Persistent suborbital climate variability in marine isotope stage 5 and Termination II

New surface water records from two high sedimentation rate sites, located i n the western subtropical North Atlantic near the axis of the Gulf Stream, provide clear evidence of suborbital climate variations through marine isot ope stage (MIS) 5 persisting even into the warm peak of the interglaciation (substage 5e). We found that the amplitude of suborbital climate oscillati ons did not vary significantly for the whole of MIS 5, implying that ice vo lume has little or no influence on the amplitude of suborbital climate vari ability in this region. Although some records suggest that longer suborbita l variations (4-10 kyr) during MIS 5 are linked to deepwater changes, none of the existing records is of sufficient resolution to assess if a linkage occurred for oscillations shorter than 4 kyr. However, when examined in con junction with published data from the Norwegian Sea, new evidence from the subpolar North Atlantic suggests that coupled surface-deepwater oscillation s occurred during the penultimate deglaciation. This supports the hypothesi s that during glacial and deglacial times, ocean-ice interactions and deepw ater variability amplify suborbital climate change at higher latitudes. We suggest that during the penultimate deglaciation the North Atlantic deepwat er source varied between Nordic Sea and open North Atlantic locations, in p arallel with surface temperature oscillations.