MRI: Development of a Cavity Ring-Down Sensor for Real-Time Measurement of Atmospheric Mercury Concentrations and Fluxes

该项目由《2009年美国复苏和再投资法案》（公法111-5）资助，将开发一种实时、灵敏的大气汞测量传感器，以解决当前传感器时间分辨率低造成的大气汞测量不确定性。该项目以沙漠研究所开发的实验室原型汞传感器为基础，旨在：（1）开发一种快速响应的空腔衰荡传感器，该传感器具有开放和封闭路径空腔，用于测量大气汞;（2）部署和实地测试该传感器，包括首次应用涡动协方差法测量汞通量。目标是一个稳定的传感器，易于部署，并在地面和高海拔研究站安全运行。在现有原型的基础上，将开发具有基本设计改进和关键技术特征的传感器，包括改进的镜面反射率、用于差分开/关吸收线测量的高频波长调谐、自动波长锁定和优化设计，用于测量大气汞浓度和通量的新传感器将大大提高检测极限，并促进现场部署。在大气汞的分布和动态方面的知识进步，大气汞是淡水水生生态系统汞输入的主要来源。更好地量化汞的来源、汇、转化和迁移模式，对于监管机构保护人类和生态系统免受这种剧毒的危害至关重要。该项目将涉及高中，本科，研究生和博士后学者。教育部分将通过参与现有的NSF资助的项目针对代表性不足的群体，这些项目将（1）为来自几个合作机构的不同本科生群体提供研究经验，包括几所历史上的黑人大学和西班牙裔服务机构;和（2）加强参与研讨会计划，辅导，并促进与大气科学和气象学女教师的合作。进一步的教育活动将包括加强目前与当地高中的伙伴关系，并在里诺的内华达州大学的大气仪表课程中展示传感器的开发。将通过出版物和专题介绍向科学界进行宣传和传播。将通过新闻稿、DRI机构出版物和网站向公众宣传。将继续为正在开发的仪器进行技术转让。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).This project will develop a real-time, sensitive sensor for measurement of atmospheric mercury (Hg) to resolve uncertainties in atmospheric Hg measurements imposed by low temporal resolution of current sensors. Based on a laboratory prototype Hg sensor developed at the Desert Research Institute (DRI), this project aims to (1) develop a fast-response cavity ringdown sensor with open- and closed-path cavities to measure atmospheric Hg; and (2) deploy and field-test the sensor, including the first application for Hg flux measurement by means of eddy covariance. The goal is a sensor that is stable, easy to deploy, and safe to operate at ground-based and high-elevation research stations. Building on an existing prototype, a sensor will be developed with fundamental design improvements and key technical features, including improved mirror reflectivity, high-frequency wavelength tuning for differential on/off absorption line measurement, automatic wavelength locking, and optimized design, to significantly improve detection limits and facilitate field deployments.The new sensor for measurement of atmospheric Hg concentrations and fluxes will enable significant advances in knowledge of the distribution and dynamics of atmospheric Hg, the primary source of Hg inputs to freshwater aquatic ecosystems. Better quantification of Hg sources, sinks, transformations, and transport patterns will be critical for regulatory agencies to protect humans and ecosystems from this potent toxin. The project will involve high school, undergraduate, and graduate students and post doctoral scholars. An educational component will be targeted at underrepresented groups through participation in existing NSF-funded projects that will (1) provide research experiences for a diverse group of undergraduate students from several partner institutions, including several Historically Black Universities and Hispanic-serving institutions; and (2) enhance participation in workshop programs, mentoring, and promoting collaboration with women faculty in atmospheric science and meteorology. Further educational activities will include strengthening current partnerships with local high schools and showcasing the sensor development in an atmospheric instrumentation course at the University of Nevada, Reno. Outreach and dissemination to the scientific community will be accomplished through publications and presentations. The general public will be reached through news releases, DRI institutional publications, and Web sites. Technology transfer for the instrument being developed will be pursued.