Tree growth rings and ice cores illuminate the climatic conditions of times gone by. When combined with historical records and documents, climate data can also shed light on important events in human history — including the activities of nomadic groups such as the ancient Türks and Mongols. “Climate data actually can tell us quite a lot about the history of nomadic empires,” said Nicola Di Cosmo, a professor at the Institute for Advanced Study and an expert on China and Inner Asian peoples and environmental history during a recent lecture…
