Thirumalai Kaustubh, Quinn Terrence M, Okumura Yuko, Richey Julie N, Partin Judson W, Poore Richard Z, Moreno-Chamarro Eduardo
Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, J.J. Pickle Research Campus, Building 196, 10100 Burnet Road (R2200), Austin, TX, 78758, USA.
Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, 1 University Station C9000, Austin, TX, 78712, USA.
Nat Commun. 2018 Jan 26;9(1):392. doi: 10.1038/s41467-018-02846-4.
Surface-ocean circulation in the northern Atlantic Ocean influences Northern Hemisphere climate. Century-scale circulation variability in the Atlantic Ocean, however, is poorly constrained due to insufficiently-resolved paleoceanographic records. Here we present a replicated reconstruction of sea-surface temperature and salinity from a site sensitive to North Atlantic circulation in the Gulf of Mexico which reveals pronounced centennial-scale variability over the late Holocene. We find significant correlations on these timescales between salinity changes in the Atlantic, a diagnostic parameter of circulation, and widespread precipitation anomalies using three approaches: multiproxy synthesis, observational datasets, and a transient simulation. Our results demonstrate links between centennial changes in northern Atlantic surface-circulation and hydroclimate changes in the adjacent continents over the late Holocene. Notably, our findings reveal that weakened surface-circulation in the Atlantic Ocean was concomitant with well-documented rainfall anomalies in the Western Hemisphere during the Little Ice Age.
北大西洋的表层海洋环流影响着北半球气候。然而，由于古海洋学记录分辨率不足，大西洋百年尺度的环流变率受到的限制很大。在此，我们展示了一个对墨西哥湾北大西洋环流敏感站点的海面温度和盐度的重复重建，该重建揭示了全新世晚期明显的百年尺度变率。我们使用三种方法，即多指标综合分析、观测数据集和瞬态模拟，发现在这些时间尺度上，作为环流诊断参数的大西洋盐度变化与广泛的降水异常之间存在显著相关性。我们的结果表明，全新世晚期北大西洋表层环流的百年变化与相邻大陆的水文气候变化之间存在联系。值得注意的是，我们的研究结果表明，在小冰期期间，大西洋表层环流减弱与西半球有充分记录的降雨异常同时出现。
