Antarctic ice-core data reveal that the atmosphere experienced abrupt centennial increases in CO<inf>2</inf> concentration during the last deglaciation (∼18 thousand to 11 thousand years ago). Establishing the role of ocean circulation in these changes requires highresolution, accurately dated marine records. Here, we report radiocarbon data from uranium-thorium-dated deep-sea corals in the Equatorial Atlantic and Drake Passage over the past 25,000 years. Two major deglacial radiocarbon shifts occurred in phase with centennial atmospheric CO<inf>2</inf> rises at 14.8 thousand and 11.7 thousand years ago. We interpret these radiocarbon-enriched signals to represent two short-lived (less than 500 years) "overshoot" events, with Atlantic meridional overturning stronger than that of the modern era. These results provide compelling evidence for a close coupling of ocean circulation and centennial climate events during the last deglaciation.