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

在2013年地球物理观测系统东太平洋地带性样带期间，向地表水的气溶胶输入将出现梯度，秘鲁附近的输入会更高，而近海的输入会减少。这一分区与2010年和2011年秋季在GEOTRACES北大西洋分区期间发现和采样的高气溶胶沉积区形成鲜明对比。因此，这一太平洋部分是描述低沉积环境中气溶胶和降雨化学特征的独特机会。来自阿拉斯加大学和佛罗里达州立大学的科学家计划沿这一样带收集气溶胶和降雨样本并对其进行表征，并将样本分发给社区。将对24至48小时综合收集的散装和分级气溶胶样本以及基于事件的降雨样本进行微量元素和同位素分析，以量化其大气输入。将分析的TEI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。作为本研究的一部分，还将开展的其他工作包括：(1)气溶胶淋滤以确定海水中溶解的和超纯水溶解的TEI组分：(2)确定海水溶解铁的粒度分馏和氧化还原形态；(3)从其他GEOTRACES科学家那里获取水柱样本的亚样，用于分析感兴趣的TEI，以帮助解释大气沉积数据；以及(4)与其他机构的研究人员合作，以确定和限制对大气沉积的估计。该项目将通过确定部分气溶胶的溶解度范围和更好地量化全球海洋的沉积，为实现地球物理轨道系统方案的总体目标作出贡献。阿拉斯加大学的一名研究生将作为该项目的一部分得到支持和培训。依靠邮轮博客、电子邮件和项目网站更新，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.