Recently a number of high quality climate records from Greenland ice cores and north Atlantic deep-sea sediments have revealed that Holocene climate may not be as stable as previously thought, and that the millennial-scale climate oscillations that characterized the last glacial interval have continued (at a lower amplitude) into the Holocene Epoch. Here I present evidence of such climate variability from a 3.2 meter Holocene section from ODP Site 980, Feni Drift, northeast Atlantic Ocean. I have used 120 closely spaced sediment samples to generate 3 detailed records of variations in surface water conditions: changes in the concentration of >150 micron size lithic grains per gram sediment(IRD), changes in the total planktonic foraminiferal assemblage in the >150 micron size fraction, and changes in oxygen isotopic composition of the surface-dwelling planktonic foraminifer species, N. pahyderma, right-coiling. In addition, I used the total faunal composition to produce the first quantitative estimates of Holocene changes in sub-polar north Atlantic sea surface temperature(SST) using the Modern Analog Technique.

The IRD record reveals at least eight discrete, abrupt small amplitude increases in the IRD concentration after the Younger Dryas separated by longer intervals of little or no IRD input. Each of these events can be directly correlated with similar well-dated events in a lower sediment rate core, VM29-191, located slightly NW of Site 980 where these events are thought to be associated with a series of surface water coolings(Bond, et. al., 1997). Preliminary analysis of non-dissolution related variations in the relative abundances of the five most abundant planktonic foraminiferal species (N. pachyderma, right coiling, G. bulloides, G. glutinata, G. quinqueloba, G. inflata) and the polar species N. pachyderma, left coiling reveal significant Holocene variability, much of which does not seem related in a simple manner to changes in SST and/or to IRD events. There is a weak link between decreases in the relative abundances in N. pachyderma, right coiling and G. glutinata, and increases in G. quinqueloba and the IRD events.

Analysis of SST records estimated using the mean SST associated with the 5 best (and very similar) modern analogs for each sample reveals a series of 1-2°C increases in SST following each of the IRD events with perhaps a slight cooling just before and/or during the event. Overall, the SST record is significantly more stable during the earlier part of the Holocene. Comparison of the SST record with faunal variations of individual species and with the panktonic isotope record (which shows a number of 0.5-1.0 o/oo O-18 enrichment events) suggest significant decoupling of these records, indicating that more complicated hydrographic reorganization in surface waters could be occurring above Site 980 in the NE Atlantic Ocean throughout the Holocene.