AGU: Geophysical Research Letters

 

Editors' Highlight

Plants emerging from beneath melting Canadian ice caps: A millennial perspective on Arctic warming

Human-induced climate change has warmed global temperatures for at least the past 50 years, leaving Arctic areas particularly vulnerable. Noting that the plateau ice caps of Baffin Island, Arctic Canada, are sensitive indicators of climate, Anderson et al. (2008) analyzed aerial imagery and found that ice cover has diminished by more than 50% since 1958. Linear projections suggest that all ice caps on the island's plateau will disappear by 2070 A.D. The authors radiocarbon-dated dead vegetation emerging beneath receding ice margins and found that ice caps are smaller now than since at least 350 A.D. Cosmogenic radiocarbon accumulating in exposed rocks, which reveals their postglacial exposure history, shows that the plateau supported ice caps for most of the past 2800 years, accentuating the anomalous nature of twentieth-century warmth. Periods of widespread ice cap expansion during the Little Ice Age coincide with peak levels of volcanic aerosols in the stratosphere and reduced solar luminosity, suggesting a trigger mechanism for the Little Ice Age. The current warming exceeds any sustained warm episode in this area for at least the past 1600 years.

View abstract

View full article (Subscription required)