Pathways of shelf waters and Pacific-derived waters in the Arctic Ocean halocline inferred from stable oxygen isotopes

该项目的目的是对北冰洋内的水团分布和环流进行定量评估。水的稳定氧同位素（d18O）是一种保守的示踪剂，将与水化学数据一起用于研究陆架来源的淡水（即河水和海冰来源的融水/盐水）和太平洋来源的水的影响。这样，这些水对盐跃层、大西洋层以及北冰洋的深水和底水的影响将被量化。众所周知，北冰洋太平洋分量的分布存在年代际变化，但最近在2007年跨极漂流流的淡水分布中也观察到强烈的变化，从而表明了额外的年际变化。目前尚不清楚2007年观测到的变化是否是一个永久性的特征，以及它们是否与那段时间太平洋水域的消失有关。因此，计划对北冰洋盐跃层中的淡水和太平洋水进行全面定量评价将有助于进一步了解北冰洋水文对北极和全球气候变化的影响和潜在反馈。

The purpose of the project is to provide a quantitative assessment of water mass distribution and circulation within the Arctic Ocean. Stable oxygen isotopes (d18O) of the water aeltare a conservative tracer and will be used together with hydro-chemical data to study the influence of shelf-derived freshwaters (i.e. river water and sea-ice derived melt/brine waters) and Pacific-derived waters. In doing so the impact of these waters on the halocline, the Atlantic layer and the Deep and Bottom waters of the Arctic Ocean will be quantified. It is known that there are inter-decadal variations in the distribution of the Pacific component in the Arctic Ocean but recently also strong variations were observed in freshwater distributions in the Transpolar Drift Stream in 2007 thus indicating additional inter-annual variations. It is not known whether the variations observed 2007 are a permanent feature and whether they are related to the absence of Pacific waters during that time. The planned comprehensive and quantitative evaluation of freshwater and Pacific water in the Arctic Ocean halocline will thus help to further understand the impact and the potential feedbacks of the Arctic Ocean hydrography on Arctic and global climate change.