Collaborative Proposal: GEOTRACES Pacific Section: Collection and analysis of atmospheric deposition

在2013年GEOTRACES东太平洋纬向样带期间，向地表水的气溶胶输入将出现梯度，秘鲁附近的气溶胶输入较高，近海气溶胶输入降低。这个纬向剖面与2010年和2011年秋季GEOTRACES北大西洋纬向剖面中发现和采样的高气溶胶沉积区形成鲜明对比。因此，这一太平洋区域代表了在低沉积环境中表征气溶胶和降雨化学的独特机会。来自阿拉斯加大学和佛罗里达州立大学的科学家们计划沿着这条样带收集和描述气溶胶和降雨样本，并将样本分发给社区。在24至48小时的综合基础上收集的散装和大小分级气溶胶样品以及基于事件的降雨样品将进行微量元素和同位素（TEIs）分析，以量化其大气输入。要分析的tei将是铝、钒、铬、锰、铁、钴、镍、铜、锌、镉、铅和钍，以及主要离子钠、镁、钾、钙、硝酸盐、磷酸盐、氯和氟。作为本研究一部分的其他工作包括：(1)气溶胶淋滤，以确定水溶性和超水溶性TEI组分；(2)确定水溶性铁的大小、分馏和氧化还原形态；(3)从其他GEOTRACES科学家那里获得水柱样品的子样品，用于分析感兴趣的TEI，以帮助解释大气沉积数据；(4)与其他机构的研究人员合作，确定大气沉积的特征并加以限制。该项目将通过建立气溶胶溶解度的分数范围和更好地量化全球海洋的沉积，为GEOTRACES计划的总体目标做出贡献。作为该项目的一部分，阿拉斯加大学的一名研究生将得到支持和培训。依靠邮轮博客、电子邮件和项目网站的更新，这位来自阿拉斯加大学的科学家计划继续与阿拉斯加、亚利桑那州和佛罗里达州的学生进行互动，研究结果将被纳入课堂课程，并通过公共宣传和网络传播。

During the 2013 GEOTRACES Eastern Pacific zonal transect, a gradient in aerosol inputs to surface waters will be encountered with higher inputs near Peru and decreasing offshore. This zonal section contrasts sharply to the high aerosol deposition areas found and sampled during the GEOTRACES North Atlantic Zonal Section in the fall of 2010 and 2011. As such, this Pacific section represents a unique opportunity to characterize aerosol and rainfall chemistry in a low deposition environment. Scientists from the University of Alaska and Florida State University plan to collect and characterize aerosol and rainfall samples along this transect, as well as distribute samples to the community. Bulk and size-fractionated aerosol samples collected on a 24 to 48-hour integrated basis and event-based rain samples will be analyzed for trace elements and isotopes (TEIs) to quantify their atmospheric input. The TEIs to be analyzed will be aluminum, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, cadmium, lead, and thorium, as well as the major ions sodium, magnesium, potassium, calcium, nitrate, phosphate, chlorine, and fluorine. Other efforts to be carried out as part of this study include (1) aerosol leaches to determine seawater-soluble and ultrapure-water-soluble TEI fractions: (2) determine the size fractionation and redox speciation of seawater-soluble iron: (3) obtain subsamples of water column samples from other GEOTRACES scientists for the analysis of the TEIs of interest to help interpret the atmospheric deposition data; and (4) collaborate with researchers from other institutions to characterize and constrain estimates of atmospheric deposition. This project will contribute towards the overall goal of the GEOTRACES Program by establishing the range of fractional aerosol solubility and better quantify deposition across the global ocean. One graduate student from the University of Alaska would be supported and trained as part of this project. Relying on a cruise blog, email, and project website updates, the scientist from the University of Alaska plans to continue her interactions with students in Alaska, Arizona, and Florida and results from the study would be incorporated into class curricula, as well as disseminated via public outreach and web dissemination.