If you think the Earth is hot now, try wearing plate armor in the Middle Ages.
A Swedish study found that the planet was warmer in [the Roman era] and the Middle Ages than today, challenging the mainstream idea that man-made greenhouse gas emissions are the main drivers of global warming.
The study, by scientist Leif Kullman, analyzed 455 “radiocarbon-dated mega-fossils” in the Scandes mountains and found that tree lines for different species of trees were higher during the Roman and Medieval times than they are today. Not only that, but the temperatures were higher as well.
All other things being equal, adding more greenhouse gases to the atmosphere will have a warming effect on the planet,” Judith Curry, a climatologist at the Georgia Institute of Technology, told the Los Angeles Times. “However, all things are never equal, and what we are seeing is natural climate variability dominating over human impact.
At least as far back as 2005 (and actually, far earlier) scientists were discovering entire prehistoric villages in the Swiss Alps as glaciers retreated: The Alps had far less ice from 5,000 – 850 BC., then froze up again until Roman Times and stayed open through the medieval period.
None of this is news to the scientific community; all of it is ignored and suppressed, however. The science is settled, alright: the earth’s temperature fluctuates over time, independent of human activity.