Read here. More scientific evidence that modern temperatures are not "unprecedented" as claimed by the IPCC and the Climategate scientists. (click image to enlarge)
"....developed a time series of C4 vs. C3 plant dynamics for the past 12,000 14C years in the mixed and shortgrass prairie of the U.S. Great Plains; and because the percent soil carbon derived from C4 plants "corresponds strongly with summer temperatures as reflected in the soil carbon pool," as they [Nordt et al.] describe it, they were able to derive a history of the relative warmth of the region that indicates that the peak warmth of the Medieval Warm Period was slightly greater than it has yet to be during the Current Warm Period." [Nordt, L., von Fischer, J., Tieszen, L. and Tubbs, J. 2008.]
More historical charts here. Other climate history postings here. Modern temperature charts.