Deglacial Meltwater Pulse 1B and Younger Dryas Sea Levels Revisited with Boreholes at Tahiti

Abstract

Episodic Rise Sea-level rise between the end of the Last Glacial Maximum and the beginning of the Holocene accelerated episodically, with the fastest rate occurring during meltwater pulse 1A (14,000 years ago) and perhaps during another interval called meltwater pulse 1B (11,300 years ago). However, existing records are not precise enough to confidently assess sea-level change during meltwater pulse 1B or the Younger Dryas cold event (12,900 to 11,600 years ago). Bard et al. (p. 1235 , published online 14 January) present data from three cores drilled in coral reefs in Tahiti that allow a better quantification of sea-level changes between 14,000 and 9000 years ago. No significant change in the rate of sea-level rise could be detected for the period previously identified as meltwater pulse 1B; reducing the likelihood that such an episode occurred. Furthermore, sea level rose more rapidly at the start of the Younger Dryas but slowed during the rest of the cold event. These findings have implications for our understanding of the dynamics of deglaciation.