Trace Elements and Radionuclides in North Atlantic Precipitation

在过去的10-15年里，大气化学已经从一个主要致力于研究城市污染和空气质量等局部问题的年轻研究学科发展成为一门涉及各种化学物质在半球到全球范围内循环的成熟科学。在很大程度上，这种变化是由于人们日益认识到，人类活动可以对自然对流层造成化学干扰，其规模远远超出当地的关注范围。众所周知的例子包括某些氮化合物、铅和其他重金属、人工放射性核素、一些合成有机物质、某些形成酸的物种、二氧化碳和甲烷的区域到全球浓度的变化。大气中的这些化学变化通常可以扩展到远离原始来源地区的地球土壤、海洋和生物群。它们可能导致地球气候的变化，重要的营养循环的变化，并对地球上的公共健康和生活质量产生重大影响。大气/海洋化学实验（AEROCE）将是一个以北大西洋区域为中心的协调的多机构大气和海洋化学研究项目。欧空局项目的最终目标将是发展在北大西洋上空海洋对流层观测到的大陆衍生物种的预测能力。在AEROCE中，地点的选择和测量方案是由建模人员和现场实验人员共同制定的。AEROCE项目的这一要素涉及检查北大西洋降水中的微量元素（Al、As、Cd、Cu、Fe、Mn、Ni、Sb、Se和Zn），以评估大气运输和大陆源物质向海洋的沉积。之所以选择北大西洋，是因为它被这些元素相对强烈的自然和人为来源所包围。对降水进行采样，因为它主要负责海洋对流层的微量元素沉积。这些数据将与相关气溶胶的数据进行比较，以帮助确定北大西洋上空微量元素的来源，帮助确认相关气团轨迹信息，并帮助评估海洋降水去除微量元素的程度。相应的湿通量数据将揭示降水对北大西洋微量元素收支的贡献。具体而言，这些湿大气通量占全球海洋通量的很大一部分，并最终影响海洋表层水的生物生产力。为了达到研究目标，P.I.该项目将使用一套精心挑选的微量元素，采用综合收集程序，通过相互校准和质量控制协议确保数据准确，并与其他研究结果充分整合。

Over the past 10-15 years atmospheric chemistry has evolved from a young research discipline devoted primarily to local problems of urban pollution and air quality to a mature science concerned with the hemispheric to global scale cycling of a wide variety of chemical species. To a large extent this change has resulted from an increasing realization that human activities can cause chemical disturbances to the natural troposphere on scales far beyond local concerns. Well-known examples include changes in the regional-to-global concentrations of certain nitrogen compounds, lead and other heavy metals, artificial radionuclides, a number of synthetic organic substances, certain acid-forming species, carbon dioxide and methane. These chemical changes in the atmosphere can often extend to the earth's soils, oceans, and biota far from the original source region. They can result in alterations in the earth's climate, changes in vital nutrient cycles, and impact significantly on the public health and quality of life on earth. The Atmosphere/Ocean Chemistry Experiment (AEROCE) will be a coordinated multi-institutional atmospheric and marine chemistry research project centered in the North Atlantic region. The ultimate goal of the AEROCE project will be the development of a predictive capability for the continentally derived species observed in the marine troposphere over the North Atlantic. The selection of sites and the measurement protocol in AEROCE has been developed jointly by modelers and field experimentalists. This element of the AEROCE project is concerned with examining trace elements (Al, As, Cd, Cu, Fe, Mn, Ni, Sb, Se, and Zn) in precipitation to the North Atlantic to assess atmospheric transport and deposition of continentally derived material to the sea. The North Atlantic is chosen because it is surrounded by relatively strong natural and anthropogenic sources of these elements. Precipitation is sampled because it is largely responsible for trace element deposition from the marine troposphere. The data will be compared to that in associated aerosols to help identify sources of trace elements over the North Atlantic, to help confirm associated air mass trajectory information, and to help evaluate the extent of trace element removal by marine precipitation. The corresponding wet flux data will reveal the contribution of precipitation to North Atlantic trace elements budgets. Specifically, these wet atmospheric fluxes comprise a significant portion of the global ocean flux and ultimately influence the biological productivity of oceanic surface waters. To meet the research objectives, the P.I.'s will utilize a carefully selected suite of trace elements, employ synoptic collection procedures, ensure accurate data through intercalibration and quality control protocols, and integrate fully with other research results.