10/26/2009

Recent Arctic Warming Reverses Long-Term Cooling Trend

Summary

The climate and environment of the Arctic have changed drastically in recent centuries. New DOE research has synthesized 2000 years of proxy data (data gathered from natural recorders of climate variability such as tree rings, ice cores, historical data, etc.) from lakes above 60° N latitude with complementary ice core and tree ring records, to create an Arctic paleoclimate reconstruction with a 10-year resolution. This period began with a gradual cooling trend but by the beginning of the 20th century temperatures began to increase rapidly. The long-term Arctic cooling is consistent with a reduction in total summer solar radiation caused by changes in Earth’s orbit, while the rapid and large warming during the past century is consistent with the human-caused warming.

References

Kaufman, D.S., D. P. Schneider, N. P. McKay, C. M. Ammann, R.S. Bradley, K.R. Briffa, G.H. Miller, B.L. Otto-Bleisner, J.T. Overpeck, B.M Vinther and JOPL-SI authors, 2009. Recent Warming Reverses Long-Term Arctic Cooling. Science, 325, 1236-1239.