Multi-tracer study on Arctic Ocean Acidification

对加拿大盆地碳酸钙饱和状态的分布进行了观测。在表层和次表层发现了不饱和水。地表欠饱和水的分布主要由稀释、增温/降温和光合作用决定。对于地下欠饱和水（太平洋冬季水），我们测量了SF6浓度，以估计水团年龄。结果表明，加拿大盆地的PWW平均年龄为~10年，较新的PWW通过3条通道进入盆地。我们还开发了一种利用盐度、温度和氧数据重建碳酸钙饱和状态的方法。重建值与观测值吻合良好。通过将此方法应用于历史观测，我们可以绘制出整个北冰洋碳酸钙饱和状态的地图。此外，我们全年使用系泊海水采样器成功收集海水样本。

We have observed distribution of calcium carbonate saturation state in the Canada Basin. Undersaturated waters were found at the surface and subsurface layers. The distributions of surface undersaturated water were mainly determined by dilution, warming/cooling and photosynthesis. For the subsurface undersaturated water (Pacific Winter Water), we have measured SF6 concentrations in order to estimate water mass ages. Results revealed that mean age of PWW in the Canada Basin is ~10 years and newer PWW is transported in to the basen by 3 pathways. We also developed a method to reconstruct calcium carbonate saturation state from salinity, temperature and oxygen data. Reconstructed values well agreed with observed values. By applying this method to historical observations, we could make a map of calcium carbonate saturation state for the entire Arctic Ocean.Furthermore, we have successfully collected seawater samples throughout the year, by using moored water samplers.