Generating and synthesizing paleoclimate data to assess Arctic climate change

PAGES Working Group Meeting: Arctic Climate During the Last 2 Millennia; Boulder, Colorado, 8 March 2008; Climate change in the Arctic is amplified by albedo feedbacks involving snow and ice. Between the nineteenth and 21st centuries, warming in the Arctic was very likely double that for the globe (see Impacts of a Warming Arctic, Cambridge University Press, 2004). This trend appears to have further accelerated during the past decade as evidenced by both the dramatic decrease of summer sea ice cover and increased melt rates of glaciers. The limited instrumental record covering only the past ∼50 years severely limits our understanding of multidecadal and centennial spatial and temporal variability. It is therefore unclear if the increased rate of change is the result of superposition of the general warming trend on natural climate variability or if the Arctic system might have reached a tipping point. As the Arctic is home to the large ice mass of Greenland, it is therefore crucial for climate change research to improve our understanding of this sensitive region.