Abstract
Antarctica has been proposed as the dominant source of the meltwater
that entered the oceans during Meltwater Pulse 1b (MWP1b) that occurred
approximately 11,500 years ago. The deglaciation of heavily glaciated
fjords off the coast of Antarctica at approximately this time has
provided support for this hypothesis. Further support for this scenario
was provided by the fact that the highly non-monotonic relative sea
level histories recorded at sites on the coast of Scotland, which had
been heavily glaciated at last glacial maximum, could be explained by
the inter-hemispheric sea level teleconnection associated with a
significant deglaciation of Antarctic ice sheets at this time. That the
magnitude of grounded ice loss from Antarctica at MWP1b time was
adequate to provide the necessary RSL rise along the coast of Scotland
has not been demonstrated. Furthermore, there exist implicit suggestions
to the effect that a significant contribution to MWP1b must have also
been delivered to the oceans by the abrupt northern hemisphere warming
that occurred at the end of the Younger Dryas (YD) cold reversal, which
also occurred approximately 11,500 years ago. This warming event
occurred due to the rapid intensification of the Atlantic Meridional
Overturning Circulation (AMOC) when it recovered after the YD. We
present a fingerprinting analysis of the contribution of all major ice
sheets to MWP1b using the ICE7G_NA (VM7) model of ice loading history
and find that the best agreement between calculated sea level curves and
observations is obtained with a minimal Antarctic contribution.