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

时空高分辨率海洋记录，特别是来自温带环境的记录，对于理解地球系统内的强迫和反馈机制是有意义的。然而，到目前为止，即使是分辨率最好的记录，来自冰岛北部近海的沉积岩芯，也只提供了2-5年的分辨率，并且强烈地偏向夏季。这些数据不足以确定体制转变发生的速度有多快，也不足以提供时空气候动态的细节。极端事件被平滑，在年际或季节时间尺度上的实际海表面温度(SST)变化没有反映在这些记录中。此外，来自同一核心的不同代理SST重建彼此之间存在明显的偏差。这项研究将首次产生北大西洋(冰岛、缅因湾、北海)不同区域(冰岛、缅因湾、北海)的海温、盐度和初级生产力的不间断、千年尺度的定量多指标记录(δ18O，δ13C，SR/Ca，Δ47)，提供年际分辨率，并在适当的情况下提供季节性分辨率。主年表将由寿命较长的双壳类动物北极岛的贝壳组成。这些结果将大大增进我们对海洋极锋和区域/盆地范围水文模式、遥相关、海洋-大气耦合、十年气候变异性和地表水快速扰动的时间动态的理解。这些新记录可以作为海-气耦合气候数值模式的输入变量，以减少未来模拟中的不确定性。

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.