Characterization of atmospheric iron over and its fluxes to the Southern Ocean through shipboard measurements

摘要南大洋高营养、低叶绿素区域通常由生物有效铁(Fe)缺乏来解释。人们提出并研究了南大洋/南极大陆边缘铁的各种局部来源。在远离明显局部化的陆地尘源的地区，没有很好地观察到气溶胶Fe的海气沉积、大气Fe的粒度分布和气溶胶成分的变化，包括可能影响Fe和微量营养素的生物可利用性的其他大气成分。本项目旨在对从上海到中山站途经南大洋的中国破冰船(R/V雪龙)进行船上大气采样和分析，测量南极散装和粒度分离气溶胶样品的化学、物理和形态特征，用毛细管波导法测定铁含量，用质谱仪(ICPMS)测定元素组成，以及相应的水溶性组分。当遇到降水样本时，也将对其进行分析，以得出湿沉积通量。气溶胶粉尘产品的卫星遥感和化学传输建模方法也将用于数据解释。

Abstract High nutrient low chlorophyll regions of the Southern Ocean are conventionally explained by lack of bioavailable iron (Fe). Various localized sources of Fe in the Southern Ocean/Antarctic continental margins have been proposed and studied. In areas removed from obviously localized terrestrial dust sources, air-sea deposition of aerosol Fe, the particle size distribution of atmospheric Fe and the variability of aerosol composition, including other atmospheric constituents that may affect the bioavailability of Fe and micronutrients, is not well observed. This project seeks to conduct shipboard atmospheric sampling and analysis from a Chinese ice breaker (R/V Xue Long) passing through the Southern Ocean on route from Shanghai to Zhongshan Station, Antarctica Bulk aerosol and size segregated aerosol samples will be measured for their chemical, physical and morphological properties, Fe content by capillary waveguide spectrophotometry, elemental composition by mass spectrometry (ICPMS), along with corresponding water soluble fractions. Precipitation samples, when encountered, will also be analyzed to derive wet deposition fluxes. Satellite remote sensing of aerosol dust products and chemical transport modeling approaches will also be used in data interpretation.