Persistent suborbital climate variability in marine isotope stage 5

• Main Authors: Lloyd D. Keigwin, Jerry F. Mcmanus, James L. Cullen
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2001
• Subjects: Nordic Sea; North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.462.2532; http://www.climate.unibe.ch/~born/share/papers/eemian_and_lgi/oppo_keigwin01.pao.pdf

Abstract. New surface water records from two high sedimentation rate sites, located in the western subtropical North Atlantic near the axis of the Gulf Stream, provide clear evidence of suborbital climate variations through marine isotope stage (MIS) 5 persisting even into the w-arm peak of the interglaciation (substage 5e). We found that the amplitude of suborbital climate os-cillations did not vary significantly for the whole of MIS 5, implying that ice volume has little or no influence on the ampli-tude of suborbital climate variability in this region. Although some records uggest that longer suborbital 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 link-age occurred for oscillations horter than 4 kyr. However, when examined in conjunction with published ata from the Nor-wegian Sea, new evidence from the subpolar North Atlantic suggests that coupled surface-deepwater oscillations occurred during the penultimate deglaciation. This supports the hypothesis that during glacial and deglacial times, ocean-ice interac-tions and deepwater variability amplify suborbital climate change at higher latitudes. We suggest that during the penultimate deglaciation the North Atlantic deepwater source varied between Nordic Sea and open North Atlantic locations, in parallel with surface temperature oscillations. 1.