Holocene sea subsurface and surface water masses in the Fram Strait – Comparisons of temperature and sea-ice reconstructions
Holocene sea subsurface and surface water masses in the Fram Strait – Comparisons of temperature and sea-ice reconstructions
复制标题
弗拉姆海峡全新世海洋地下和表层水团——温度和海冰重建的比较
DOI：
10.1016/j.quascirev.2015.09.007
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发表时间：
2016
影响因子：
4
通讯作者：
L. Polyak
中科院分区：
文献类型：
--
作者：
K. Werner;J. Müller;K. Husum;R. Spielhagen;E. Kandiano;L. Polyak
研究人员对来自弗拉姆海峡东部的两个高分辨率沉积岩芯进行了全新世（过去约 12,000 年）期间海洋地下和表面温度变化的研究。 Husum 和 Hald（2012）开发的传递函数已应用于沉积物岩心，以重建整个时期海洋地下温度的波动。其他生物标志物和有孔虫代理数据用于阐明地表和地下水团条件之间的变化，并得出西斯匹次卑尔根大陆边缘全新世气候和海洋变化的结论。结果一致显示，在大约 5 cal ka BP 之前，温暖的海面到地下温度高达 6 °C，最高海水温度约为 10 cal ka BP，可能与当时发生的 7 月最大日照有关。根据有孔虫和甲虫温度重建，最大大西洋水 (AW) 平流发生在 10.6 至 8.5 cal ka BP 之间的地表和地下。大约在 10 到 9 cal ka BP 之间，弗拉姆海峡东部盛行着层理较少、无冰、营养丰富的表层海洋，并伴有强烈的 AW 平流。在大约 5 cal ka BP 之后，当地下温度急剧下降且最小值在大约 4 到 3 cal ka BP 之间时，发现 AW 贡献减弱。此外，全新世晚期的寒冷条件还受到浮游有孔虫壳的高度破碎和亚极地浮游有孔虫物种 Turborotalita quinqueloba 的高 δ18O 值的支持。虽然与 IP25 相关的指数以及恐龙囊数据表明，由于初夏日照减少导致持续变冷，并因此自地表水域约 7 cal ka BP 以来海冰增加，但包括稳定同位素在内的浮游有孔虫数据表明，自约 3 cal ka BP 以来，较强的地下 AW 流入略有恢复。在全新世后期观察到的地表水和地下水的脱钩很可能归因于强大的密斜层将寒冷的海冰供给的地表水与增强的地下AW平流分开。这可能与北大西洋副极地与副热带环流活动的变化有关。
Two high-resolution sediment cores from eastern Fram Strait have been investigated for sea subsurface and surface temperature variability during the Holocene (the past ca 12,000 years). The transfer function developed by Husum and Hald (2012) has been applied to sediment cores in order to reconstruct fluctuations of sea subsurface temperatures throughout the period. Additional biomarker and foraminiferal proxy data are used to elucidate variability between surface and subsurface water mass conditions, and to conclude on the Holocene climate and oceanographic variability on the West Spitsbergen continental margin. Results consistently reveal warm sea surface to subsurface temperatures of up to 6 °C until ca 5 cal ka BP, with maximum seawater temperatures around 10 cal ka BP, likely related to maximum July insolation occurring at that time. Maximum Atlantic Water (AW) advection occurred at surface and subsurface between 10.6 and 8.5 cal ka BP based on both foraminiferal and dinocyst temperature reconstructions. Probably, a less-stratified, ice-free, nutrient-rich surface ocean with strong AW advection prevailed in the eastern Fram Strait between 10 and 9 cal ka BP. Weakened AW contribution is found after ca 5 cal ka BP when subsurface temperatures strongly decrease with minimum values between ca 4 and 3 cal ka BP. Cold late Holocene conditions are furthermore supported by high planktic foraminifer shell fragmentation and high δ18O values of the subpolar planktic foraminifer speciesTurborotalita quinqueloba. While IP25-associated indices as well as dinocyst data suggest a sustained cooling due to a decrease in early summer insolation and consequently sea-ice increase since about 7 cal ka BP in surface waters, planktic foraminiferal data including stable isotopes indicate a slight return of stronger subsurface AW influx since ca 3 cal ka BP. The observed decoupling of surface and subsurface waters during the later Holocene is most likely attributed to a strong pycnocline layer separating cold sea-ice fed surface waters from enhanced subsurface AW advection. This may be related to changes in North Atlantic subpolar versus subtropical gyre activity.
DOI：
10.1016/j.palaeo.2011.05.030
发表时间：
2011-08
期刊：
Palaeogeography, Palaeoclimatology, Palaeoecology
影响因子：
--
作者：
K. Werner;R. Spielhagen;D. Bauch;H. Hass;E. Kandiano;Katarzyna Zamelczyk
通讯作者：
K. Werner;R. Spielhagen;D. Bauch;H. Hass;E. Kandiano;Katarzyna Zamelczyk
影响因子：
3
作者：
Belt, Simon T.;Masse, Guillaume;LeBlanc, Bernard
通讯作者：
LeBlanc, Bernard