Abrupt increase in Greenland snow accumulation at the end of the Younger Dryas event ...

• Main Authors: Alley, R. B., Meeset, D. A., Shuman, Christopher, Gowt, A. J., Taylor, K. C., Grootes, P. M., White, J. W. C., Ram, M., Waddington, E. D., Mayewski, P. A., Zielinski, G. A.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Nature 1993
• Subjects: Greenland; Greenland ice core; Greenland ice cores; ice core
• Online Access: https://dx.doi.org/10.13016/m26vgy-bto8; https://mdsoar.org/handle/11603/24307

THE warming at the end of the last glaciation was characterized by a series of abrupt returns to glacial climate, the best-known of which is the Younger Dryas event1. Despite much study of the causes of this event and the mechanisms by which it ended, many questions remain unresolved1. Oxygen isotope data from Greenland ice cores²⁻⁴ suggest that the Younger Dryas ended abruptly, over a period of about 50 years; dust concentrations²,⁴ in these cores show an even more rapid transition (≲20 years). This extremely short timescale places severe constraints on the mechanisms underlying the transition. But dust concentrations can reflect subtle changes in atmospheric circulation, which need not be associated with a large change in climate. Here we present results from a new Greenland ice core (GISP2) showing that snow accumulation doubled rapidly from the Younger Dryas event to the subsequent Preboreal interval, possibly in one to three years. We also find that the accumulation-rate change from the Oldest Dryas to ...