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Holocene Climate Dynamics,
Biogeochemical Cycles
and Ecosystem Variability
in the Eastern Mediterranean Sea
Gerhard Schmiedl, Fanny Adloff, Kay-Christian Emeis,
Rosina Grimm, Michal Kucera, Ernst Maier-Reimer,
Uwe Mikolajewicz, J
ü
rgen M
ö
bius and Katharina M
ü
ller-Navarra
Abstract To understand the processes leading to the formation of Holocene
sapropel S1 in the Eastern Mediterranean Sea, we integrated results from regional
ocean-biogeochemical general circulation model experiments with biogeochemical
and micropaleontological proxy records. Sapropel S1 formed during the Holocene
insolation maximum, when strong Aegean north winds (Etesian) caused enhanced
downwelling and mixing of warm surface waters in the Cretan and western Lev-
antine seas accounting for the complex sea-surface temperature pattern derived
from planktonic foraminiferal transfer functions. Our results support a scenario
where suf
cient organic matter for sapropel formation is buried under oligotrophic
conditions in an anoxic water column refuting the
“
”
hypothesis.
We reconstructed a synchronous shift in the state of deep-sea benthic ecosystems,
documenting a rapid expansion of dysoxic to anoxic conditions with onset of S1
high-productivity
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