Identifying the Origins of Summertime Arctic Cloud Condensation Nuclei Using Online Fine Aerosol Composition Measurements

云在北极的辐射收支和气候中起着至关重要的作用，但形成这些云滴的粒子的来源却相对未知。这个研究项目将提供一个机会，在北冰洋的破冰船上对微观粒子进行专门的测量。通过了解云粒子的来源，科学家们将能够更好地确定在海冰减少的世界里，云的条件是否会发生变化，从而改善对这个世界关键地区气候的长期预测。项目期间还将开展教育和外展活动，包括在研究巡航期间开设在线照片博客。研究小组将调查夏季北冰洋高纬度地区细颗粒气溶胶和云凝结核的起源。现场测量将在2018年8月至9月期间由瑞典破冰船奥登号进行。热解吸化学电离质谱仪将用于测量环境尺寸分辨率为10-200nm直径的气溶胶的组成，针对积聚，艾特肯和成核模式。总环境亚微米气溶胶也将使用颗粒进液采样器（PILS）收集，随后离线分析。该项目的目标是测量生物多糖物质、海盐、其他有机物和其他盐类对北极气溶胶的相对贡献，以尺寸为基础。一个成功的项目将确定产生不同大小气溶胶的过程，从而能够推断该地区最重要的CCN来源。

Clouds play a critical role in the radiation budget and climate of the Arctic, but the origin of the particles on which these cloud droplets form is a relative unknown. This research project will provide an opportunity to take specialized measurements of microscopic particles onboard an ice breaker in the Arctic Ocean. By understanding the sources of cloud particles, scientists will be better able to determine whether cloud conditions will change in a world with less sea ice, and thus improve long-term forecasts of climate in this critical part of the world. Education and outreach activities will also be conducted during the project, including an online photo blog during the research cruise.The research team will investigate the origin of fine particle aerosols and cloud condensation nuclei over the summertime high Arctic Ocean. Field measurements will be taken from the Swedish icebreaker Oden during August-September 2018. The Thermal Desorption Chemical Ionization Mass Spectrometer will be deployed to measure the composition of ambient size-resolved 10-200nm diameter aerosols, targeting the accumulation, Aitken and nucleation modes. Total ambient sub-micron aerosols will also be collected using a Particle into Liquid Sampler (PILS) and subsequently analyzed offline. The goal of the project is to measure the relative contributions to Arctic aerosol of biogenic polysaccharide material, sea salt, other organics, and other salts, on a size-resolved basis. A successful project would result in determining what processes are responsible for aerosols of different sizes, which would lead to the ability to infer the most important CCN sources in the region.