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Differentiating natural climate change from anthropogenic forcing is a major challenge in the prediction of future climates. In this context, the investigation of interglacials provides valuable information on natural climate variability during periods that resemble the present. This paper shows that natural cyclic changes in winter climates affected central European environments during the last interglacial, i.e., the Eemian, 126-110 ka. As a result of the extraordinarily high counting sums performed at Eemian pollen samples, it was possible to reveal a robust presence-absence pattern of the insect-pollinated, and therefore in the pollen rain underrepresented, taxon Hedera. This plant is known to require the influence of oceanic winter climates, i.e., moist and mild, in northwest and central Europe. By analogy with recent findings from the North Atlantic's Holocene interglacial, the trigger of the Eemian climate variability may have been changes in solar activity, possibly amplified by changes in North Atlantic ocean currents and/or in the North Atlantic Oscillation. Our findings suggest natural cyclic changes to be a persistent feature of interglacial climates. Keywords: climate change, solar activity, environmental change, Eemian, Europe.

New evidence from basin modeling documents a nearly synchronous episode of rapid subsidence between MIddle Devonian and earliest Mississippian time in almost all preexisting margins and interior basins of North America. The subsidence events appear to have been accompanied by a large sea-level rise relative t the stable cratonic platform. Herein we suggest that the timing and magnitude of basin subsidence and sea-level change are compatible with predictions by recent mantle-convection models for the assembly of supercontinents. If so, the sea-level and subsidence events were consequences of the onset of accretion of Pangea above a major zone of mantle downwelling.

Three separate oceanic studies have established that the operations of the Atlantic Ocean's conveyor belt underwent rapid and recurring changes during the last glaciation. Results also suggest a correlation between changes in the operations of the Atlantic conveyor and climatic changes. The instability and erratic behavior of the Atlantic's conveyor as suggested by the results is consistent with the results achieved by simulations. Possible causes for the discrepancies in the results of the three studies are discussed.