Abstract:
The occurrence of carbon isotope minima at the beginning of glacial
terminations is a common feature of planktic foraminifera carbon isotopic
records from the Indo-Pacific, Subantarctic and South Atlantic. We use the
d13C record of a thermocline dwelling foraminifera, Neogloboquadrina
dutertrei, and surface temperature estimates from the eastern equatorial
Pacific to demonstrate that onset
... of d13C minimum events and the initiation of
Southern Ocean warming occurred simultaneously. Timing agreement between the
marine record and the d13C minimum in an Antarctic atmospheric record suggests
that the deglacial events were a response to the breakdown of surface water
stratification, renewed Circumpolar Deep Water upwelling, and advection of low
d13C waters to the convergence zone at the Subantarctic front. Based on age
agreement between the absolute d13C minimum in surface records and the shift
from low to high d13C in the deep South Atlantic, we suggest that the d13C
rise that marks the end of the carbon isotope minima was due to the resumption
of North Atlantic Deep Water influence in the Southern Ocean. 
