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

CLIVAR重复水文学计划中的痕量金属成分为确定气溶胶中总和可溶的铁(Fe)和铝(Al)的分布以及测量整个大洋盆地中溶解和颗粒态的铁和铝的水柱剖面提供了前所未有的机会。在一度剖面间距下采集的样品在溶解和颗粒Fe和Al的分布中显示出以前未被识别的细微尺度特征。由于人们对开发海洋过程的地球化学示踪剂(例如GEOTRACES)有着广泛的兴趣，利用三个航次的存档样本来确定和量化控制其他微量元素的分布及其对环境条件变化的敏感性的过程是有效的。佛罗里达州立大学的一名研究人员将分析三次CLIVAR航次(A16N-冰岛至巴西；P02-日本至圣地亚哥；P16S-大溪地至新西兰)期间收集的存档气溶胶过滤器、存档(酸化)气溶胶淋滤液和存档(酸化)海水样本中的痕量金属、类金属和稀土元素，并完成Fe和Al数据集。气溶胶样品将被消化，并使用高分辨率电感耦合等离子体质谱(HR-ICP-MS)分析至少42种微量元素。蒸馏、去离子水气溶胶浸出液将分析这些相同的元素和硅。水柱样品(和海水气溶胶浸出液)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方法分析铁、镍、铜、锌、镉和铅，然后使用小型8-羟基喹啉柱进行提取和洗脱。从这些盆地范围的溶解微量元素以及总和可溶气溶胶微量元素部分收集的信息将有助于更好地了解全球海洋生物地球化学循环是如何运作的。铁数据将直接输入海洋/大气营养和碳循环耦合模型，并允许更准确地预测世界主要海洋盆地不同生物地理区域的大气铁沉积所起的作用。此外，这位科学家将参加定于2006年2月至5月进行的CLIVAR重复水文测量巡航的P16N航段(塔希提岛-阿拉斯加)，这一努力将完成横跨太平洋的N-S航段。至于更广泛的影响，这项研究将有助于实现即将到来的地球空间研究方案的目标，极大地增强全球微量元素数据库，从而增进对海洋生物地球化学循环的了解，并将改进海洋/大气耦合模型。两名研究生将参加即将举行的P16N CLIVAR重复水文学巡游，并将在分析气溶胶和海水样本中的痕量元素方面获得经验。

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.