at the uppermost level is something like 1860 or 1880,” he said. “We lost the last 150 years of ice, so we cannot compare it to present-day conditions … All over the planet, caves of ice are disappearing quite fast.”
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