An examination of two documented periods of climate change in the greater Middle East, between approximately 4,500 and 3,000 years ago, reveals local evidence of resilience and even of a flourishing ancient society despite the changes in climate seen in the larger region.
A new study – led by archaeologists from Cornell and from the University of Toronto, working at Tell Tayinat in southeastern Turkey – demonstrates that human responses to climate change are variable and must be examined using extensive and precise data gathered at the local level.
“The absolute dating of these periods has been a subject of considerable debate for many years, and this study contributes a significant new dataset that helps address many of the questions,” said Sturt Manning, the Goldwin Smith Professor of Classical Archaeology in the College of Arts and Sciences, and lead author of the study, which published Oct. 29 in PLoS ONE.
The report highlights how challenge and collapse in some areas were matched by resilience and opportunities elsewhere. The findings are welcome contributions to discussions about human responses to climate change that broaden an otherwise sparse chronological framework for the northern part of the region known historically as the Levant, which stretches the length of the eastern edge of the Mediterranean Sea.
“The study shows the end of the Early Bronze Age occupation at Tayinat was a long and drawn out affair that, while it appears to coincide with the onset of a megadrought 4,200 years ago, was actually the culmination of processes that began much earlier,” said Tim Harrison, professor and chair of the Department of Near & Middle Eastern Civilizations at the University of Toronto. Harrison directs the Tayinat Archaeological Project.
“The archaeological evidence does not point towards significant local effects of the climate episode,” he said, “as there is no evidence of drought stress in crops. Instead, these changes were more likely the result of local political and spatial reconfiguration.”
The mid- to late Early Bronze Age (3000-2000 B.C.) and the Late Bronze Age (1600-1200 B.C.) in the ancient Middle East are pivotal periods of early inter-connectedness among settlements across the region, with the development of some of the earliest cities and state-level societies. But these systems were not always sustainable, and both periods ended in collapse of civilizations and settlements, the reasons for which are highly debated.
The absence of detailed timelines for societal activity throughout the region leaves a significant gap in understanding the associations between climate change and social responses. While the disintegration of political or economic systems are indeed components of a societal response, collapse is rarely total.
Using radiocarbon dating and analysis of archaeological samples recovered from Tell Tayinat, a location occupied following two particularly notable climate change episodes – one occurring 4,200 years ago, the other 1,000 years later – Manning and Brita Lorentzen, a researcher at the Cornell Tree-Ring Laboratory, working with the University of Toronto team, established a firm chronological timeframe for Tayinat in these two pivotal periods in the history of the ancient Middle East.
“The detailed chronological resolution achieved in this study,” Manning said, “allows for a more substantive interpretation of the archaeological evidence in terms of local and regional responses to proposed climate change, shedding light on how humans respond to environmental stress and variability.”
The researchers say the chronological framework for the Early Iron Age demonstrates the thriving resettlement of Tayinat following the latter climate change event, during a reconstructed period of heightened aridity.
“The settlement of Tayinat may have been undertaken to maximize access to arable land, and crop evidence reveals the continued cultivation of numerous water-demanding crops, revealing a response that counters the picture of a drought-stricken region,” Harrison said. “The Iron Age at Tayinat represents a significant degree of societal resilience during a period of climatic stress.”
The research was supported by the Social Sciences and Humanities Research Council of Canada, and by the University of Toronto.