Tag Archives: Anthropogenic global warming

On tree rings, CO2 levels and the Pliocene

A study of tree-ring data recently found that in some regions temperatures during Roman times (21AD to 50AD) were 1.05 degrees Celsius higher than the 1951-1980 mean. The paper’s lead author, Professor Jan Esper of Johannes Gutenberg University in Mainz, Germany, and his colleagues wrote that: “large-scale near-surface air-temperature reconstructions relying on tree-ring data may […] … learn more→