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利用主成分分析法对冰岛北部陆架MD99-2275孔中全新世以来沉积物硅藻数据进行研究发现,5000—3000aB.P.,冰岛北部陆架表层古海水温度逐渐上升,来自印明格暖流的北大西洋暖水对该区域的影响有所增强。自3000aB.P.以来,表层海水温度开始稳步下降,北大西洋暖水水团的影响逐步减弱,而来自东格陵兰寒流和东冰岛海流的极地冷水水团的影响显著加强。在晚全新世气候逐渐变冷的过程中,发生了几次短期而显著的气候变冷事件,分别出现在3000—2600aB.P.,1300—1000aB.P.及600—200aB.P.。该中晚全新世古海洋环境记录与格陵兰冰芯(GSIP2)氧同位素气候记录存在良好的对应关系,也与冰岛北部陆架其他海水温度记录有较好的一致性。而冰岛北部陆架区域海底地形的复杂性和海流分布的差异性,以及所采用研究方法的不同则导致该区域各古海水温度记录之间也存在一定的差异性。
Using principal component analysis (PCA) to study the diatoms data of sediments since the Holocene in MD99-2275 boreholes in the northern shelf of Iceland, we find that the paleo-seawater temperature in the surface shelf of northern Iceland increased gradually from 5000-3000 aB.P., The impact of the Atlantic warm water on the region has increased. Since 3000aB.P., The temperature of surface seawater began to decline steadily and the influence of the warm water mass in the North Atlantic Ocean gradually weakened. However, the influence of the polar cold water mass from the cold currents in East Greenland and East Icelandic currents was significantly strengthened. During the late Holocene climate cooling, several short-term and significant climatic cooling events occurred, occurring at 3000-2600aB.P., 1300-1000aB.P. and 600-200aB.P. respectively. The middle-late Holocene paleoenvironmental record has a good correspondence with the Greenland ice core (GSIP2) oxygen isotope climate record, and also has good consistency with other seawater temperature records in northern Iceland. However, the differences of seafloor topography complexity and current distribution in the northern Iceland shelf area and the differences in the research methods used lead to some discrepancies between the records of ancient seawater temperatures in the region.