Trace Element Analysis of Aerosol and Seawater Samples Collected on the A16N, P02, and P16S CLIVAR Cruises

CLIVAR重复水文计划的微量金属部分提供了一个前所未有的机会，以确定总的和可溶性气溶胶铁（Fe）和铝（Al）的分布，并测量溶解和颗粒铁和铝在整个海洋盆地的水柱剖面。 在一度剖面间距收集的样品揭示了溶解和颗粒状Fe和Al的分布中的精细尺度特征，这是以前未被认识到的。 由于对开发海洋过程的地球化学示踪剂（如GEOTRACES）的广泛兴趣，使用三次考察的存档样品来确定和量化控制其他微量元素分布及其对不断变化的环境条件的敏感性的过程是有效的。来自佛罗里达州立大学的一名研究人员将分析存档的气溶胶过滤器、存档的（酸化的）气溶胶沥滤溶液和存档的（酸化的）海水样本，这些样本是在三次CLIVAR巡航（A16 N-冰岛到巴西; P02-日本到圣地亚哥; P16 S-塔希提岛到新西兰）期间收集的，用于痕量金属、准金属和稀土元素，并完成Fe和Al数据集。 将对气溶胶样品进行消化，并使用高分辨率电感耦合等离子体质谱法（HR-ICP-MS）分析至少42种微量元素。 将分析蒸馏的去离子水气溶胶浸提溶液中的这些相同元素和硅。 将使用一种新开发的多元素同位素稀释高分辨率电感耦合等离子体质谱法，在使用一个小型8-羟基喹啉柱进行萃取和洗脱之后，对水柱样本（和海水气溶胶沥滤溶液）进行铁、镍、铜、锌、镉和铅分析。 从这些溶解微量元素和总的和可溶性气溶胶微量元素的全流域部分收集的信息将导致更好地了解全球海洋生物地球化学循环如何运作。 铁的数据将直接输入耦合的海洋/大气营养和碳循环模型，并允许更准确地预测大气铁沉积在世界主要海洋盆地的各种地理区域中所起的作用。 此外，这位科学家将参加定于2006年2月至5月进行的CLIVAR重复水文学巡航的P16 N航段（塔希提-阿拉斯加），这项工作将完成横跨太平洋的南北段。 至于更广泛的影响，这项研究将有助于实现即将到来的GEOTRACES计划的目标，大大加强全球微量元素数据库，这将导致更好地了解海洋地球化学循环，数据将改善耦合海洋/大气模型。 两名研究生将参加即将到来的P16 N CLIVAR重复水文学巡航，并将获得分析气溶胶和海水样品中微量元素的经验。

The trace metals component of the CLIVAR Repeat Hydrography program has provided an unprecedented opportunity to determine the distributions of total and soluble aerosol iron (Fe) and aluminum (Al) and for measuring the water column profiles of dissolved and particulate Fe and Al across entire ocean basins. The samples collected at one-degree profile spacing have revealed fine-scale features in the distributions of dissolved and particulate Fe and Al that were previously unrecognized. Because of the broad interest in developing geochemical tracers of oceanographic processes (e.g. GEOTRACES), it is effective to use the archived samples from the three cruises to identify and quantify the processes that control the distribution of other trace elements and their sensitivity to changing environmental conditions. A researcher from Florida State University will analyze archived aerosol filters, archived (acidified) aerosol leach solutions, and the archived (acidified) seawater samples collected during three CLIVAR cruises (A16N-Iceland to Brazil; P02-Japan to San Diego; and P16S-Tahiti to New Zealand) for trace metals, metalloids, and rare earth elements, and complete the Fe and Al data set. Aerosol samples will be digested and analyzed for at least 42 trace elements using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). The distilled, deionized water aerosol leach solutions will be analyzed for these same elements plus silicon. Water column samples (and the seawater aerosol leach solutions) will be analyzed for iron, nickel, copper, zinc, cadmium and lead using a newly developed method for multi-element isotope dilution high resolution inductively coupled plasma mass spectrometry after extraction and elution using a small 8-hydroxyquinoline column. Information gathered from these basin-wide sections of dissolved trace elements and total and soluble aerosol trace elements will lead to a better understand of how global ocean biogeochemical cycles operate. The iron data will feed directly into coupled ocean/atmosphere nutrient and carbon cycling models, and permit a more accurate prediction of the role played by atmospheric iron deposition across various biogeographic zones of the world's major ocean basins. In addition, the scientist will participate in the P16N leg (Tahiti-Alaska) of the CLIVAR Repeat Hydrography cruise scheduled for February through May of 2006, an effort that will complete the N-S section across the Pacific Ocean. As regards broader impacts, this study will contribute to the goals of the upcoming GEOTRACES Program, greatly enhance the global trace element database that will lead to an improved understanding of oceanic biogeochemical cycles, and the data will improve coupled ocean/atmosphere models. Two graduate students will participate in the upcoming P16N CLIVAR Repeat Hydrography cruise and will also gain experience in analyzing aerosol and seawater samples for trace elements.