The seasonal variation of fine carbonaceous aerosol was evaluated in an urban traffic site in Istanbul. PM_2.5 samples were collected on selected days during four seasons between Jan 2017–Jan 2018. Daily PM_2.5 concentrations were obtained experimentally by the gravimetric method in Beşiktaş, while hourly concentrations were obtained from the Air Quality Monitoring Network of Istanbul in Çatladıkapı, Silivri, Kağıthane, and Ümraniye. Organic carbon (OC) and elemental carbon (EC) concentrations were determined by a thermo-optical carbon analyzer for samples collected in Beşiktaş. The 24-h US-EPA air quality standard of 35 μg m⁻³ was exceeded 13, 25, 41, 42, and 57% of the time in Çatladıkapı, Silivri, Kağıthane, Ümraniye, and Beşiktaş, respectively. These exceedances occurred mainly during the fall and winter owing to a combination of emissions from fuel combustion for residential heating, traffic and industry, and poor air dispersion due to weak atmospheric motion and low mixing heights. Average OC concentrations ranged as 6.62–7.32 μg m⁻³ during spring and summer, and 13.76–14.1 μg m⁻³ during fall and winter. The OC concentrations observed in this work during the summer and winter were 2–4 and 3–6 times higher than concentrations observed in the USA and Europe, respectively. The EC concentrations did not show considerable seasonal variation, with values between 2.16 and 3.26 μg m⁻³. EC concentrations in Beşiktaş were 7 and 9 times higher than concentrations observed in the USA and Europe, in order. Results obtained in this study could be helpful for future implementation of policies and strategies to reduce emissions from combustion sources in order to comply with the air quality standards.

在伊斯坦布尔的一个城市交通站点评估了碳质气溶胶的季节性变化。在2017年1月至2018年1月的四个季节中的特定日期收集了PM _2.5样品。通过重量分析法以实验方式在Beşiktaş获得了PM _2.5的每日浓度，而每小时的浓度则从位于伊利诺伊州Çatladıkapı的伊斯坦布尔空气质量监测网络获得。 Kağıthane和Ümraniye。用热光碳分析仪测定在贝西克塔斯（Beşiktaş）收集的样品中的有机碳（OC）和元素碳（EC）浓度。US-EPA的24小时空气质量标准为35μgm ^-3Çatladıkapı，Silvri，Kağıthane，Ümraniye和Beşiktaş分别被超过13、25、41、42和57％的时间。这些超标主要发生在秋季和冬季，这是由于住宅供暖，交通和工业燃料燃烧所产生的排放物的结合，以及由于空气运动较弱和混合高度低而导致的空气扩散不良。春季和夏季的平均OC浓度范围为6.62–7.32μgm ^-3，秋季和冬季的平均OC浓度范围为13.76–14.1μgm ^-3。在这项工作中，夏季和冬季观察到的OC浓度分别是美国和欧洲观察到的2-4倍和3-6倍。EC浓度没有显示出明显的季节性变化，其值在2.16和3.26μgm ^-3之间。贝西克塔斯地区的EC浓度依次比美国和欧洲的EC浓度高7到9倍。这项研究获得的结果可能有助于将来实施减少燃烧源排放的政策和策略，从而符合空气质量标准。