利用 2021年 3月至 2022年 2月成都市多波段气溶胶散射系数和吸收系数等观测数据，结合 EAC-4、MERRA-2等再分析数据和 libRadtran辐射传输模型，研究了不同季节气溶胶的光学参数及总气溶胶和吸光碳质气溶胶的辐射效应。结果表明：气溶胶的光学参数具有显著的季节性差异，550 nm波长处单散射反照率（SSA）冬季最大（0. 91±0. 02），春季最小（0. 84±0. 04）；550 nm处不对称系数表现为夏季>冬季>春季>秋季；总气溶胶光学厚度（AOD）在春季与冬季较高（约 0. 77），夏季和秋季较小（0. 50~0. 53）。进一步分析吸光性碳质气溶胶的光学厚度发现，黑碳（BC）气溶胶光学厚度冬季最大，棕碳（BrC）气溶胶光学厚度在春季达到峰值。通过辐射传输模型计算结果发现，总气溶胶在地表（BOA）、大气顶部（TOA）和大气层（ATM）产生的短波辐射强迫年均值分别为-107. 21±42. 49 W·m-2、-32. 10±20. 40 W·m-2和75. 10±40. 16 W·m-2，表明气溶胶整体表现为冷却地表但加热大气的效应。黑碳的辐射强迫呈现明显的季节差异：BC 对 TOA 辐射强迫在冬季最高（7. 18±1. 59 W·m-2），秋季最低（4. 48±1. 49 W·m-2），且 BC对ATM辐射强迫的年均贡献率可达31. 3%，凸显其显著的大气增温效应，BrC辐射强迫及其在总气溶胶中的占比均表现为春季最大，冬季最小。

Using aerosol scattering and absorption coefficient observations in Chengdu city from March 2021 to February 2022，combined with EAC-4，MERRA-2 reanalysis data，and the libRadtran radiative transfer model， the aerosol optical parameters in different seasons and the radiative effects of total aerosols and absorbing carbonaceous aerosols were investigated. The results showed significant seasonal variations in aerosol optical parameters：the single scattering albedo（SSA）at 550 nm reached its maximum value in winter（0. 91±0. 02），while it was the lowest in spring（0. 84±0. 04）. The asymmetry factor（ASY）at 550 nm followed the order of summer > winter > spring > autumn. The mean total aerosol optical thickness（AOD）was higher in spring and winter （about 0. 77），but lower in summer and autumn（about 0. 50~0. 53）. Further analysis of the optical depth of light-absorbing carbonaceous aerosols revealed that black carbon（BC）contributed the most in winter，whereas the brown carbon（BrC）reached its peak in spring. The radiative transfer model calculation indicated that the annual average shortwave radiative forcing induced by total aerosols at the surface（BOA），top of the atmosphere （TOA），and within the atmosphere（ATM）was -107. 21±42. 49 W·m-2，-32. 10±20. 40 W·m-2，and 75. 10±40. 16 W·m-2，respectively. These indicated there were an overall cooling effect at the surface but a warming effect with‐ in the atmosphere for aerosol. Notably，BC exhibited distinct seasonal variations in radiative forcing：TOA forcing of BC was the highest in winter（7. 18±1. 59 W·m-2）and lowest in autumn（4. 48±1. 49 W·m-2）. Additionally，BC contributed 31. 3% of the annual mean atmospheric radiative forcing，highlighting its significant warming effect. In contrast，the radiative forcing of BrC and its proportion relative to total aerosols were higher in spring and lower in winter.