Abstract. Aerosols play a critical role in the Arctic’s radiative balance, influencing solar radiation and cloud formation based on their physicochemical properties (e.g., size, abundance, and chemical composition). Limited observations in the central Arctic leave gaps in understanding aerosol dynamics year-round, affecting model predictions of climate-relevant properties. Here, we present the first annual high-time resolution observations of submicron aerosol chemical composition in the central Arctic during the Arctic Ocean 2018 (AO2018) and the 2019–2020 Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expeditions. Seasonal variations in aerosol mass concentrations and chemical composition were found to be driven by typical Arctic seasonal regimes. Organic aerosols dominated the pristine summer, while anthropogenic sulfate prevailed in autumn and spring under Arctic haze conditions. Ammonium, which impacts aerosol acidity, was consistently less abundant, relative to sulfate, in the central Arctic compared to lower latitudes of the Arctic. Cyclonic (storm) activity was found to have a significant influence on aerosol variability by enhancing both emission from local sources and transport of remote aerosol, with locally wind-generated particles contributing up to 80 % (20 %) of the cloud condensation nuclei population in autumn (spring). While the analysis presented herein provides the current central Arctic aerosol baseline, which will serve to improve climate model predictions in the region, it also underscores the importance of integrating short-timescale processes, such as seasonal wind-driven aerosol sources from blowing snow and open leads/ocean in model simulations, especially in light of the declining mid-latitude anthropogenic emissions influence and the increasing local anthropogenic emissions.

中文翻译：

---

北极中部高时间分辨率和尺寸分辨气溶胶化学成分和微观物理学的观测：对气候相关颗粒特性的影响


摘要。气溶胶在北极的辐射平衡中发挥着关键作用，根据其物理化学特性（例如大小、丰度和化学成分）影响太阳辐射和云的形成。北极中部地区的观测有限，对全年气溶胶动力学的理解存在差距，影响了气候相关特性的模型预测。在这里，我们展示了2018年北冰洋（AO2018）和2019-2020年北极气候研究多学科漂流观测站（MOSAiC）探险期间对北极中部亚微米气溶胶化学成分的首次年度高分辨率观测。研究发现气溶胶质量浓度和化学成分的季节性变化是由典型的北极季节状况驱动的。有机气溶胶在原始夏季占主导地位，而在北极薄雾条件下，人为硫酸盐在秋季和春季盛行。与北极低纬度地区相比，影响气溶胶酸度的铵在北极中部的含量始终低于硫酸盐。研究发现，气旋（风暴）活动通过增强本地来源的排放和远程气溶胶的传输，对气溶胶变异性产生重大影响，其中本地风产生的颗粒占云凝结核总数的 80% (20%)。秋季（春季）。 虽然本文提出的分析提供了当前北极中部气溶胶基线，这将有助于改善该地区的气候模型预测，但它也强调了整合短时间尺度过程的重要性，例如来自吹雪和开放的季节性风驱动气溶胶源。模型模拟中的铅/海洋，特别是考虑到中纬度地区人为排放影响的下降和当地人为排放的增加。