Natural mechanism for medieval warming discovered

Europe basked in unusually warm weather in medieval times, but why has been open to debate. Now the natural climate mechanism that caused the mild spell seems to have been pinpointed.

The finding is significant today because, according to Valerie Trouet at the Swiss Federal Institute for Forest, Snow, and Landscape Research in Birmensdorf, the mechanism that caused the warm spell

The finding scuppers one of the favourite arguments of climate-change deniers. If Europe had temperature increases before we started emitting large amounts of greenhouse gases, the theory goes, then maybe the current global warming isn’t caused by humans, either.

New Scientist