Light absorbing aerosols (LAA) absorb sunlight and heat the atmosphere. This work presents a novel methodology to experimentally quantify the heating rate (HR) induced by LAA into an atmospheric layer. Multiwavelength aerosol absorption measurements were coupled with spectral measurements of the direct, diffuse and surface reflected radiation to obtain highly time-resolved measurements of HR apportioned in the context of LAA species (black carbon, BC; brown carbon, BrC; dust), sources (fossil fuel, FF; biomass burning, BB), and as a function of cloudiness. One year of continuous and time-resolved measurements (5 min) of HR were performed in the Po Valley. We experimentally determined (1) the seasonal behavior of HR (winter 1.83 ± 0.02 K day^–1; summer 1.04 ± 0.01 K day^–1); (2) the daily cycle of HR (asymmetric, with higher values in the morning than in the afternoon); (3) the HR in different sky conditions (from 1.75 ± 0.03 K day^–1 in clear sky to 0.43 ± 0.01 K day^–1 in complete overcast); (4) the apportionment to different sources: HR_FF (0.74 ± 0.01 K day^–1) and HR_BB (0.46 ± 0.01 K day^–1); and (4) the HR of BrC (HR_BrC: 0.15 ± 0.01 K day^–1, 12.5 ± 0.6% of the total) and that of BC (HR_BC: 1.05 ± 0.02 K day^–1; 87.5 ± 0.6% of the total).

中文翻译：

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吸光气溶胶的加热速率：时间分辨测量，云的作用和源识别

吸收光的气溶胶（LAA）吸收阳光并加热大气。这项工作提出了一种新颖的方法，以实验方式量化由LAA诱导进入大气层的加热速率（HR）。多波长气溶胶吸收测量与直接，漫反射和表面反射辐射的光谱测量相结合，以获得在LAA物种（黑碳，BC，棕碳，BrC，粉尘），来源（化石燃料，FF；生物质燃烧，BB），并且是混浊的函数。在Po Valley进行了为期一年的连续且时间分辨的HR测量（5分钟）。我们通过实验确定了（1）HR的季节性行为（冬季1.83±0.02 K天^–1；夏季1.04±0.01 K天^–1）; （2）HR的每日周期（不对称，早上的值高于下午的值）；（3）不同天空条件下的心率（从晴朗天空中的1.75±0.03 K天^–1到完全阴天的0.43±0.01 K天^–1）；（4）分配给不同来源：HR _FF（0.74±0.01 K day ^–1）和HR _BB（0.46±0.01 K day ^–1）；（4）BrC的HR（HR _BrC：0.15±0.01 K天^–1，占总数的12.5±0.6％）和BC的HR（HR _BC：1.05±0.02 K day ^–1；HR的87.5±0.6％全部的）。