Work package POL 6: Earth climate variability since the Miocene
Natural climate variability is documented in continental ice, permafrost and marine sediment
cores that represent unique archives of the timing and amplitude of climatic change at
seasonal to millennial time scales covering long periods and a broad variety of conditions
distinct from recent times. The decoding of the mechanisms driving and amplifying Earth’s
climate variability represents an essential prerequisite for the generation of numerical
models allowing realistic simulations of past and future climate development. Special
emphasis of our integrated ice/sediment/permafrost studies is placed on
• the determination of physical and biological processes that regulate atmospheric
CO2 concentrations during Pleistocene climate variability via ocean/atmosphere
exchange;
• the identification of cryosphere- (ice sheet instability, melt water input, sea ice)
related effects on ecosystems, thermohaline ocean circulation and sea level;
• the causes of warmer (higher sea level) than present conditions;
• the variability range and driving mechanisms of climate change at sub-millennial
time scales during warm and cold climates;
• the detection of processes generating the range of variability between different
climate cycles, as well as the shift in climate cycles periodicity, and
• the recognition of climate interhemispheric connections (e.g. bipolar see-saw) and
involved transfer/feedback mechanisms.