New CU-led study may answer long-standing questions about enigmatic Little Ice Age
http://www.colorado.edu/news/releases/2012/01/30/new-cu-led-study-may-answer-long-standing-questions-about-enigmatic-little[font face=Times, Serif][font size=5]New CU-led study may answer long-standing questions about enigmatic Little Ice Age[/font]
January 30, 2012
[font size=3]A new University of Colorado Boulder-led study appears to answer contentious questions about the onset and cause of Earths Little Ice Age, a period of cooling temperatures that began after the Middle Ages and lasted into the late 19th century.
According to the new study, the Little Ice Age began abruptly between A.D. 1275 and 1300, triggered by repeated, explosive volcanism and sustained by a self- perpetuating sea ice-ocean feedback system in the North Atlantic Ocean, according to CU-Boulder Professor Gifford Miller, who led the study. The primary evidence comes from radiocarbon dates from dead vegetation emerging from rapidly melting icecaps on Baffin Island in the Canadian Arctic, combined with ice and sediment core data from the poles and Iceland and from sea ice climate model simulations, said Miller.
While scientific estimates regarding the onset of the Little Ice Age range from the 13th century to the 16th century, there is little consensus, said Miller. There is evidence the Little Ice Age affected places as far away as South America and China, although it was particularly evident in northern Europe. Advancing glaciers in mountain valleys destroyed towns, and famous paintings from the period depict people ice skating on the Thames River in London and canals in the Netherlands, waterways that were ice-free in winter before and after the Little Ice Age.
The dominant way scientists have defined the Little Ice Age is by the expansion of big valley glaciers in the Alps and in Norway, said Miller. But the time it took for European glaciers to advance far enough to demolish villages would have been long after the onset of the cold period, said Miller, a fellow at CUs Institute of Arctic and Alpine Research.
[/font][/font]
http://dx.doi.org/10.1029/2011GL050168