High-resolution multiproxy reconstruction of extratropical North Atlantic climate dynamics during the last millennium

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Spatiotemporal high-resolution marine proxy records, specifically from extratropical settings, are es-sential to understand forcing and feedback mechanisms operating within the Earth system. As yet, however, even the best resolved record, a sediment core from offshore North Iceland, provides only a 2-5 yr resolution and is strongly summer biased. Such data are insufficient to determine how fast regime shifts occurred or to provide details on spatiotemporal climate dynamics. Extreme events are smoothed out, and the actual sea surface temperature (SST) variance on interannual or seasonal time-scales is not reflected in these records. Furthermore, different proxy SST reconstructions from the same core significantly deviate from each other. For the first time, this study will generate unin-terrupted, millennial-scale, quantitative, multiproxy records (δ18O, δ13C, Sr/Ca, Δ47) of SST, salinity and primary productivity from various regions in the North Atlantic (Iceland, Gulf of Maine, North Sea) providing interannual – and where appropriate seasonal – resolution. Master chronologies will be constructed from shells with overlapping life-spans of the long-lived bivalve, Arctica islandica. Results will significantly improve our understanding of the temporal dynamics of the oceanic Polar Front and regional / basin-wide hydrographic patterns, teleconnections, ocean-atmosphere couplings, decadal climate variability and rapid perturbations in surface waters. These new records can be used as input variables for numerical models of the coupled ocean-atmosphere climate to reduce the uncertainty in future simulations.