US National Academies report says global warming real

The National Academies have released a report, no doubt to the considerable irritation of the Bush administration, saying that they have concluded "with a high level of confidence" that the earth is the warmest it has been in the past 400 years.

"There is sufficient evidence from tree rings, boreholes, retreating glaciers, and other "proxies" of past surface temperatures to say with a high level of 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 report from the National Research Council. Less confidence can be placed in proxy-based reconstructions of surface temperatures for A.D. 900 to 1600, said the committee that wrote the report, although the available proxy evidence does indicate that many locations were warmer during the past 25 years than during any other 25-year period since 900."