"it is a central plank of climate policy worldwide that the current temperatures are the highest ever seen for many millennia, and that this results from rising

"it is a central plank of climate policy worldwide that the current temperatures are the highest ever seen for many millennia, and that this results from rising levels of atmospheric CO2 emitted by human activities" No, it's not. It's known (see edit) that the earth was warmer about 1,000 years ago - it was part of why I resisted climate science for so long (the Roman part is new to me, though of course no Romans were growing trees in Scandinavia). That it was hotter then does not mean recent warming is natural - it just means needing other evidence for claims of human contribution. Which I believe exists. Edit: http://en.wikipedia.org/wiki/Medieval_Warm_Period http://en.wikipedia.org/wiki/Medieval_Warm_Period