Secondary Marine Aerosol precursors and Links to aerosol growth at ice-melT onset in the Arctic (SMALTA)

该项目的目标是促进对大气中次生海洋气溶胶形成的认识。与初级海洋气溶胶相比，次级气溶胶解释了海洋云凝结核和云滴数浓度变化的更大比例。这项工作有望提高对海洋-大气相互作用的预测性理解，这些相互作用控制着遥远海洋上气溶胶的数量和性质，并将提高对海洋云凝结核形成的机制理解。这些结果将为改进气溶胶对海洋云特性和地球气候变化影响的模式表示提供所需的信息。挥发性有机化合物的测量将于2023年5月至6月在iboden上进行的大气河流和海冰融化开始（ARTofMELT）项目期间进行。氧合挥发性有机化合物的新测量将允许确定氧合单萜烯、线性羰基和酚类化合物是否是极地海洋地区气相海洋活性有机碳的重要贡献者。此外，对还原硫化合物的新测量将有助于确定甲硫醇是否对大西洋北极春季水华期间的自然硫收支做出了重要贡献。最后，气体-气溶胶闭合模拟将量化这些未被探索的次生海洋气溶胶前体在控制气溶胶特性方面的作用。本项目的观测和建模与北极以外的海洋区域相关，其中(1)气溶胶特性模型依赖于对次生海洋气溶胶前体的性质和特性的假设，(2)在测量和预测的氧化反应性之间达成一致的努力表明了活性有机碳的缺失来源。3名研究生参加国际合作研究。与科罗拉多州立大学自然科学教育和推广中心的合作将涉及设计动手和学生驱动的课堂活动，重点关注温室气体及其对当地农业系统、偏远海洋和极地生态系统的影响。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。

The goal of this project is to advance knowledge about the formation of secondary marine aerosol in the atmosphere. Compared to primary marine aerosol, secondary aerosol explains a larger fraction of variability in marine cloud condensation nuclei and cloud droplet number concentrations. This work is expected to improve the predictive understanding of ocean - atmosphere interactions that control aerosol number and properties over remote oceans and will improve the mechanistic understanding of the formation of marine cloud condensation nuclei. The results will provide needed information for improved model representation of aerosol impacts on marine cloud properties and Earth’s changing climate.Measurements of volatile organic compounds will be made during the Atmospheric Rivers and the Onset of Sea Ice Melt (ARTofMELT) project aboard IB Oden, in May – June 2023. New measurements of oxygenated volatile organic compounds will allow a determination of whether oxygenated monoterpenes, linear carbonyls and phenolic compounds are important contributors to gas-phase marine reactive organic carbon in a polar marine region. In addition, new measurements of reduced sulfur compounds will allow a determination about whether methanethiol makes an important contribution to the natural sulfur budget during the Atlantic Arctic spring bloom. Finally, gas-aerosol closure simulations will quantify the role of these under-explored precursors of secondary marine aerosol in controlling aerosol properties. The observations and modeling of this project have relevance to marine regions beyond the Arctic, where (1) models of aerosol properties have relied on assumptions about the nature and identity of secondary marine aerosol precursors, and (2) efforts to reach closure between measured and predicted oxidant reactivity have indicated a missing source of reactive organic carbon.Three graduate students will participate in the internationally collaborative research. A collaboration with the Natural Sciences Education and Outreach Center at Colorado State University will involve the design of hands-on and student-driven classroom activities that focus on greenhouse gases and their impacts on both local agricultural systems, and remote ocean and polar ecosystems.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.