Using excess 3He to estimate Southern Ocean upwelling timescales
Using excess 3He to estimate Southern Ocean upwelling timescales
复制标题
使用过量的 3He 来估计南大洋上升流的时间尺度
DOI：
10.1002/essoar.10502093.1
复制
发表时间：
2020
影响因子：
5.2
通讯作者：
W. Jenkins
中科院分区：
文献类型：
--
作者：
W. Jenkins
使用最近编制的全球海洋溶解氦同位素和氦和氖浓度数据集，我们估计南大洋热液He的库存为3.4 × 0.7 × 10摩尔。假设大部分的热液来源的他是上涌有，我们使用最近的估计全球热液他通量，以确定一个e-折叠的停留时间为62 - 14年，这取决于假设的水团和上涌边界。我们的估计是从流通模型获得的值相媲美。时间尺度是在低端的估计清除溶解铁的寿命（70至270年），这表明在深太平洋的水热源溶解铁的一个显着的部分可能会达到海洋表面的影响新的初级生产。海底热液系统注入了大量的溶解铁，但仍不清楚这种微量元素的哪一部分在化学清除中幸存下来，在南大洋上升到达海面。由于铁是海洋生物生产力所必需的微量营养素，因此了解深水上升到水面所需的时间是很重要的。沿着溶解的铁，氦-3，一种稀有的惰性同位素也被注入深水。由于这种同位素的全球通量已经由大尺度海洋模型独立确定，我们可以通过将其划分为南大洋这种同位素的库存来估计上升流的时间尺度。
Using a recently compiled global marine dataset of dissolved helium isotopes and helium and neon concentrations, we make an estimate of the inventory of hydrothermal He in the Southern Ocean to be 3.4 0.7 x 10 moles. Under the assumption that the bulk of the hydrothermally sourced He is upwelled there, we use recent estimates of the global hydrothermal He flux to determine an e-folding residence time of 62 14 years, depending on assumptions of water mass and upwelling boundaries. Our estimate is comparable to values obtained from circulation models. The time-scale is at the lower end of the estimated scavenging life-time for dissolved iron (70 to 270 years), suggesting that a significant fraction of hydrothermally-sourced dissolved iron in the deep Pacific may reach the surface ocean to influence new primary production. Plain Language Summary Seafloor hydrothermal systems inject significant amounts of dissolved iron, but it remains unknown what fraction of that trace element survives in situ chemical scavenging to upwell in the Southern Ocean to arrive at the sea surface. Since iron a necessary trace-level nutrient for marine biological productivity, knowledge of the time it takes for deep water to rise to the surface is important. Along with dissolved iron, helium-3, a rare, inert isotope is also injected into the deep water. Since the global flux of this isotope has been independently determined by large-scale ocean models, we can estimate the upwelling time-scale by dividing it into the inventory of this isotope in the Southern Ocean.
影响因子：
11.4
作者：
Jenkins, William J.;Doney, Scott C.;Swift, Jim
通讯作者：
Swift, Jim