Warm periods in the 20th century are not unprecedented during the last 2,000 years

Public Release: 8-Aug-2017

From Eurekalert

Institute of Atmospheric Physics, Chinese Academy of Sciences

IMAGE: 2,000-year temperature reconstruction in China. view more

Credit: Yang Liu & Jingyun Zheng

A great deal of evidence relating to ancient climate variation is preserved in proxy data such as tree rings, lake sediments, ice cores, stalagmites, corals and historical documents, and these sources carry great significance in evaluating the 20th century warming in the context of the last two millennia.

Prof. Quansheng Ge and his group from the Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, collected a large number of proxies and reconstructed a 2000-year temperature series in China with a 10-year resolution, enabling them to quantitatively reveal the characteristics of temperature change in China over a common era.

“We found four warm epochs,” says Prof. Ge, “which were AD 1 to AD 200, AD 550 to AD 760, AD…