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Climate alarmists have claimed for quite some time that late-20th-century and early-21st-century global temperatures were so high as to merit the word "unprecedented" when comparing them to temperatures of the past millennium or two; and they also claim that this achievement was both driven and sustained by the carbon dioxide or CO2 released to the air by mankind's burning of fossil fuels such as coal, gas and oil. But to maintain this dual contention, they have been forced to further contend that the well-known Medieval Warm Period was neither hemispheric nor global in scope, but merely confined to the much smaller region surrounding the North Atlantic Ocean. And they have also had to contend that the MWP was never really as warm as it had long been believed to be.
The results of the several studies described greatly advance the thesis that the MWP was indeed a global phenomenon, wherein temperatures throughout the world were significantly warmer than they have been anytime subsequently, and that there is thus nothing unusual or unprecedented about earth's current level of warmth.