Arctic sea ice is disappearing on a pace and magnitude unlike anything the Earth has experienced in the past 1,450 years, according to a Canadian-led study published in the leading science journal Nature.
The amount of sea ice in the Arctic has been declining continuously for the past four to five decades — and is now some two-million square kilometres smaller in area than it was in the late 20th century. But until this study, spearheaded by researchers Christian Zdanowicz and David Fisher from the Geological Survey of Canada, it remained unclear whether these losses of recent decades were out of line with natural fluctuations of the past.
After reconstructing the extent of summer sea ice over the centuries, the authors found that recent decades' losses are of a greater duration and magnitude than at any other period during the past 1,450 years — a finding consistent with the theory that humans are changing the earth's climate in dramatic fashion.
Access the original article published in Nature.
Adapted from news article published by Amy Chung and Randy Boswell for the Vancouver Sun, 24 November 2011.
Photo caption: Arctic Sea north of Svalbard, credit Peter Prokosch.