The arctic sea ice is a big challenge to the Skeptologist's Medieval Warming Period dogma. First the claim was that the Arctic ice was not changing. Then it's "So what? The sea ice melted as much and more during the MWP.'. Well then, how come ice is melting in supposedly cooler conditions that has been frozen for 4500 years? "Easy. There was ice on top of it that melted during the MWP."
Eat ya heart out RCs and ya Holy Trinity, cos the Skeptologists are here with the amazing ice/no ice duality. Unfortunately, the power of this miracle is only apparent to very devout Skeptologists. For heretics like me, the miracle is a load of schlop, like the evidence for the MWP being hotter than today.