So why was it so warm 800 years ago?
The Washington Post reports:
The latest review of climate science from the Intergovernmental Panel on Climate Change (IPCC), though not finalized, is making the rounds. The prevailing headline is that the panel is more certain than ever that most of the warming observed in recent decades is human-caused. It’s level of certainty has increased from at least 90 percent in 2007 to at least 95 percent in the new report.
Officials from the IPCC stress that the leaked draft is not its final product. A government review is ongoing, so some of the conclusions may be altered. But here are some of the more interesting preliminary findings…