Archaeology and climate: Settlement and lake‐level changes at the Aral Sea

Abstract New archaeological and geomorphologic data collected adjacent to the Aral Sea show lake‐level stands during the late Pleistocene and the past 5000 years. On the northern and southern shores, archaeological sites from the Palaeolithic through the Late Middle Ages contain evidence of various cultures and economies. Changes in settlement activity during the mid‐Holocene are related to several major lake‐level oscillations. Some of them, especially those which occurred at approximately 350–450 cal B.P. (during the Little Ice Age), 700–780 cal B.P., around 1400 cal B.P., and 1600–2000 cal B.P., were accompanied by lithological changes in sediment cores retrieved from the Aral Sea and were observed in shoreline shifts. We show that a maximum lake level at 72–73 m above sea level cannot be corroborated. The highest lake level, which was reached at the beginning of the 20th century, probably never exceeded 54–55 m a.s.l. Furthermore, we documented a previously unknown low‐level stand at 42–43 m a.s.l. that dated to the Bronze Age (∼4000–3000 B.P.). The regression during 1200–1300 cal A.D. was formerly underestimated and was lower than the present‐day lake level. The observed environmental changes, except those since the 1960s, are most probably driven by climate variability, though human activities (e.g., irrigation) can amplify the impact. © 2006 Wiley Periodicals, Inc.

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