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

该项目支持卡内基-梅隆大学和加州理工学院继续加入欧洲核子研究中心的CLOUD联盟，并为科罗拉多大学博尔德分校提供新成员资格。云（宇宙离开室外液滴）实验设施可能是世界上最复杂的研究大气新粒子形成的实验。它是用来在高度控制的超清洁条件下测量新粒子形成的。CLOUD是一个国际成员资助的财团，支持该实验的维护和运行。成员从他们的国家机构筹集研究经费参与。每年在CERN进行1-2次精心计划的实验，每次持续8-10周。这些活动是在每年两次为期一周的主要联盟会议期间规划和评估的，而更集中的、密集的数据分析是由个人随时进行的，但在每年的过程中，根据分析和解释的需要，也会在几个专门的团队会议上安排和主持。通过skype和其他媒体的虚拟团队会议正在进行和持续。除了提供所需的联盟费用外，该项目还将支持参加CLOUD实验活动以及相关的联盟会议和数据研讨会的运输和旅行。与该项目相关的博士和博士后学生将被整合到一个由学生和高级研究人员组成的国际合作网络中，这些研究人员是气溶胶科学和大气化学领域最受尊敬的研究人员。他们将在开展国际合作研究方面接受宝贵的培训。CLOUD实验的主题引起了国内和国际的高度关注。气溶胶与云的相互作用是对气候强迫和气候敏感性的认识中最大的不确定性来源之一。CLOUD实验证实离子可以稳定成核团簇，并且对于弱结合团簇（如氨硫酸、含硫酸的有机物和纯有机物），离子可以根据条件提高3-100倍的成核率。在本项目期间，计划开展CLOUD-13、CLOUD-14、CLOUD-15三个战役。这些活动将集中在以下广泛的主题：有机氧化化学在新粒子形成和生长中的作用；城市新粒子的形成；海洋大气中新粒子的形成；以及电荷在云滴形成和冰晶成核中的作用（如果有的话）。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project supports the continued membership in the CLOUD consortium at CERN, by Carnegie-Mellon University and the California Institute of Technology, and provides new membership for the University of Colorado at Boulder. The CLOUD (Cosmics Leaving OUtdoor Droplets) experimental facility is likely the world's most sophisticated experiment addressing atmospheric new-particle formation. It was constructed to measure new particle formation under highly controlled, ultra-clean conditions.CLOUD is an international member-funded consortium supporting the maintenance and operation of the experiment. Members raise research funding from their national agencies to participate. Experiments are conducted at CERN during 1-2 carefully planned campaigns per year, each lasting 8-10 weeks. These campaigns are planned, and data are assessed, during two major week-long consortium meetings each year, while more focused, intensive data analysis is carried out at all times by individuals, but also in several focused team meetings scheduled and hosted on an ad-hoc basis during the course of each year as analysis and interpretation require. Virtual team meetings via skype and other media are ongoing and continuous.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. The doctoral and postdoctoral students associated with the project will be integrated into an international collaborative network of students and senior researchers who are among the most highly regarded in aerosol science and atmospheric chemistry. They will receive invaluable training in the conduct of international collaborative research.The subject of the CLOUD experiments is of high national and international interest. Aerosol-cloud interactions are among the largest sources of uncertainty in the understanding of climate forcing and climate sensitivity. CLOUD experiments confirm that ions can stabilize nucleating clusters, and that, for otherwise weakly bound clusters (such as ammonia sulfuric acid, organics with sulfuric acid, and pure organics), ions can enhance nucleation rates by factors of 3-100 depending on conditions. During the period of this project, three campaigns, CLOUD-13, CLOUD-14, and CLOUD-15, are planned. The campaigns will focus on the following broad topics: the role of organic oxidation chemistry in new-particle formation and growth; new-particle formation in urban areas; new-particle formation in the marine atmosphere; and the role, if any, of charge in cloud-droplet formation and ice-crystal nucleation.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.