A 500 yr speleothem-derived reconstruction of late autumn-winter precipitation, northeast Turkey

A verified instrumental calibration of annually resolved delta O-18 for a stalagmite from Gumushane in northeast Turkey is presented and cross-validated using a 'leave-one-out' technique. The amount of late autumn to winter precipitation is negatively correlated with stalagmite delta O-18 between AD 1938 and 2004. The observed relationship is extrapolated back to similar to AD 1500 leading to the first long winter precipitation reconstruction for this region. Modern day October to January precipitation is linked to pressure fields in Western Russia. Anomalously lower reconstructed rainfall is recorded in AD 1540-1560 at which time higher pressure over the Caspian Sea region is inferred. (C) 2011 University of Washington. Published by Elsevier Inc. All rights reserved.