Estuarine air-Sea CO2 Fluxes: Evaluating the Impact of Climatological Drivers Spanning Multiple Temporal Scales using Ships-of-Opportunity and Remote Sensing

OCE-0726989河口是地球上最具生产力和活力的水生生态系统之一。由于它们覆盖了世界各地的海岸线，河口在区域和全球C自行车运动中发挥着关键作用。然而，代表河口主要新陈代谢过程总和的河口大气-海洋二氧化碳通量受到诸如飓风事件等气候/水文强迫的年内和年际变化的强烈影响。由于时空采样分辨率有限，以前的研究无法确定这些不同尺度的变异性对河口大气-海洋二氧化碳通量的影响。在这项研究中，来自北卡罗来纳大学教堂山分校和俄勒冈州立大学的跨学科团队已经聚集在一起，量化了美国第二大河口的大气-海洋二氧化碳通量，并对这些通量的环境控制进行了评估和量化。北卡罗来纳州的纽兹河-帕米利科海湾河口系统(NRE-PS)位于迅速扩张的城市和农业活动的下游，在过去十年中有五次2级或更高级别的飓风在其分水岭登陆。此外，该系统的小潮特性和较长的水停留时间(2个月)使其成为研究河口大气-海洋二氧化碳通量的理想选择。NRE-PS的额外优势是持续的、空间和时间上密集的长期观测计划，这些计划将作为补充环境数据的来源；Neuse River建模和监测计划(MODMON)，以及基于渡口的连续监测计划(FerryMon)。NRE-PS大气-海洋二氧化碳通量的稳健评估将通过装备一艘小型考察船和三个北卡罗来纳州部门来完成。利用二氧化碳分压(PCO2)传感器对运输渡轮进行监测，从而能够全年、高时空分辨率地表征地表二氧化碳分压。还将提供遥感(每3天一次)表面生物地球化学数据，这些数据是由美国环保局与研究人员正在进行的合作项目产生的。除了解决海-气通量问题外，该项目的数据还将加强现有的河口生物地球化学机械模型，该模型用于研究营养物质和水文强迫之间的联系，以及全系统的碳和氧气动态。这一努力与在其他平行监测计划期间收集的数据的综合将对评估生态系统对极端气候事件(如干旱和预测的大西洋飓风活动上升)的反应将是非常宝贵的。就更广泛的影响而言，NRE-PS体现了影响沿海边缘的人类和气候扰动的典型症状，因此该项目的结果有可能适用于世界各地的生产性河口生态系统。该项目还将为博士后研究人员、研究生和本科生提供多样化的教育机会，他们将积极参与现场和实验室组成部分，并鼓励他们开展独立研究项目。北卡罗来纳大学和地区性大学的NSF支持的暑期研究生前研究体验计划(SPGRE)将为学生提供暑期实习机会。最后，高中生和教师将在暑期实习期间受聘为实习生，让他们获得一系列新的经验和知识，带回课堂。

OCE-0726989Estuaries are among the most productive and dynamic aquatic ecosystems on Earth. Because they cover extensive areas of coastlines worldwide, estuaries play key roles in regional and global C cycling. However, estuarine air-sea CO2 fluxes, which represent the sum of the major metabolic processes in the estuary, are strongly influenced by intra- and interannual variability in climatological/hydrological forcings such as hurricane events. Because of limited spatial-temporal sampling resolution, previous studies have not been able to determine the impact of these different scales of variability on estuarine air-sea CO2 fluxes. In this research, an interdisciplinary team from the University of North Carolina at Chapel Hill and Oregon State University has been assembled to quantify air-sea CO2 fluxes in the nation's 2nd largest estuary, and to evaluate and quantify environmental controls upon those fluxes. North Carolina's Neuse River-Pamlico Sound estuarine system (NRE-PS) is downstream of rapidly expanding urban and agricultural activities and has had five category 2 or higher hurricanes make landfall in its watershed in the past decade. Additionally, the system's microtidal nature and long water residence time (2 mo) make it ideal for a study on estuarine air-sea CO2 fluxes. The NRE-PS has the added advantage of ongoing, spatially and temporally intense, long-term observational programs that will serve as sources of complementary environmental data; the Neuse River Modeling and Monitoring Program (ModMon), and a ferry-based continuous monitoring program (FerryMon). Robust evaluation of NRE-PS air-sea CO2 fluxes will be accomplished by outfitting a small research boat and three N.C. Dept. of Transportation ferries with CO2 partial pressure (pCO2) sensors, thereby allowing for year-round, high spatial-temporal resolution characterization of surface p CO2. Remotely-sensed (every 3 d) surface biogeochemical data, generated by an ongoing collaborative project with researchers at the U.S. EPA, will also be available. In addition to addressing air-sea fluxes, the data from this project will enhance an existing mechanistic biogeochemical estuarine model that is used to investigate linkages between nutrient and hydrologic forcings, and system wide C and O2 dynamics. This effort, in conjunction with synthesis of data collected during the other parallel monitoring programs, will be invaluable for assessing the ecosystem response to extreme climatological events such as droughts and a predicted rise in Atlantic hurricane activity. In terms of broader impacts, the NRE-PS exemplifies the classic symptoms of human and climatological perturbations impacting the coastal margin and so this project's results have the potential to apply to productive estuarine ecosystems worldwide. This project will also provide diverse educational opportunities for post-doctoral researchers, graduate students, and undergraduate students, who will be actively engaged in field and laboratory components and encouraged to develop independent research projects. The NSF-supported Summer Pre-graduate Research Experience Program (SPGRE) at UNC-CH and regional universities educating predominantly under-represented and minority groups will provide students for summer internships. Finally, high school students and teachers will be employed as interns during the summer field season, giving them a range of newfound experiences and knowledge to bring back to the classroom.