Journal Article
The Preboreal climate reversal and a subsequent solar‐forced climate shift
J. van der Plicht; B. van Geel; S. J. P. Bohncke; J. A. A. Bos; M. Blaauw; A. O. M. Speranza; R. Muscheler; S. Björck
Journal of Quaternary Science · Vol. 19, Issue 3 · pp. 263-269 · 2004
Abstract
Accurate chronologies are essential for linking palaeoclimate archives. Carbon‐14 wiggle‐match dating was used to produce an accurate chronology for part of an early Holocene peat sequence from the Borchert (The Netherlands). Following the Younger Dryas–Preboreal transition, two climatic shifts could be inferred. Around 11 400 cal. yr BP the expansion of birch ( Betula ) forest was interrupted by a dry continental phase with dominantly open grassland vegetation, coeval with the PBO (Preboreal Oscillation), as observed in the GRIP ice core. At 11 250 cal. yr BP a sudden shift to a humid climate occurred. This second change appears to be contemporaneous with: (i) a sharp increase of atmospheric 14 C; (ii) a temporary decline of atmospheric CO 2 ; and (iii) an increase in the GRIP 10 Be flux. The close correspondence with excursions of cosmogenic nuclides points to a decline in solar activity, which may have forced the changes in climate and vegetation at around 11 250 cal. yr BP. Copyright © 2004 John Wiley & Sons, Ltd.