Vegetation history of the penultimate glacial period (Marine Isotope Stage 6) at Ioannina, north-west Greece

The vegetational history of the penultimate glacial period, Marine Isotope Stage (MIS) 6 (c. 185-135 ka), has remained relatively unexplored. Here we present a new record from the Ioannina basin, north-west Greece, which constitutes the highest-resolution terrestrial pollen record for this interval produced to date. It shows that the vegetation history of MIS 6 in this region can be divided into two parts: an early period (185-155 ka) with pronounced oscillations in tree population extent, and a later period (155 135 ka) with much smaller tree populations and subdued oscillations. This pattern is analogous to the MIS 3/MIS 2 division during the last glacial in the same sequence, although the early part of MIS 6 had larger Pinus populations and fewer temperate trees relative to the equivalent interval in MIS 3. This implies cooler and wetter conditions, which is somewhat counterintuitive given the high summer insolation during MIS 6e, but is in line with other palaeoclimatic evidence from the Mediterranean. Comparison with North Atlantic records suggests that despite the absence of pronounced iceberg discharges during MIS 6, North Atlantic millennial-scale variability had a significant downstream impact on tree populations in north-west Greece. Copyright (C) 2011 John Wiley & Sons, Ltd.