Sub-Milankovitch cyclicity in spore and pollen records from Eocene Lake Messel

The annually laminated oil shale from the Eocene maar lake at Messel (Germany) provides unique palaeoenvironmental and palaeoclimatological information for the Palaeogene greenhouse phase. Two palynological analyses of 6.3 and 70?kyr long records with a temporal resolution of 70 and 700?years respectively confirm vegetation and climate variability in the sub-Milankovitch range. This variability clearly corresponds to cyclic climate fluctuations indicating the influence of solar activity and a millennial-scale variability of the El Niño?Southern Oscillation also seen during the Quaternary icehouse system. This provides strong evidence of cyclic fluctuations in the sub-Milankovitch frequency band that represent a pervasive and persistent system not only of the Quaternary icehouse, but also throughout the entire Neogene and the Palaeogene greenhouse. This is proof for the long-term stability of the driving forces of natural climate change on Earth. Fluctuations in the frequency of palynomorphs indicate cyclic short-term quantitative changes in the composition of the vegetation. These changes were related to precipitation and corresponding fluctuations of the lake level as well as to changes in pollen production, transport and deposition.