Scientists: Arctic warming increasing

BOULDER, Colo., Sept. 4 (UPI) -- Sediment cores show the Arctic has been warmer during the past decade than during any 10-year period in the last 2,000 years, scientists said.

"The study provides a clear example of how increased greenhouse gases are now changing our climate," said Caspar Ammann of the National Center for Atmospheric Research in Boulder, Colo.

Ammann and his team studied sediment cores from lakes, tree rings and ice cores, all of which showed the Arctic has been warming since about 1850 -- the beginning of the Industrial Age -- as greenhouse gas emissions increased, The San Francisco Chronicle reported Friday.

The seven-year study involving seven major research institutions in three countries was a "heroic effort" that bolstered global warming theory, said Stephen Schneider, a Stanford University climate expert who was not involved in the study.

New photos released by the U.S. Geological Survey also show at least 1,975 of the Arctic's 2,000 glaciers are shrinking more rapidly than ever, the Chronicle reported.