Unusual volcanic episode rapidly triggered Little Ice Age, researchers find
30 January 2012
AGU Release No. 12-05
For Immediate Release
WASHINGTON, DC?New evidence from northern ice sheets suggests that volcanic eruptions triggered the multiple-century cool spell known as the Little Ice Age, and pinpoints the start of the climate shift to the final decades of the 13th century. Researchers have long known that the Little Ice Age began sometime after the Middle Ages and lasted into the late 19th century. But, estimates of its onset have ranged from the 13th to the 16th century.
According to the new study, the Little Ice Age began abruptly between 1275 and 1300 A.D., triggered by repeated, explosive volcanism and sustained by a self-perpetuating sea ice-ocean feedback in the North Atlantic Ocean. The primary evidence comes from radiocarbon dates from dead vegetation emerging from rapidly melting icecaps on Baffin Island, combined with ice and sediment core data from the poles and Iceland, and from sea-ice climate model simulations, said Gifford Miller, a geological sciences professor at the University of Colorado, Boulder (CU-Boulder), who led the study....
