A team of researchers has pinned an enigmatic glacial retreat on soot lofted into the atmosphere during Europe's industrialization.
The Industrial Revolution could be to blame for an Alpine glacial retreat that is inconsistent with the Little Ice Age conditions during which it took place, according to a new paper published in the journal Proceedings of the National Academy of Sciences.
A team of researchers has now pinned the perplexing glacial retreat on soot buoyed into the atmosphere as Europe chugged into its Industrial Age. The find offers a possible solution to a paradox in climate science: how could the Alpine glacier have receded when the European environment, at the time cold and wet, was primed for glacial expansion?
That enigma begins around 1860 in the snow-caked Alps. At about that time, the glaciers that gloss the European mountain range began to roll back at an average of nearly 0.6 miles each year, reaching the smallest range since about 500 years prior.
“This was an abrupt change,” says Thomas Painter, a researcher at NASA's Jet Propulsion Laboratory and the lead scientist on the paper.
But that glacial change was not mirrored in any such change in alpine conditions: “There was no abrupt change in precipitation. And there was no abrupt increase in temperature,” says Dr. Painter.
In fact, climate records suggest that the glaciers across Europe should have been advancing at that time. In 1860, the world was just rolling off what scientists have termed a Little Ice Age, which beginning about 1550 plunked medieval Europe into a cold spell some 300 years long. And it was not until about 1910 that the continent’s climate began to warm enough to suggest glacial shrinkage.
“That left us with what is often called the paradox of the Little Ice Age,” says Painter.
So, how did a glacier recede during an ice age, even if it was just a “little” one?