Actually, the European researchers confirmed that the "unprecedented" modern global warming is not only less than the Medieval Period, it is less than most of the prior warming phases over the last 10,000 years - using multiple proxies, this study shreds the 'Hockey Stick' hypothesis of Penn State's 'winner of the Nobel Prize pretender'
(click image to enlarge)
Read here. Michael Mann's widely discredited 'Hockey Stick' hypothesis takes huge hit from objective, reputable scientists.
As the chart depicts, over the last 10,000 years multiple periods had warmer temperatures than our current modern temperatures. Clearly, today's temperatures are not "unprecedented."
"In the words of the authors, "we reconstructed temperature series of both Northern and Southern Norway based on numerous studies in Scandinavia examining pollen and plant macrofossils in lake sediment cores, chironomids in sediment cores, tree line changes, and deposition rate of speleothems."...it can be seen that after the planet finally emerged from the last great period of glaciation, the coldest interval of the current interglacial occurred during the depths of the Little Ice Age, which prevailed just prior to the warming that ushered the planet into its current period of warmth, which is still far less than that of much of the prior part of the record. And as a result of this fact, there would appear to be nothing unusual about the earth warming a good deal more than it already has sometime in the near future, without any need to invoke anthropogenic CO2 emissions as an explanation for the warming." [Karianne S. Lilleøren, Bernd Etzelmüller, Thomas V. Schuler, Kjersti Gisnås, Ole Humlum 2012: Global and Planetary Change]
Additional climate-history and peer-reviewed postings. Historical temperature charts.