Collaborative Research: Antarctic Low Cloud Interaction with Natural Aerosol (ALCINA)

全球气候模式模拟是预测地球未来气候对温室气体浓度变化或入射太阳能变化的响应的最重要工具之一。对南极和南大洋的气候模拟可以通过对低层云的更好的物理表征来改进，低层云对冰表面融化事件和太阳能量传输的不准确性有很大的影响，这降低了天气模式的质量。云模拟中的错误与关于气溶胶的信息不足有关。气溶胶是一种无处不在的微小颗粒，是云滴和云冰晶形成的种子。该项目将在帕尔默站连续18个月收集气溶胶化学和微物理特性数据，同时收集云光学特性数据，对来自海洋和大陆的气溶胶进行采样。为了产生更广泛的影响，实地活动涉及不同的首席科学家和早期职业研究人员，并将通过全球与环境可持续发展学院的南极系列讲座参与公众外展研讨会。该项目的科学活动将通过与加州科学教育者协会的合作，纳入加州下一代科学标准。该项目将部署先进的气溶胶采样设备、云遥感和地表辐射仪器，这些仪器将在帕尔默站运行更长时间。这些新的观测涵盖了包括两个南方夏季在内的所有季节，将为气候模式评估和改进提供可靠的气溶胶-云相互作用（ACI）统计数据。气溶胶特性测量包括大小分布、云凝结核（CCN）和冰成核粒子（INPs）的数量浓度、化学成分（包括矿物、硫酸盐、海盐和有机物）以及DNA测序得出的微生物群落结构。由于生物活性的强烈季节性循环和气团起源的变化，观测结果将跨越气溶胶数量、浓度和化学成分的数量级变化。这些新的测量还将区分藻华和大陆尘埃对INPs的影响，目前南极洲的数据非常缺乏。大气观测包括近红外光谱测量云中液态水含量、有效液态水水滴和冰晶粒径、云底高度和几何厚度以及地表能收支分量。这些观测将由NASA中分辨率成像光谱辐射计（MODIS）、NASA云和陆地高程卫星（ICESat-2）以及Soumi国家极轨伙伴关系（SNPP）和NOAA-20卫星上的可见红外成像辐射计套件（VIIRS）对云特性的卫星遥感进行补充。该项目由大气和地球空间科学部共同资助。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。

Global climate model simulations are one of the most important tools for predicting Earth’s future climate in response to changing greenhouse gas concentrations or changes in incoming solar energy. Climate simulations over Antarctica and the Southern Ocean can be improved by better physical representation of low-level clouds, which have large impacts on ice surface melt events and inaccuracies in solar energy transmission, which degrades weather models. Errors in cloud simulations have been linked to insufficient information about aerosols - the ubiquitous microscopic particles that seed cloud droplet and cloud ice crystal formation. This project will collect data on aerosol chemical and microphysical properties simultaneously with cloud optical properties at Palmer Station continuously for 18 months, sampling aerosols sourced from both the ocean and from the continent. For broader impacts, the field campaigns involve diverse lead scientists and early career researchers and will engage in public outreach seminars through the School of Global and Environmental Sustainability’s Antarctic Lecture Series. Scientific activities from this project will be incorporated into the California Next Generation Science Standards through a partnership with the California Association for Science Educators.This project will deploy a combination of advanced aerosol sampling equipment and cloud remote sensing and surface radiation instruments that will operate for an extended duration at Palmer Station. Encompassing all seasons including two austral summers, these new observations will yield robust aerosol-cloud interaction (ACI) statistics for climate model evaluation and improvement. Aerosol property measurements include size distributions, number concentrations of cloud condensation nuclei (CCN) and ice nucleating particles (INPs), chemical composition including mineral, sulfate, sea salt and organics, and microbial community structure from DNA sequencing. The observations will span orders of magnitude changes in aerosol number concentrations and chemical constituents resulting from the strong seasonal cycle of biogenic activity and from changing airmass origins. These new measurements will also differentiate between influences of algal blooms and continental dust on INPs, for which there is presently a great scarcity of data over Antarctica. Atmospheric observations include near-infrared spectroscopic measurement of cloud liquid water content and effective liquid water droplet and ice crystal particle size, cloud base height and geometrical thickness, and surface energy budget components. These observations will be supplemented by satellite remote sensing of cloud properties from the NASA Moderate Resolution Imaging Spectroradiometer (MODIS), the NASA Cloud and land Elevation Satellite (ICESat-2), and the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard the Soumi National Polar-orbiting Partnership (SNPP) and NOAA-20 satellites. This project was co-funded by the Division of Atmospheric and Geospace Sciences.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.