To some extent, 1000-year temperature histories are moderately irrelevent to modern global warming discussions. In fact, it is fairly amazing that the evidence of tree rings and such over 1000 years is discussed more than the instrumental record of the last 100, which tends to undercut most catastrophic warming forecasts. However, catastrophists have attempted to use these past temperature reconstructions to make the argument that temperatures were incredibly stable and low right up to the point that man has made them higher and less stable in the last 100 years. For this reason it is worth discussing them, if only to refute this conclusion.
