Collaborative Research: United States University CLOUD (Cosmics Leaving OUtdoor Droplets) Consortium Membership

该项目将支持卡内基梅隆大学、加州理工学院和科罗拉多大学博尔德分校继续成为欧洲核子研究中心云联盟的成员，以研究推动地球大气中新粒子形成和增长的化学和物理。Cloud是一个最先进的26立方米不锈钢密封室，可以精确控制温度和相对湿度。云的新研究将集中于研究产生极低挥发性有机化合物的化学机制，这些有机化合物能够成核并凝聚成新成核的颗粒。目标环境包括自然(森林和海洋)和污染(城市)条件，以及自由对流层特有的寒冷温度。计划在今后3年进行的研究包括以下方面：(1)在自由对流层发现的条件下第一代有机氧化产品的老化；(2)测量和模拟有机氧化以及无机硫、氮和碘氧化中的关键自由基中间体，以及有机和无机系统之间的相互作用；(3)测量和模拟蒸气以及10 nm以下带电和中性粒子之间的相互作用，以约束关键的微物理术语；(4)将云结果传播到大气模型，测试其解释实地测量的能力，了解改进对气溶胶辐射强迫模型的影响。除了提供所需的财团费用外，该项目还将支持运费和差旅到云的实验活动以及相关的财团会议和数据研讨会。与该项目相关的博士后和博士后学生(由其他奖项支持)被纳入一个由学生和高级研究人员组成的国际合作网络，这些学生和高级研究人员在气溶胶和大气化学研究方面与一些最受尊敬的科学家合作。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project will support the continued membership of Carnegie Mellon University, the California Institute of Technology, and the University of Colorado at Boulder in the CLOUD consortium at CERN to study the chemistry and physics that drive new-particle formation and growth in Earth's atmosphere. CLOUD is a state-of-the-art 26 cubic meter stainless-steel chamber with precise control over temperature and relative humidity. The new research at CLOUD will focus on the study of chemical mechanisms that generate extremely low volatility organic compounds capable of nucleating and condensing onto freshly nucleated particles. Target environments include natural (both forest and marine) and polluted (urban) conditions, as well as cold temperatures characteristic of the free troposphere. Planned research over the next 3 years, includes studies of: (1) aging of first-generation organic oxidation products under conditions found in the free troposphere; (2) measurement and modeling of key radical intermediates in organic oxidation and also inorganic sulfur, nitrogen, and iodine oxidation, as well as interaction between organic and inorganic systems; (3) measurement and modeling of interactions among vapors and both charged and neutral particles below 10 nm to constrain key microphysical terms; and (4) propagating CLOUD results to atmospheric models, testing their capability to explain field measurements, and understanding the implications of improvements to models for aerosol radiative forcing. In addition to providing the required consortium fee, this project will support shipping and travel to CLOUD experimental campaigns and associated consortium meetings and data workshops. Both doctoral and postdoctoral students associated with the project (supported by other awards) are integrated into an international collaborative network of students and senior researchers who work with some of the most highly regarded scientists in the study of aerosols and atmospheric chemistry.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.