Variability of sea-surface temperature and sea-ice cover in the Fram Strait over the last two millennia
Variability of sea-surface temperature and sea-ice cover in the Fram Strait over the last two millennia
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DOI：
10.1016/j.marmicro.2009.12.001
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发表时间：
2010-04-01
影响因子：
1.9
通讯作者：
Husum, Katrine
中科院分区：
文献类型：
--
作者：
Bonnet, Sophie;de Vernal, Anne;Husum, Katrine
分析了位于弗拉姆海峡西斯匹茨卑尔根边缘（北纬78度54.931 '，东经6度46.005'，水深：1497 m）的沉积物芯的藻囊含量，以重建过去2500年的水文气候变化。的相对丰度的dinocyst类群和主成分分析表明，在约300 cal. years BP的重大转变。其特征是嗜热类群Spiniferites mirabilis-hyperacanthus和Impagidinium sphaericum消失，极-亚极类群Impagidinium pallidum和Pentapharsodinium dalei增加。海表温度（SST）估计表明比现在更温暖的条件（异常类似于+2摄氏度），在夏季平均为7摄氏度，直到300 cal.年BP，尽管冷却脉冲记录在1700年左右。1500、1200和800 cal. years BR在过去的300年里，气温从7.6 ℃降至3.5 ℃，海冰覆盖面积每年增加7个月。结果表明，弗拉姆海峡地区是敏感的水文气候变化，特别是相对于海冰和SST，这是连接到相对强度的北向流动的北大西洋沃茨的东部和南流出的冷和新鲜的沃茨从北冰洋。根据我们的数据，我们记录的最温暖的部分大约是1320 cal.年BP，这是过去2500年来唯一的间隔，为现代后AD 2000间隔提供了一个可能的模拟，其特点是海冰自由条件。(C)2009 Elsevier B. V.保留所有权利。
A sediment core located on the West Spitzbergen margin in the Fram Strait (78 degrees 54.931'N, 6 degrees 46.005'E, water depth: 1497 m) was analyzed for its dinocyst content in order to reconstruct hydroclimatic variations of the last 2500 years. The relative abundance of dinocyst taxa and principal component analysis show a major transition at about 300 cal. years BP. It is characterized by the disappearance of thermophilic taxa Spiniferites mirabilis-hyperacanthus and Impagidinium sphaericum and the increase of polar-subpolar taxa Impagidinium pallidum and Pentapharsodinium dalei. Sea-surface temperature (SST) estimates suggest warmer conditions than present (anomaly similar to+2 degrees C) averaging at 7 degrees C in summer until 300 cal. years BP, although cooling pulses are recorded around 1700. 1500, 1200 and 800 cal. years BR The last 300 years were marked by a cooling from 7.6 to 3.5 degrees C and sea-ice cover increasing up to 7 months/yr. The results demonstrate that the Fram Strait area is sensitive to hydroclimatic variations, notably with respect to sea-ice and SSTs, which are linked to the relative strength of northward flow of North Atlantic waters to the East and southward outflow of cold and fresh waters from the Arctic Ocean. Based on our data, the warmest part of our record around 1320 cal. years BP is the only interval of the last 2500 years that provides a possible analogue for the modern post-AD 2000 interval, which is characterized by sea-ice free conditions. (C) 2009 Elsevier B.V. All rights reserved.