U.S. France Cooperative Research: Vertical Profiles of Krypton-85 as an Indicator of Stratosphere-to-Troposphere Exchange Transport

该奖项将支持纽约州立大学奥尔巴尼分校的Mark Kritz博士和法国吉夫苏尔伊维特辐射活动中心的Joseph Sanak博士在大气化学方面的合作研究。该项目的目标是将法国研究团队进行的氪-85测量纳入美国的一个项目，在该项目中，将在加利福尼亚州北部收集氡、臭氧、一氧化碳、水蒸气和气溶胶的垂直剖面。这些观测将被用来记录和研究亚洲地面空气的快速远距离输送，并将有助于验证全球环流和化学输送模型。在这项研究中使用的一架C-41飞机上进行的一系列对流层上层氡测量显示，亚洲边界层空气有系统地、快速地输送到加利福尼亚州附近的对流层上层。这些运输也可能是化学活性物种和气雾剂全球分配和预算的一个重要因素。该计划将获取的廓线将跨越1-11公里的高度范围，并将用于记录和研究对流层中上层的跨太平洋输送。由于它的半衰期很长(10.76年)，北半球来源占主导地位，平流层丰度低，氪-85的测量将是该研究计划的一个有价值的辅助工具。此外，Kr-85的观测本身将显著增加对这种放射性核素的自由对流层观测次数，并将增加我们对其大气分布和行为的了解。自成立以来，法国实验室一直是利用天然放射性核素研究海洋和大气的先驱之一。该项目将受益于萨纳克博士和他的研究团队将在这一主题上提供的大量专业知识。

This award will support collaborative research in atmospheric chemistry between Dr. Mark Kritz, State University of New York at Albany, and Dr. Joseph Sanak, Centre des Faibles Radioactivites, Gif-sur-Yvette, France. The objective of this project is to incorporate Krypton-85 measurements, made by the French research team, into a US program in which vertical profiles of radon, ozone, CO, water vapor and aerosols will be collected over northern California. The observations will be used to document and study episodes of rapid long-range transport of Asian surface-level air, and will aid in the verification of global circulation and chemical transport models. A series of upper tropospheric radon measurements made aboard a C-41 aircraft used in this research revealed systematic, rapid transport of Asian boundary layer air to the upper troposphere near California. These transports could also be a significant factor in the global distribution and budgets of chemically active species and aerosols. The profiles to be acquired in this program will span the altitude range 1-11 km and will be used to document and study trans-Pacific transports in the mid and upper troposphere. Because of its long (10.76 year) half-life, dominance of northern hemisphere sources and low stratospheric abundances, the Krypton-85 measurements will be a valuable adjunct to the research program. In addition, the Kr-85 observations themselves will represent a significant increase in the number of free tropospheric observations of this radionucleide, and will add to our knowledge of its atmospheric distribution and behavior. Since its inception the French laboratory has been among the pioneers in the use of natural radionucleides to study the oceans and atmosphere. This project will benefit from the significant expertise on this topic to be provided by Dr. Sanak and his research team.