Impact of diapycnal mixing on the saturation state of argon in the subtropical North Pacific
Impact of diapycnal mixing on the saturation state of argon in the subtropical North Pacific
复制标题
北太平洋副热带地区二重混合对氩饱和状态的影响
DOI：
10.1029/2006gl029209
复制
发表时间：
2007
影响因子：
5.2
通讯作者：
R. Hamme
中科院分区：
文献类型：
--
作者：
T. Ito;C. Deutsch;S. Emerson;R. Hamme
深重混合在海洋的物理和生物地球化学过程中发挥着重要作用，但示踪剂混合的速率尚未得到充分量化。理论分析预测，二重混合应以与二重扩散率成比例的速率提高温跃层中稀有气体的饱和状态。我们将该理论应用于通风温跃层中氩气的现有测量，其中饱和状态的增加应与二重混合的综合效应成正比。结合北太平洋时间序列站的氩气观测数据和氟利昂通风年龄，我们初步估计区域层密扩散率为 0.35 ± 0.21 10−4 m2s−1。不确定性的主要来源包括空间和时间变化以及稀疏采样。通过测量从等重露头到内部环流的横断面中的几种稀有气体，可以显着减少这些不确定性。
Diapycnal mixing plays an important role in both physical and biogeochemical processes in the oceans, yet the rate of tracer mixing has not been adequately quantified. A theoretical analysis predicts that diapycnal mixing should raise the saturation state of noble gases in the thermocline, at a rate proportional to diapycnal diffusivity. We apply this theory to existing measurements of argon in the ventilated thermocline, where the increase in the saturation state should be proportional to the integrated effect of diapycnal mixing. Combining argon observations from time‐series stations in the North Pacific with freon ventilation age, we tentatively estimate the regional diapycnal diffusivity at 0.35 ± 0.21 10−4 m2s−1. Major sources of uncertainty include spatial and temporal variability and sparse sampling. These uncertainties could be significantly reduced using measurements of several noble gases in a transect from the isopycnal outcrop to the interior gyre.