June 22, 2006

Running Time: 01:09:12

Format: RealAudio (Requires free RealPlayer)

There is sufficient evidence from tree rings, retreating glaciers, and other "proxies" to say with confidence that the last few decades of the 20th century were warmer than any comparable period in the last 400 years, according to a new National Research Council report. There is less confidence in reconstructions of surface temperatures from 1600 back to A.D. 900, and very little confidence in findings on average temperatures before then.

Committee Gerald R. North, Distinguished Professor of Meteorology and Oceanography and Harold J. Haynes Endowed Chair in Geosciences, Texas A&M University, College Station