A reconstruction of Holocene sea ice variability from the Holsteinsborg Dyb off West Greenland@en

We present a reconstruction of Holocene sea-ice variability from sediment core GA306-GC3, from the Holsteinsborg Dyb off West Greenland, which provides an index of palaeoceanographic and palaeoenvironmental conditions within this climatically sensitive region during the last 6700 yr. The reconstructed sea-ice record, combined with previously published proxy data, suggests that relatively warm conditions with reduced seaice extent prior to 5000 cal. yr BP were associated with the Holocene Thermal Maximum. Subsequent cooling and extensive sea-ice cover between ca. 5000 and 4000 cal. yr BP was followed by even colder conditions and persistent sea-ice cover during the Neoglacial cooling phase, particularly after ca. 1500 cal. yr BP.我们基于西格陵兰外霍尔斯坦斯堡海槽（Holsteinsborg Dyb）的沉积物岩芯GA306-GC3，重建了全新世海冰变化序列，该序列可为过去6700年里这片气候敏感区域的古海洋学与古环境状况提供代用指标。本次重建的海冰记录结合已发表的代用资料显示：距今5000校准年（cal. yr BP）之前，海冰范围缩减的相对暖期与全新世大暖期（Holocene Thermal Maximum）相对应。约5000至4000校准年BP期间，区域出现降温与海冰大范围覆盖；随后的新冰期降温阶段气候更为寒冷，海冰持续覆盖，尤其在约1500校准年BP之后这一特征更为显著。