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18
O records (Fleitmann et al.
2009
; Badertscher et al.
North Anatolian speleothem
δ
18
O values from the Black Sea itself unison document the early
Fennoscandian Ice Sheet disintegration initially routing its melt water to the Caspian
and Black Seas (Fig.
2
c; Wegwerth et al.
2014
). The postglacial warming of the Black
Sea lake starting at
2011
) and ostracod
δ
14.7 ka BP for Termination II (T II) and Termi-
nation I (T I), respectively, is accompanied by authigenic calcite precipitation
(Fig.
2
d) induced by augmented phytoplankton blooms during the warm season
indicated e.g., by dinocyst concentrations (Fig.
2
e). While T II shows steadily
increasing carbonate precipitation, a prominent interruption during the Younger
Dryas characterizes T I. With the connection to the Mediterranean Sea related to the
postglacial sea-level rise (Eemian at
130.5 and
*
*
8.3 ka BP),
calcite precipitation ceases and organic-rich sedimentation under anoxic conditions
128 ka BP and Holocene at
*
*
—
the sapropel formation
starts. Eemian dinocyst assemblages differ considerably
from the Holocene showing the presence of fully marine species. An increased in
—
fl
ow
of Mediterranean water triggered by a
6 m higher-than-today global sea level
and higher temperatures at the beginning of the Eemian are likely explaining higher-
than-present sea-surface salinity of about 28
*
-
30 psu (Fig.
2
e; Shumilovskikh et al.
2013a
).
Terrestrial proxies, presented by pollen and speleothem
13
C values, indicate open
steppe and steppe-forest landscapes typical for cold/arid conditions at the end of both
glacial periods and spread of forests and increased soil productivity under warm/
humid conditions during both interglacials (Fig.
2
a,b). Initial warming started at
130.4 ka BP during TII and at 14.7 ka BP during TI, and is clearly re
δ
ected by
increase of arboreal and especially oak and pine pollen (Shumilovskikh et al.
2012
,
2013b
) and more negative speleothem
fl
13
C values (Fleitmann et al.
2009
). The onset
of interglacials is indicated by arboreal pollen exceeding 50 % (Eemian at
δ
128.8 ka
*
BP and Holocene at
10.6 ka BP) and is characterized by semi-arid conditions as
revealed by the dominance of pines and oaks. Spread of typical euxinian beech
forests during both interglacial periods coincides with the Mediterranean in
*
ow into
the Black Sea basin, suggesting establishment of temperate climatic conditions after
128 and 8.3 ka BP (Fig.
2
b). High abundance of pine indicates generally cooler and
dryer conditions during the Holocene (Shumilovskikh et al.
2012
), whereas warm-
temperate forests dominate the Eemian and were possibly caused by a more pro-
nounced northern summer insolation maximum (Fig.
2
g; Shumilovskikh et al.
2013b
). The early Holocene humidity increase as indicated by the arboreal pollen
record (Fig.
2
b) is slightly later when compared to records from the eastern Medi-
terranean region. These delays are known from different parts of Anatolia and were
potentially attributed to changes in precipitation seasonality. Less densely vegetated
landscapes at the end of the Holocene suggest dryer climate and/or increased
anthropogenic activity (Shumilovskikh et al.
2012
).
The terrestrial and aquatic environments at the southern rim of the Black Sea
demonstrably experienced large changes in the course of the last two terminations
and the succeeding interglacials. Shifting precipitation/evaporation regimes largely
relate to a postglacial northward retreat of the polar frontal systems and regional
warming. However, the hydrological regime of the Black Sea was punctuated by
fl
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