A new deep ice core from Akademii Nauk ice cap, Severnaya Zemlya, Eurasian Arctic: first results
A new deep ice core from Akademii Nauk ice cap, Severnaya Zemlya, Eurasian Arctic: first results
复制标题
来自欧亚北极北地岛 Akademii Nauk 冰盖的新深冰芯：初步结果
作者：
D. Fritzsche;F. Wilhelms;L. Savatyugin;J. Pinglot;H. Meyer;H. Hubberten;H. Miller
摘要本文介绍了1999 - 2001年在欧亚北极Severnaya Zemlya Akademii Nauk冰帽上723.91m冰芯的初步结果，并辅以浅层冰芯的资料。冰川的特点是融水的渗透和再冻结，这改变了原有的同位素和化学信号。因此，在这些冰芯中进行地层观测比在格陵兰岛中部或南极洲进行地层观测更为困难。然而，1963年大气核试验产生的人工放射性最大值在深冰芯中可以清楚地探测到，而12.82 m浅冰芯的δ18O剖面显示出年变化。因此，至少在主核的上部，可以预期一个几乎季节性的古气候记录的时间分辨率。与公元2000年地表相关的11.81-12.51m深度的137Cs活性增加检测到切尔诺贝利层。由此得出的年平均净质量平衡为53±2 g cm-2 a-1。主岩心的介电剖面数据显示出相当大的电导率峰值；其中一个被解释为火山事件。根据所得到的年表，这部分地核大约代表过去100年。
Abstract The paper presents first results from the upper 54m of a 723.91m ice core drilled on Akademii Nauk ice cap, Severnaya Zemlya, Eurasian Arctic, in 1999– 2001, supplemented by data from shallow ice cores. the glacier’s peculiarity is the infiltration and refreezing of meltwater, which changes the original isotopic and chemical signals. Therefore, stratigraphical observations in these ice cores are more difficult than in those from central Greenland or Antarctica. However, the 1963 maximum of artificial radioactivity from atmospheric nuclear tests is clearly detectable in the deep ice core, and the δ18O profile of a 12.82 m shallow core shows annual variations. Consequently, at least for the upper part of the main core, an almost seasonal time resolution of palaeoclimate record could be expected. the Chernobyl layer is detected by increased 137Cs activity at depths of 11.81–12.51m related to the AD 2000 surface. the resulting mean annual net mass balance is 53±2 g cm–2 a–1. Data from dielectric profiling of the main core show considerable peaks in conductivity; one of them is interpreted as a volcano event. According to the resulting chronology, this part of the core represents approximately the last 100 years.