Dissolved iron in the tropical and subtropical Atlantic Ocean
Dissolved iron in the tropical and subtropical Atlantic Ocean
复制标题
DOI：
10.1029/2005gb002505
复制
发表时间：
2006-03-18
影响因子：
5.2
通讯作者：
Boyle, EA
中科院分区：
文献类型：
--
作者：
Bergquist, BA;Boyle, EA
[1]详细的深度剖面和表面断面的溶解铁（DFe定义为0.4-μ m过滤）进行了调查，在亚热带和热带大西洋的三个邮轮，灰尘沉积变化3个数量级。地表DFe和溶解Mn浓度反映了粉尘沉积趋势，但不成比例的估计输入。使用估计的大气通量的DFe，表面DFe停留时间计算为1至5个月的顺序。深水DFe浓度随水团而变化，取决于它们的来源、年龄和过境途径。在位于赤道系统边缘的一个地点（北纬10度，西经45度），高DFe（> 1 nmol/ kg）与130至1100米深度的氧最小区有关。北大西洋深水（NADW）中的DFe浓度从北大西洋的站点到南大西洋的站点（南纬24.5度，西经37度）降低了30%，并且在南大西洋站点，南极衍生水团中的DFe浓度（类似于0.4 nmol/kg）低于NADW。根据沿着NADW流动路径DFe减少的情况，DFe的深水清除停留时间估计为270 +/- 140年。
[1] Detailed depth profiles and surface transects of dissolved iron (DFe defined by 0.4-mu m filtration) were investigated on three cruises in the subtropical and tropical Atlantic Ocean where dust deposition varied by 3 orders of magnitude. Surface DFe and dissolved Mn concentrations reflected dust deposition trends, but are not proportional to the estimated inputs. Using estimates of the atmospheric flux of DFe, surface DFe residence times were calculated to be on the order of 1 to 5 months. Deepwater DFe concentrations varied with water masses depending on their source, age, and transit pathways. At a site located on the edge of the equatorial system (10 degrees N, 45 degrees W), high DFe (> 1 nmol/ kg) was associated with an oxygen minimum zone at depths of 130 to 1100 m. DFe concentrations in North Atlantic Deep Water (NADW) decreased by 30% from sites in the North Atlantic to a site in the South Atlantic (24.5 degrees S, 37 degrees W), and DFe was lower in the Antarctic derived water masses ( similar to 0.4 nmol/kg) than in NADW at the South Atlantic site. An estimate of deepwater scavenging residence time for DFe was 270 +/- 140 years based on decreasing DFe along the NADW flow path.