Abstract Absorption Angstrom Exponent (AAE) and Scattering Angstrom Exponent (SAE) values, derived from aethalometer and nephelometer measurements during a period of three years at an urban background site in Athens, are combined for the first aerosol type classification using in situ measurements in the eastern Mediterranean. In addition, single scattering albedo (SSA) and its wavelength dependence (dSSA), as well as the chemical composition of fine aerosols and precursor gases from collocated measurements, are utilized to provide further insights on the optical-chemical characterization and related sources of seven identified aerosol types. Urban aerosols are mostly characterized as Black Carbon (BC)-dominated (76.3%), representing a background atmosphere where fossil-fuel combustion is dominant throughout the year, while 14.3% of the cases correspond to the mixed Brown Carbon (BrC)-BC type, with a higher frequency in winter. The BrC type is associated with the highest scattering and absorption coefficients during winter nights, representing the impact from residential wood-burning emissions. Dust mixed with urban pollution (1.2%) and large particles mixed with BC (5.3%) have a higher frequency in spring. Furthermore, aging processes and BC coating with organic and inorganic species with weak spectral absorption (AAE

中文翻译：

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基于长期光学和在线化学表征的希腊雅典气溶胶类型原位识别

摘要 吸收埃指数 (AAE) 和散射埃指数 (SAE) 值源自雅典城市背景地点三年期间的风度计和浊度计测量值，结合使用在雅典的原位测量的第一个气溶胶类型分类。地中海东部。此外，利用单次散射反照率 (SSA) 及其波长相关性 (dSSA)，以及来自并置测量的精细气溶胶和前体气体的化学成分，可进一步深入了解七种物质的光化学表征和相关来源。确定的气溶胶类型。城市气溶胶主要以黑碳 (BC) 为主 (76.3%)，代表全年化石燃料燃烧占主导地位的背景大气，而 14. 3% 的案例对应于混合棕碳 (BrC)-BC 类型，冬季频率更高。BrC 类型与冬季夜间最高的散射和吸收系数相关，代表住宅木材燃烧排放的影响。与城市污染混合的灰尘（1.2%）和与BC混合的大颗粒（5.3%）在春季出现频率较高。此外，老化过程和具有弱光谱吸收 (AAE) 的有机和无机物种的 BC 涂层 3%) 在春季出现频率较高。此外，老化过程和具有弱光谱吸收 (AAE) 的有机和无机物种的 BC 涂层 3%) 在春季出现频率较高。此外，老化过程和具有弱光谱吸收 (AAE) 的有机和无机物种的 BC 涂层