The Impact of Subsurface Fluid Advection on Coastal Ocean Chemistry

海底地下水排放（SGWD）对近岸地区各种化学循环和生物地球化学过程的影响是相当显著的。然而，很难获得量化和化学表征这些地下水通量的数据，海洋和水文科学也缺乏这些数据。PI Moore已经表明，确定SGWD规模的关键是测量寿命较短的镭同位素223Ra和224Ra，以及寿命较长的226Ra。与第二个PI Shaw的合作，增加了测量Ba和稳定微量元素的重要专业知识，使PI能够更好地评估这些地下水通量对海洋科学、水文科学和沿海管理界更感兴趣的各种微量元素和营养素的影响。PI建议使用区域抽样方法对地下水的通量和输入设定界限。在项目期间，将在北卡罗莱纳和佛罗里达之间的南大西洋湾的三个主要邮轮上进行实地取样。建议缩短巡航时间以应对特定的干旱、风暴或降雨事件。还建议利用这些研究地点附近的现有水井进行地下水调查。总的来说，他们独特的示踪测量和辅助数据的结合将使PI能够评估地下水通量对沿海海洋的影响，以及对这些通量的强度和组成的重要控制。

Moore (OCE-9712298) ABSTRACT Moore, Shaw- OCE 9711298 The impact of submarine groundwater discharges (SGWD) on the coastal ocean has been suggested to be quite significant for a variety of chemical cycles and biogeochemical processes in the near shore region. Data however to quantify and chemically characterize these groundwater fluxes are difficult to obtain and are lacking in ocean and hydrological sciences. The lead PI Moore has already shown that the key to determining the scale of SGWD are measurements of short-lived radium isotopes, 223Ra and 224Ra, and the longer lived 226Ra. The association with the second PI Shaw, adds the important expertise to measure Ba and stable trace elements, so that the PI's can better evaluate the influence of these groundwater fluxes on a broad range of trace elements and nutrients that are of wider interest to the marine sciences, hyrological sciences and coastal management communities. The PI's propose to place bounds on the fluxes and inputs of groundwaters using a regional sampling approach. During the project, field sampling will be conducted on three major cruises in the South Atlantic Bight between North Carolina and Florida. Shorter cruises are proposed to respond to specific drought, storm or rainfall events. Groundwater investigations utilizing existing wells near these study sites are also proposed. Overall, the combination of their unique tracer measurements and ancillary data will allow the PI's to evaluate the impact of goundwater fluxes on the coastal oceans, and the important controls on the strengths and composition of these fluxes.