April 23, 1998: Study Concludes That Last Few Decades Were the Warmest in the Last 1,000 Years

Nature publishes a study by climate scientists Raymond Bradley, Michael Mann, and Malcolm Hughes concluding that the last few decades were warmer than any comparable time period in the last 1,000 years. Their study shows that the pace of warming was most dramatic during the last century. The authors identified the increase of greenhouse gases in the atmosphere as the dominant factor in the observed increase in global temperatures. [Nature, 4/23/1998 ; San Francisco Chronicle, 6/23/2006]