Immediate temperature response in northern Iberia to last deglacial changes in the North Atlantic

Abstract

Major disruptions in the North Atlantic circulation during the last deglaciation triggered a series of climate feedbacks that influenced the course of Termination I, suggesting an almost synchronous response in the ocean-atmosphere system. We present a replicated δ18O stalagmite record from Ostolo cave in the northern Iberian Peninsula with a robust chronological framework that continuously covers the last deglaciation (18.5–10.5 kyr B.P.). The Ostolo δ18O record, unlike other speleothem records in the region that were related to humidity changes, closely tracks the well-known high-latitude temperature evolution, offering important insights into the structure of the last deglaciation in the Northern Hemisphere. In addition, this new record is accompanied by a clear signal of the expected cooling events associated with the deglacial disruptions in North Atlantic deep convection during Heinrich event 1.